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MIL-A-8625


NOT MEASUREMENT SENSITIVE I P41L-A-8625F 10 September 1993 SUPERSEDING hlIL-A-8625E 25Aprll 1988

MILITARY SPECIFICATION A?KM)ICCOATINGS FOR ALUMINUM AND ALUMINUM ALLOYS This spectf

lcation 4s approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE -

1.1 Scope. This specification covers the requirements for six types and two classes of electrolytically formed anodlc coatings on aluminum and alumlnum alloys for non-architectural applications (see 6.1). ~ 1.2 Classification. The anodic coating Types and Classes covered by this speclflcatlon are as specified herein (see 6.2 and 6.21): 1.2.1 Types Chromic acfd anodlzlng, conventional coat!ngs produced from chromic acid bath (see 3.4.1) Chromic acid anodlzlng, Iow voltage process, 22 ~2V, (see 3.4.1) Hon-chromic acid anodtzlng, for use as a non-chromate alternative for Type I and IB coatings (see 3.4.1 and 6.1.2) Sulfurlc acfd anodlztng, conventional coatings produced from sulfurfc acid bath (see 3.4.2) Thin sulfurlc acid anodlzlng, for use as a non-chromate alternative for Type I and IB coatings (see 3.4.2 and 6.1.2) Hard Anodlc Coatings (see 3.4.3)

Type 1 Type lB Type IC Type 11 Type 118 Type 111 1.2.2

Classes. -Non-dyed (see 3.5.) -Oyed (see 3.6.)

Class 1
Class 2

Beneflclal comments (recommendations, addlttons, deletlons) and any pertinent data which may be of use tn improving this document should be addressed to: (hmnandlng Officer, Naval Alr Warfare Center Aircraft Oivtslon Lakehurst, Code SR3, Lakehurst, NJ 08733-5100, by using the self-addressed Standardization Oocument Improvement Proposal (00 Form 1426) appearing at the end of this document or by letter.

AMSC NIA OIISTRIBUTION STATEMENT A:

AREA MFFP Approved for public release; distribution is unlimited.

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MIL-A-8625F 2. 2.1 APPLICABLE DOCUMENTS Government documents.

2.1.1 Specifications and standards. The following specifications and standards form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those listed in the issue of the Department of Defense Index of Specifications and Standards (DODISS) and supplement thereto, cited in the solicitation. SPECIFICATIONS MILITARY MIL-P-23377 MIL-C-81706 MIL-P-85582 FEDERAL QQ-A-250/4 STANDARDS FEDERAL FED-STD-141 FED-STD-151 MILITARY MIL-STD-105 Sampling Procedures and Tables For Inspection By Attribute Paint, Varnish, Lacquer, and Related Materials: Methods For Sampling and Testing Metals; Test Methods Aluminum Alloy 2024, Plate and Sheet Primer Coating, Epoxy-Polyamide, Chemical and Solvent Resistant Chemical Conversion Materials for Coating Aluminum and Aluminum Alloys Primer Coatings: Epoxy, Waterborne

(Unless otherwise indicated, copies of federal and military specifications and standards are available from DODSSP-Customer Service, Standardization Documents Order Desk, 700 Robbins Avenue, Building 40, Philadelphia, PA 19111-5094.) 2.2 Non-Government publications. this document to the extent specified issues of the documents which are DOD the 00DISS cited in the solicitation. of documents not listed in the DODISS the solicitation (see 6.2). The followinq documents form a part of herein. Unl~ss otherwise specified, the adopted are those listed in the issue of Unless otherwise specified, the issues are the issues of the documents cited in

AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM) ASTM B 117 ANSI/ASTM B 137 ASTM B 244 Method of Salt Spray (Fog) Testing Weight of Coating on Anodically Coated Aluminum, Measurement of Thickness of Anodic Coatings on Aluminum and of Other Nonconductive Coatings on Nonmagnetic Basis Metals with Eddy Current Instruments, Measurement of Light and Water Exposure Apparatus (Carbon-Arc Type) for Testing Paint, Varnish, Lacquer and Related Products, Standard Practice for Operating

ASTM D 822

-

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MIL-A-8625F AST14D 2244 ASTM G 23 Color Differences of Opaque Matertals, Instrumental Evaluation of Standard Practice for Operating Light Exposure Apparatus (Carbon-Arc Type) Mlth and Hlthout 14ater for Exposure of Non-metallic Mater4als Operattng Ltght-Exposure Apparatus (Xenon-Arc Type) With and 141thout Mater for Exposure of Non-metalllc matertals

ASTMG

26

-

(Application for copies should be addressed to the Amertcan Soc~ety for . Testing and Materials, 1916 Race Street, Phlladelph~a, PA 19103.) 2.3 Order of precedence. In the eventof a confl~ct between the text of this document and the references cited herein, the text of thfs document takes precedence. Nothing In thfs document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS

3.1 Materials. The materials used shall be such as to produce coatings which meet the requirements of this specification.
3.1.1 6ase metal. The base metal shall be free from surface defects, caused by machining, cutting, scratching, polishing, buffing, roughening, bending, stretching, deforming, rolling, sandblasting, vaporblasting, etching, heat treatment condition, alloy chemtstry !mbalance and inclusions, that will cause coated test panels or parts to fall anyof the requirements of this be subjected to cleaning, etching, specification. The base metal shall anodtztng and sealing procedures as necessary to yield coatings meeting all requirements of this specification.

3.2 Equipment and processes. The equipment and processes employed shall be such as to r)roduce coatinqs whfch tieet the requirements of this specification.” Unless other~ise specified tn th~ contract, purchase order or applicable drawing (see 6.2), process operating conditions shall be at the option of the supplier.
3.3 3.3.1 General. Anodizing of parts and assembles.

3.3.1.1 Anodizlnq of parts. Unless otherwtse speclfled in the contract, purchase order or amlicable drawing (see 6.2), parts shall be anodized after all heat treatment,- &ch?nlngm weld~ng, forrnlng and perforating have been completed. Unless otherwise specified in the 3.3.1.2 Anodlzinq ofassemblles. contract, purchase order or applicable dra~lng, anodic coatings shall not be applted to assembles which wI?l entrap the electrolyte In joints or recesses (components shall be anodized separately prior to assembly). When anodizing of assemblies ts authorized by the contract, purchase order or applicable drawing, the processing method used shall not result in subsequent damage to the assembly from electrolyte entrapment (Type I or 1A coatings shall be used unless another coating Type Is spec~fled). Assembles which contain non-aluminum parts such as steel, brass or organic substances, which would be attacked by pretreatment or anodiz~ng solutions or would prevent uniform formation of the anodic coating, shall not be anodized as assemblies, unless the non-aluminum surfaces are masked or electrically insulated In a manner which produces anodic coatings meeting the requirements of this specification.
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MIL-A-8625F 3.3.1.2 Anodizing of complex shapes. When anod~zlng complex shapes which will entrap the electrolyte in recesses, the processing method used shall not result in subsequent damage to the part from electrolyte entrapment (Type I or IA coatings shall be used unless another coating Type is specified). 3.3.2 Handling and cleaninq. Parts shall be so handled during all pretreatment, anodizing and post treatments that mechanical damage or contamination will be avoided. Parts shall be free of all foreign substances, oxides and soils, such as greases, oil, paint and welding flux. Parts shall have oxide and other interfering films removed by the use of proper cleaning procedures so as to be clean and have water break free surfaces. Abrasives containing iron, such as steel wool, iron oxide rouge and steel wire, which may become embedded in the metal and accelerate corrosion of aluminum and aluminum alloys, are prohibited as a means of mechanical cleaning, prior to anodizing. If special cleaning requirements are required they shall be specified in the contract or purchase order (see 6.2). 3.3.3 Reflective surfaces. When specified in the contractor purchase order (see 6.2), parts fabricated to produce a highly reflective surface shall be chemically or electrochemically brightened, prior to anodic coating (see 6.9). 3.3.4 Touch UP (mechanical damage and contact marks). Unless otherwise specified (see 6.2), mechanically damaged areas from which the anodic coating has been removed without damage to the part may be touched up using chemical conversion materials approved on QPL-81706 for Class 1A coatings and the applicable method of application. Touch up shall apply only to inadvertent marks. For Type III coatings, touch UP mechanical damage such as scratch shall only be allowed in areas which will not be subjected to abrasion (see 6.1.1). The mechanically damaged area(s) shall not exceed 5 percentof the total anodized area of the item or touch up shall not be permitted. When specified in the contract or purchase order (see 6.2), contact marks shall be touched up using the above method required for mechanical damage. 3.4 Coatings. Conventional anodic coatings as specified in the contract, purchase order or applicable drawings (see 6.2), shall be prepared by any process or operation to produce the specified coating on aluminum and aluminum alloys. 3.4.1 Type I, IB, and IC coatinqs. Type I and IB coatings shall be the result of treating aluminum and aluminum alloys electrolytically in a bath containing chromic acid to produce a uniform anodic coating on the metal surface. Type IC coatings shall be the result of treating aluminum and aluminum alloys electrolytically in a bath containing mineral or mixed mineral/organic acids (non-chromic acid) to produce a uniform anodic coating on the metal surface. Unless otherwise specified in”the contract, purchase order or applicable drawing, Type I coatings shall not be applied to aluminum alloys with a nominal copper content in excess of 5.0 percent; nominal silicon contents in excess of 7.0 percent; or when the total allowable contents of nominal alloying elements exceed 7.5 percent. Heat treatable alloys which are to receive a Type I, IB, or IC coating shall be in the required temper obtained by heat treatment, such as -T4, -T6, or T73, prior to anodizing. Type IC coatings provide a non-chromate 3.4.1.1 Type IC coatings. alternative to Type I and IB coatings. Unless approved by the procuring activity, substitution of a Type IC coating where Type I or IB is specified shall be prohibited.
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MIL-A-8625F 3.4.2 Type II and 116 coatlnqs. Type II and 116 coatings shall be the result of treating aluminum and a,lum!num alloys electrolytically in a bath containing sulfuric acid to produce a uniform-anodlc coating on-the metal surface. Heat treatable alloys shall be in the required temper obtained by heat treatment, such as -T4, -T’6,or T73, prior toanodizlng. 3.4.2.1 Type IIB coatings. Type 116 coatings provide a non-chromate alternative to Type I and 18 coatings. Unless approved by the procuring activfty, substitution of a Type 118 coating where Type I or 18 is specified shall be prohibited. shall be the result of 3.4.3 Type 111 coatlnqs. Type III coatings treating alumirtumand aluminum alloys electrolytically to produce a uniform anodic coating on the metal surface. Type III coatings shall be prepared by any process operation to produce a heavy dense coating of specffied thickness on aluminum alloys (see 3.7.2.1). Unless otherwise speclfled In the contract, shall not be applied purchase order or applicable drawing, Type 111 coatings to alumtnum alloys with a nominal copper content tn excess of 5 percent or a nomfnal silicon content In excess of 8.0 percent. Alloys with a nomfnal silicon content higher than 8.0 percent may be anodized subject to approval of the procuring activity. Heat treatable alloys shall be in a temper obtained by heat treatment, such as -T4, -T6, or T73, prlorto anodizing. 3.5 Class 1. i4henclass 1 is spectfled in the contract or purchase order, (see 6.2), the anodic coating shall not be dyed or pigmented. Any natural coloration resulting from anod~c treatment with the various alloy compositions shall not be considered coloration. The characteristic color Imparted by the sealing process shall also be considered as non-dyed. bthencl’ass2 IISspeclfled in the contract or purchase order 3.6 Class 2. (see 6.2), the anodic coating shall be uniformly dyed or pigmented by exposure to a solutlonof a suitable type dye or”staln. The color on wrought alloys shall be uniform. Cast alloys may exhfbit dye bleed-out or lackof color (or color uniformity) associated with the Inherent porosity of the casting. The dyes and ptgments used shall not be damaging to the anodfc coatings. 3.6.1 Dye color. iihendyed or plqntented coattngs are required, the color and color uniformity requirements shall be as specified on the contract, purchase order or applicable drawing {see 6.2). 3.6.1.1 Castlnq alloys. Dyed casttng alloys may shows slight lack of color uniformity. The degree of non-uniformity that 4s acceptable shall be established by the procurtng actlv~ty (see 6.2). 3.7 Detail requirements.

3.7.1

Types I,

16, IC, 11, and IIB coatings.

3.7.1.1 hiefqhtof coattnq. Pr!or to dyeing or sea14ng, Type 1, 1%, IC, 11, and IIE coatings shall meet the coating weight requirements of Table I when tested in accordance with 4.5.2 (see 6.10.6).

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MIL-A-8625F TABLE I. Types I,

IB,

IC,

11, and IIB unsealed anodic coating weights.

Coating Type

Coating Height (mg/ft2)

I

200 minimum 200 minimum - 700 maximum 1000 minimum II 200 minimum - 1000 maximum IIB j - Coating weights over 700 mg/ft2 may be used if specified. in the contract or purchase order (see 6.1.2 and 6.2).

I and IB
IC 1/

3.7.1.2 Corrosion resistance. After exposure to the salt spray test s~eclfied in 4.5.3, specimens shall be visually examined to determine that all of the following cond-itlons are met: a. Test specimens shall show no more than a total of 15 isolated pits (see 6.19), none larger than 0.031 inch in diameter, In a total of 150 square inches of test area grouped from five or more test pieces. Areas within 0.062 inch from identification markings, edges and electrode contact marks remaining after processing shall be excluded. b. Test specimens shall show no more than 5 isolated pits, none larger than 0.031 inch in diameter, in a total of 30 square inches from one or more test pieces. Areas within 0.062 inch from identification markings, edges and electrode contact marks remaining after processing shall be excluded. c. In addition to the requirements in (a) and (b) above, Type I and IB test specimens shall not exhibit patchy dark gray areas (spots, streaks, or marks). 3.7.1.3 Light fastness resistance. Class 2, dyed anodic coatings, shall show no more fading or discoloration than would be equivalent to a Delta (E) value of 3 when subjected to the light fastness resistance test (see 4.5.4), unless otherwise specified in the contract or purchase order (see 6.2). Light fastness resistance shall be determined only when specified in the contract, purchase order or applicable drawing (see 6.2). 3.7.1.4 Paint adhesion. When tested in accordance with 4.5.6, no intercoat separation shall occur between the paint system and the anodic coating or between the anodic coating and the base metal. Paint adhesion shall be determined only when specified in the contract, purchase order or applicable drawing (see 6.2). 3.7.2 Type 111 coatings.

3.7.2.1 Thickness of coating. Unless otherwise specified In the contract, purchase order, or applicable drawing (see 6.2), the nominal thickness of the coating shall be 0.002 inch (2 roils) (see 6.16, 6.17 and 6.10 through 6.10.5). Unless otherwise specified, the thickness of the coating shall not vary by more than * 20 percent for coatings up to 0.002 inches thick (2 roils)when tested in accordance with 4.5.1. Coatings over 0.002 inches (2 roils) shall not vary by more than * 0.0004 inches (0.4 roils) In thickness. A typical Type III coating thickness range Is shown in Table IV.

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NIL-A-8625F 3.7.2.1.1 14etghtof coatlnq. The coating weight may be determined tn Ileu of the coating thickness (see 3.7.2.1). at the option of the procuring activity. Unsealed Type 111 coatings shall have a mlnfmwncoatlng weight of 4320 mllltgrams per square foot for every 0.001 Inch of coating when tested in accordance with 4.5.2 (see 6.2).

3.7.2.2 Abrasion resistance. #/hen tested In accordance with 4.5.5, unsealed Type 111 coatings shall provide a hard abrasion resistant finish as specified herein (see 6.17). The anodic coating shall have a maximum wear fndex of3.5 mg/1000 cycles on aluimtnum alloys having a copper content,of 2 percentor higher (see 6.13). The wear tndex for all other alloys shall not exceed 1.5 mg/1000 cycles.

3.8.1 Types 1. IB, IC, II, and 118. All Types I, 16, IC, 11, and 115 anodtc coatings shall be completely sealed, unless otherwise specified in the contract, purchase order or applicable drawtng (see 6.2). They shall be sealed ~n accordance wtth 3.8.1.1 or 3.8.1.2 as applicable. If wetting agents are used they shall be of the non-tonic type. 3.8.1.1 Class 1. When class 1 Is specified, sealing shall be accomplished by Immersion in a sealing medium such as a 5 percent aqueous solution of sodium or potassium dtchromate (PH 5.0 to 6.0) for 15 minutes at 9f.)°Cto 100°C (194°F to 212°F), In boillng deionized water, cobalt or talckel acetate, or other suitable chemical soluttons (see 6.15). 3.8.1.2 Class 2. Nhen class 2 is specified, sealing shall be accomplished after dyeing by immersion In a sealtng medium, such as a hot aqueous solution containing 0.5 percent nickel or cobalt acetate (pH 5.5 to 5.8), boiling deionized water, duplex sealtng with hot aqueous solutloris of ntclcelacetate and sodlwn dlchromate (see 6.11), or other suitable chemical solutions. Type 111 coatings shall not be sealed where the main 3.8.2 Type 111. function ofapp?lcatlon is to obtain the maximum degree of abrasion or wear resistance. Where Type 111 coatings are used for extertor non-maintained applications requlrlng corrosion resistance but permltttng reduced abrasion resistance, the contract or purchase order shall specify that sealing is requfred. Seallng for such Type 111 coatings shall be accomplished by Imnerston tn a medium, such as bollfng delontzed water, In a hot aqueous 5 percent sodium ciichromate solutlon, ~n a hot aqueous solutfon containing or other suitable chemical solutlor?s (see 6.2). klhen n!ckel or cobalt acetate Type III coatings are provided unsealed, parts shall be thoroughly rinsed in cold, clean water and dried after artodlzing. 3.9 lllmenslons of coated articles. Articles or parts shall comply with the dlmenstonal requirements of the applicable drawings after application of the anodic coating (see 6.10.1). (For interference in close fits of parts or assemblies see 6.10.5).

3.10 Toxicity. The coatings and electrical/chemical processes used to develop these anodlc coattngs shall have no adverse effect on the healthof personnel when used for their intended purposes. Questions pertinent to this effect shall be referred by the contracting actlvfty to the appropriate departmental medical service who will act as an advisor to the contracting agency.

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MIL-A-8625F 3.11 Palntlnq/coatlnq. Painting/coating operations shall be performed as soon as practical after the anodizing process on clean coatings. If parts require storage prior to painting/coating, they shall be stored in a manner that will avoid contamination. If the parts become contaminated, they shall be cleaned in a manner that will not be detrimental to the anodic coating or the base metal (see 6.3). 3.12 Dyeing or coloring. Anodic coatings shall not be allowed to dry before dyeing or coloring. Items to be dyed or colored should be preferably coated by the Type 11 anodizing treatment (see 6.12). Dyed or.colored coatings shall not be allowed to remain in rinse waters for more than 5 minutes before sealing. 3.13 Workmanship. Except for touch up areas in accordance with 3.3.4 and as noted below, the applied anodic coating shall be continuous, smooth, adherent, uniform in appearance, free from powdery areas, loose films, breaks, scratches and other defects which will reduce the serviceability of anodized parts or assemblies. Differences in anodic coating appearance resulting from inherent base metal differences in a component such as the presence of welds, components containing cast and machined surfaces, and differences in grain size within a forging shall not be cause to reject the anodic coating unless otherwised specified in the contract or purchase order (see 6.2). Slight discoloration from dripping or rundown of the sealing solution from designed crevices in a component shall be allowed. 3.13.1 Contact marks. The size and numberof contact marks shall be at a minimum consistent with good practice (see 6.14). If a specific location for contact marks is desired, the location shall be specified on the contract or purchase order (see 6.2). 4. QUALITY ASSURANCE PROVISIONS

4.1 Responsibility for inspection. Unless otherwise specified in the contract or purchase order, the contractor is responsible for the performance of all inspection requirements (examinations and tests) as specified herein. Except as otherwise specified in the contract or purchase order, the contractor may use his own or any other facilities suitable for the performance of the inspection requirements specified herein, unless disapproved by the Government. The Government reserves the right to perform any of the inspections set forth in the specification where such inspections are deemed necessary to ensure supplies and services conform to prescribed requirements. 4.1.1 Responsibility for compliance. All items must meet all requirements of Section 3. The inspection set forth in this specification shall become a partof the contractor’s overall inspection system or quality program. The absence of any inspection requirements in the specification shall not relieve the contractorof the responsibilityof ensuring that all products or supplies submitted to the Government for acceptance comply with all requirements of the contract. Sampling inspection, as part of manufacturing operations, is an acceptable practice to ascertain conformance to requirements, however, this does not authorize submission of known defective material, either indicated or actual, nor does it commit the Government to acceptance of defective material. 4.2 Classification of inspection. herein are classified as follows: The inspection requirements specified

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141L-A-8625F a. b. 4.3 Process control Inspection (see 4.3). Quality conformance tnspectlon (see 4.4).

Process control InspectIon.

4.3.1 Process control docwnent (PCO). The anodtzer shall develop, maintain, and adhere to a PCD describing the anodizing process and procedures used to meet the requirements of thts speclflcatlon. As a minimum, the PCD shall describe the followlng:
-All steps in the processlncj sequence. -Ranges for immersion time and temperature for each step In the process. -Chemical constituents used and allowable solution control ranges to be used for solutlon analysls (see 4.3.2) for each step In the process. -Ranges for temperature, current density and anodizing time (or voltage ramps and hold times) as applied to Individual alloys or alloy series. 4.3.2 Solution analysis. Solutton analysis shall be performed on all the processing solutions in the anodizing Ilne to determine if the solution controls are within the acceptable ranges established in the PCD (see .4.3.1). Solution analysts shall be performed at least once every two weeks unless otherwise specified by the procur~ng activity. The processor shall maintain a record of the history of each processing bath, showing all chemicals or treatment solutions added to the baths and the results of all chemical analysis performed. Upon request of the procuring actlvlty, such records, as well as reports of the test results, shall be made available. These records shall be maintained for not less than one year after completion of the contract or purchase order. 4.3.3 Process control tests. To assure cont~nuous control of the process, specimens shall be tested In accordance wtth Table 11. Process control tests are conducted to determfne conformance of the anodic coatings with the requirements of this specification and are acceptable as evidence of the properties being obtalneci with the equipment and procedures employed. 4.3.3.1 Frequency of the process control tests. Process control tests shall be conducted at least once every month. In addition, the Intervals between each monthly test shall not exceed 35 days. If production In accordance with thfs speclficatton ts not performed for a period of one month or longer, process control tests shall be conducted at the start of production. TA8LE 11. Process control tests. Paragraph Specimen Preparation 4.3.3.2.1 4.3.3.2.1 4.3.3.2.2 Test Reiwirement 3.7.1.1 3.7.2.1.1 3.7.2.1

Test

Applicable Type

‘Coating

weight 3 Coating thickness 4.5.3 4.3.3.2.3 3.7.1.2 5 Corrosion ,1, 16, IC, 11, IIB (mllntmum) resistance 4.5.4 4.3.3.2.3 3.7.1.3 I, IB, IC, 11, 116 3 LIght fastness Class 2only 4.5.5 4.3.3.2.4 3.7.2.2 2 111 ,Abrasion resistance ~/ For Type 111 coatings, the coating weight may be chosen in lieu of the coating thickness at the option of the procuring activity (see 3.7.2.1.1).
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1, 16, lC, II, 111 1/ 111 ~1

Number of specimens to be tested 116 3

Method
4.5.2 4.5.2 4.5.1

9

MIL-A-8625F 4.3.3.2 Process control test specimens. Production parts shall be used for process control inspection provided they can be adapted to the app’ icable test. If the Production Darts can not be adapted to a particular test. test panels shall-b; used. At’the option of the supplier, test panels shalj be composed of either 2024-T3 per QQ-A-250/4 or the alloy representing the largest percent of work anodized during the monthly process control period. Whenever possible, the specimen panels shall be anodized with an actual production run. Additional details for the specimen panels shall be as specified in 4.3.3.2.1 through 4.3.3.2.4. Test specimens for coating weight. Coating weight shafl be 4.3.3.2.1 determined on undved and unsealed production parts or specimen panels (see 4.3.3.2). When s~ecimen panels ’are used, they shall have a minimum width of 3 inches, amlnimum length of 3 inches, and a minimum nominal thickness of 0.032 inches. 4.3.3.2.2 Test specimens for coating thickness. Coating thickness shall parts or specimen panels (see 4.3.3.2). be determinedon Type III production When specimen panels are used, they shall have a minimum width of 3 inches, a minimum length of 3 inches, and a minimum nominal thickness of 0.032 inches. 4.3.3.2.3 Test specimens for corrosion and light fastness resistance. Corrosion resistance shall be determined on dyed (Class 2 only) and sealed production parts or specimen panels (see 4.3.3.2). Light fastness testing is performed onlyon dyed (Class 2) coatings and only when specified (see 6.2). lihen specimen panels are used, they shall have a minimum width of 3 inches, a minimum length of 10 Inches, and a minimum nominal thickness of 0.032 inches. 4.3.3.2.4 Test specimens for abrasion resistance. Abrasion resistance parts or specimen panels (see shall be determined on Type III production 4.3.3.2). When specimen panels are used, they shall have a width of 4 inches, a length of 4 inches, and a minimum nominal thickness of 0.063 inches. 4.3.4 Failure. Failure to conform to any of the process control requirements specified in Table II shall result in immediate halt of production. The reason for failure shall be determined and corrected before production resumes. All traceable work from the time the failed process control specimens were anodized to the time when production was halted shall be rejected unless otherwise specified by the contracting officer. Traceable work shall be defined as all work tn which the location is know. Process control testing shall be performed at the start of production. 4.4 Quality conformance (ie. lot acceptance) inspection. Quality conformance inspection shall consist of visual (see 4.4.2.1) and dimensional (see 4.4.2.2) examinations (see 6.2.1). When specified in the contract or purchase order (see 6.2), quality conformance inspection shall also include paint adhesion testing in accordance with 4.5.6. 4.4.1 @J. A lot shall consist of all items of the same part number anodized in the same tank using the same process and of the same coating type In addition, the lot size shall and class offered for acceptance at one time. not exceed the number of items processed in one shift.

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MI1--A-8625F 4.4.2 Samplfnq for visual and dimensional examinations. Samples for visual and dimensional examinations (see 4.4.2.1 and 4.4.2.2) shall be selected from each lot of anodtzed parts \n accordance with the provisions of The acceptance criteria shall be as !iIL-STD-105, InspectIon Level II. specified In the contract or ~urchase order {see 6.2 and 6.20). If no acceptance cr~teria Is specified, the criteria given in 6.20 shall be used. 4.4.2.1 Visual examination. Samples selected In accordance with 4.4.2 shall be inspected and visually examined for compliance with 3.13 after anodizing, sealing and dyeing (if applicable). 4.4.2.2 Dimensional examination. Samples, selected In accordance with 4.4.2, shall be dimensionally Inspected for compliance with 3.9, unless otherwise specified by the procurtng activity (see 6.10.5). 4.4.3 Samplinq for paint adhesion testlnq. When the patnt adhesion test is soeclfied (see 4.4), two test panels shall be tested in accordance with 4.5.6 todetermlne conformance to-3.7.1.4. The test panels shall be 3 inches in width by 10 tnches in length with a minimum nominal thickness of 0.032 inches. Unless otherwise specified, the test panels shall be composed of either 2024-T3 per QQ-A-250/4 or the predominant alloy in the lot from which the paint adhesion test is requtred to be performed. Unless another paint system is specified (see 6.2), the paint system in 4.4.3.1 shall be applied to the anodized panels. 4.4.3.1 Preparation of paint adhesion specimens. Specimen panels (see 4.4.3) shall be finished with one coat of an epoxy-polyamide primer conforming to either MIL-P-23377 (Class 1 or 2) or 141L-P-85582_. In either case the primer shall be applied toa dry film thickness of 0.0006 to 0.0009 inch (0.6 too.9mll) and dried In accordance wfth the applicable primer specification before testing in accordance with 4.5.6. 4.4.4 Failure. Failure to conform to any of the quality conformance requirements shall result in rejection of the represented lot. 4.5 Test methods.

4.5.1 Anodic coatinq thtckness. Test specimens prepared in accordance with 4.3.3.2.2, shall be tested for anodfc coating thickness in accordance wtth ASTM B 244, Method 520 or Method 520.1 of FEO-STO-151 to determine conformance to the requirements of 3.7.2.1. If etther Mm B 244 or Method 520 of FEO-STO-151 Is used, the thickness shall be computed as the average of thickness h case of dispute, anodlc coating not less than e~ght measurements. shall be determined by measurement of a perpendicular cross section of the anodized specimen using a metallographlc microscope with a calibrated eyepiece. 4.5.2 Anodlc coating weight. Test specimens prepared in accordance with 4.3.3.2.1 shall be tested for anodtc coating weight either in accordance with ANS1/ASTblB 137, or the method speclfled In 4.5.2.1. Type 1, 16, IC, 11, and IIB coatings shall be tested for conformance with the requirements of 3’.7.1 .1’. If the procuring activity chooses to have coating weight tested in lieu of the coating thickness for Type III hard anodized coatings, it shall be tested for conformance with 3.7.2.1.1.

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MIL-A-8625F 4.5.2.1 Method. Anodlc coating weight determinations shall be accomplished in the following manner: a. Test specimens shall be weighed immediately after anodizing, prior to dyeing or sealing. An analytical balance or other instrument sensltlve to at least 10 percent of the net Anodic coating weight on test specimen shall be used. Specimens shall be cleaned and dried for a minimum of 30 minutes at 93°~ 6*C (200°~ 10”F) and allowed to cool to room temperature before weighing. Immediately after weighing, the test specimens shall be stripped by immersion in a phosphoric-chromic acid solution for a minimumof 5 minutes, (not to exceed 6“minutes), at 100°~60C (212°Z 10”F). The solution shall consist of the following: Phosphoric acid, 85 percent Chromic acid (Cr03) Water to make 35 milliliters 20 grams 1,000 milliliters

b.

c. The test specimens shall be removed from the solution, washed in distilled water, dried, and weighed. The 5-minute exposure shall be repeated until the coating is completely removed, which is Indicated by the specimen’s weight remaining constant. The stripping solution shall be discarded after l-literof the solution has dissolved 5 grams of the anodic coating.
d. After final weighing, the total surface area of the test specimen shall be accurately determined.

e. The unit film weight shall be determined by subtracting the weight in milligrams of the stripped specimen from its weight in milligrams prior to stripping and dividing by the surface area expressed in square feet.
4.5.3 Corrosion resistance.

4.5.3.1 Method. Test specimens, prepared in accordance with 4.3.3.2.3, shall be washed in distilled or deionized water, dried with a soft cloth and then subjected to a 5 percent salt spray test in accordance with ASTMB 117, except that the significant surface shall be inclined 6 degrees from the vertical. Specimens shall be exposed for 336 hours. After exposure, specimens shall be examined to determine compliance with 3.7.1.2. 4.5.4 Light fastness resistance (Class 2 only). Test specimens, prepared in accordance with 4.3.3.2.3, shall be tested for light fastness resistance by exposure to ultraviolet radiation in accordance with either ASTM G 23, ASTM D 8220r ASTM G 26, for a period of 200 hours, except that the specimens will be exposed continuously to llght without water spray. After exposure, specimens shall be compared with duplicate specimens not exposed to a light source for the same period of time to determine the Delta (E) value in accordance with ASTM D 2244. The Delta (E) value shall be used to determine conformance with 3.7.1.3.

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12

MIL-A-8625F 4.5.5 Abrasion resistance. Test specimens, prepared In accordance with 4.3.3.2.4, shall be tested in accordance wfth Method 6192.1 of FED-STD-141 using CS-17 wheels wfth a 1000 gram load. The wheels shall revolve on the anodic coating at a speed of 70 revolutions per minute (RPM) for 10,000 cycles. The abrasion wheels shall be refaced at least once every 10,000 cycles. The wear tndex shall be determined after the 10,000 cycle period by dividing thewetght loss by 10. The wear index shall meet the requirements of 3.7.2.2. 4.5.6 Paint adhesion test. When specified (see 4.4), specimen panels prepared in accordance with 4.4.3 shall be tested for wet tape adhesion. The test shall be conducted as described in method 6301 of FED-STD-141 to determine conformance with paragraph 3.7.1.4. 5. PACKAGING (Not applicable to this specification)

6. NOTES (This section conta!ns Information of a general or explanatory nature that may be helpful but ts not mandatory) 6.1 Intended use. The coatings covered in this document are intended to ytpvide corrosion resistance, improved paint adhesion and abrasion resistance as specified in 6.1.1 through 6.1.3. This document is not intended to sufficiently cover anodic coatings for use tn structural adhesive bonding. 6.1.1 Types 1, IBand 11. The conventional Types 1, IB and II anodic coatings are intended to improve surface corrosion protection under severe service conditions or as a base for paint systems. Anodic coatings can be colored with a large variety of dyes and pigments. Types 1, Illand 11 coatings provide better corrosion protection at higher cost than the chemical conversion systems. Repair of mechanically damaged areas by the use of materials conforming to MIL-C-81706 (see 3.3.4) wI1l not restore abrasion resistance but will provide an effective means of reestablishing corrosion resistance. bihere anodic coatings are required on fatigue critical components, Type I and 18 coatings (see 6.1.2) are used due to the thinness of the coating (see 6.10.7). 6.1.2 Type ICand IIB. Type IC and IIB coatings provide non-chromate alternatives to Type I and 18 coatings where corrosion resistance, paint adhesion, and fatigue resistance is required. Please note that Type ICor 116 may not serve as suitable replacements when the effects of electrolyte entrapment IISthe prfmary concern (see 3.3.1.2 and 3.3.1.3). Maximum Type IC and Type IIB coating weights of 700 mg/ft2 and 1000 mg/ft2, respectively, are specified in Table I for fatigue purposes (see 6.10.7). If higher Type IC coating weights are permissible for the Intended use, It should be specified in the contractor purchase order (see 6.2). If higher Type lIB coating weights are permissible for the tntended use, Type 11 should be specified. Type 111 coatings are Intended to provide wear and 6.1.3 Type 111. abrasion resistant surfaces with Improved corrosion protection due to greater thickness and weight than the conventional anodic coatings. Sealing of Type 111 coatings is not recommended unless corroston resistance ts also a factor. Wear resistance is reduced by seallng. Anodic coatings form an excellent base for most types of paint systems, adhesives and dry film lubricants. Hard strength. These factors should be considered in coatings may reduce fatigue proposed use of parts subjected to cycl~c loads. Generally, these hard coatings should not be used on parts or portions of parts which normally during rework would require restoring of dimensional tolerances because of wear of hard coated surfaces.
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13

MIL-A-8625F 6.1.3.1 Applications. Type 111 coatings are used In such applications as valves, sliding parts, hinge mechanisms, cams, gears, swivel joints, pistons, rocket nozzlesj insulation plates, blast shields, etc. 6.2 Acquisition requirements. following: a. b. c. d. e. f. 9. h. i. j. k. Acquisition documents should specify the

Title, number and date of this specification. Type of anodic coating (see 1.2.11. Class of anodic coatinq (see 1.2.21. S~ecial Drocess oDerat~nq conditions, if amlicable”( see 3:2). Special cleaning and fab~ication requirements (see 3.3.1, 3.3.2, and 3.3.3). If coating weight for Type IC can exceed the maximum specified in Table I. Color and uniformity of Class 2 coatings, if applicable (see 3.6.1 and 3.12}. Degree of non-uniformity of dyed casting alloys (see 3.6.1.1). Light fastness resistance, if applicable, and a Delta E value if different than 3 (see 3.7.1.3). Type 111 coating thickness, inapplicable (see 3.7.2.1). if substituted Coating weight for thickness, Type III,

(see 1.
m.

3.7.2.1.1).

n. o. P.

Special sealing requirements (see 3.8). When applicable, the allowable difference in anodic coating appearance resulting from inherent base metal differences (see 3.13). Provide the specific location of contact marks if important to the function of the part (see 3.13.1 and 6.14). Acceptance criteria for quality conformance inspections (see 4.4.2 and 6.20). If paint adhesion testing is required for quality conformance testing (see 4.4) and the required paint system (if different than that in 4.4.3.1).

6.2.1 Consideration of data requirements. The following data requirements should be considered when this specification is applied on a contract. The applicable Data Item Description (DID) should be reviewed in conjunction with the specific acquisition to ensure that only essential data are requested/provided and that the DID is tailored to reflect the requirements of the specific acquisition. To ensure correct contractual application of the data requirements, a Contract Data Requirements List (DD Form 1423) must be prepared to obtain the data, except where DOD FAR Supplement 27-4.75-1 exempts the requirement for a CIDForm 1423. Suggested Tailoring 10.2.7.1

Reference Para. 4.4

DID Number DI-NDTI-80809A

DID Title TEST/INSPECTION REPORTS

The above DID was cleared as of the date of this specification. The current issue of DOD 501O.12-L, Acquisition Management Systems and Data Requirements Control List (AMSDL), must be researched to ensure that only current, cleared DID’s are cited on the DD Form 1423.

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14

MIL-A-8625F 6.2.2 Exce~tlons to dra~lnqs for types 1, 18, IC, 11. and IIB coatings. I+/henhe anodlc coating type !s not speclfled on the drawing, Type 1, 113,IC, t 11, or IIB may be furnished wttl’tln the lfrnltsof this speclflcation, at the option of the contractor. When the coating class Is not speclfled on the drawing, either Class 1 or Class 2 may be supplied within the llmftsof this specification, at the option of the contractor. 6.3 Patntlnq/coating. When anodtc coatings are required to be palntedlcoated, the parts should be drted and painted as promptly as possible, durtng which time, exposure to contam~natlon should be kept to amlnlmqm. Prtor to painting or coat~ng anodized parts, wiping, buffing or mechanical operations should be kept to a mlnlmum. Thts may damage the less dense outside layer of the anodlc coating making It susceptible to subsequent Sea?lng processes can have a significant effect on adhesion failures. adhesion of prfmers and other polymertc materials to the anodized surface as well as the cohestve strength of the anodized layer. If these factors are fmportant to the application, such as subsequent painting operations, specific details for (or the omlsslon of) the sealing process should be specified in the contract or purchase order. 6.4 Electrolytic actfon. Severe attack by the electrolyteon castings or welds may be occasioned either by unsound castings, Improper welding practice, a difference In composition between the weld and the base metal or, particularly tn the case of the sulfurlc acid process, the retentionof the solution in cracks, crevices, or Irregular surfaces. Severe attack by the electrolyte may also be caused by contaminants in the electrolyte, particularly chlorides or by Improper racking of the parts. 6.5 Anodlzinq rate. Alumlr?um and alwnlnum alloys may be conveniently grouped by anodizing rate, especially In the case of the chromic acid process (Type 1) for conventional coatings. However, either the chromic (Type I) or the sulfuric acid process (Type 11) will anod!ze mtxed loads satisfactorily, depending upon local processing preference. Suppllers are cautioned that. especially In the sulfuric acid process. the anodizing time wIII have to be sufficiently long to assure that the slower anod~zlng alloys have at least a mlnlmum coating thickness. In some cases, thts may result In improper coatings on the fast anodlzlng alloys. 6.6 Color match. FE&ST1l-595 may be used as a guide for specifying color of anodic coatings. The color standards In FED-STD-595 are ~ntended for paint finishes and should be used for approximate comparison only with the anodic coatings (see 6.2). 6.7 Lappln~. The Type 111 anodlc coat~ngs generally have Increased surface roughness as well as having the property of betng less dense on the top surface than tn the core of the coating toward the base metal. Such coattngs may be processed overstzed and then lapped or honed down to the final desired dimension. 6.8 Coating baths. for ~nformation, It should be noted that processes provldtng other coating electrolytes for the conventional coatings may be aqueous solut$ons containing oxallc acid, boric acid plus annnonium borate and nitrides. There are proprietary processes requiring coating electrolytes, other than sulfuric acid, for the Type 111 coatings; for example, the various

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15

MIL-A-8625F Alumilltes, the Martin Hard Coat, the Sanford, the Hardas and others. One of the Alumillte processes requires an aqueous solution containing both sulfuric and oxalic acids for the bath. Other baths used less frequently and for special purposes employ sulfosallcylic, sulfamic or sulfophthalic acid solutions. 6.9 Chemical brightening and Polishlnq. Chemical brightening can be beneficial by improving the appearanceand corrosion resistance, in smoothing the metallic surface by removing certain contaminants and in enhancing the continuity of the anodic coatings on aluminum alloys (see 3.3.3.). The percentage of reflectivity obtained from apart which has been electrolytically brightened and subsequently anodized will depend on the alloy and the coating thickness. Certain alloys are more capable of obtaining a highly brightened surface and thicker anodic coatings will reduce reflectivity. 6.10 Design information.

6.?0.1 Surface dimension of parts. On specifying the thickness of coatings, especially for the Type III coatings, allowance must be made for dimensional increase. Both a machining dimension and a coated dimension should be placed on applicable drawings. An increase in dimension, equal to one half of the thickness of the applied coating, can be expected for each surface coated due to surface growth. For example, for a 0.004 inch (4 roils) coating on close tolerance parts, a pre-machining allowance of 0.002 inch (2 rnils) per surface must be made prior to hard coating. If close fits are specified in design drawings, buildup In thickness caused by anodic coatings, especially Type 111, may result in interferenceon assembly. 6.10.1.1 Holes. In the case of small holes and tapped holes, coating thickness can vary from no film to a full normal coating. Holes, both tapped and not tapped, over 1/4 inch should be anodized. Parts with Type II coatings, external or internal, with a total tolerance of 0.0004 inch or less, if lapped, honed or stoned to size after anodizing, should be subsequently treated with QPL-81706 materials to provide surface protection. Discoloration on the surface that has been sized is acceptable (see 6.6). The designer is cautioned to require adequate thread and hole sealing operations in subsequent assemblies as may be required to produce the necessary corrosion resistance. 6.10.2 Thread dimensions. All anodic coatings will affect thread dimensions for external and internal threads; the major and minor diameter will be increased 2 times the amount of growth (see 6.10.1). The pitch diameter for threads having an included angle of 60° will increase 4 times the amount of growth. For threads having an included angle, other than 60°, the pitch diameter will increase 2 times the amount of growth (see 6.10.1) divided by the sine of 1/2 the included angle. 6.10.3 Fabrication. Successful use ofanodic coatings, especially the hard Type 111, depends on proper product design. Because of the manner of formation, anodic coatings will develop voids at sharp corners and edges. Sharp edges and corners are difficult to anodize satisfactorily and in general should be avoided. All edges and inside corners should be radiused prior to anodizing. Chamfering should not be used unless resulting sharp edges are radiused. In general, to avoid any uncoated edges or inside corners, the piercing and blanking operations should comply with the radii of curvature for nominal coating thicknesses as in Table III.

16
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MIL-A-8625F TA9LE 111. Radtl of curvature for nominal coattnq thfckness.

Mominal coatinq
0.001 0.002

0.003

thickness, inch ~ Radius of curvature (edge and Inside corner) approximately 1/32 inch approximately 1/16 Inch approximately 3/32 Inch

0.004

approximately

1/8 Inch

6.10.4 Coatlnq thickness. Thtckness of the heavy Type 111 coattng can be controlled to extremely close tolerances. Anodized coattng can, be obtained with tolerances of as llttle as ~0.0001 inch (0.1 roll). 14ith all anodizing processes used primarily for engineering rather than for decorative purposes, a number of highly specialized techniques are used for operation control. One method that may be employed Is to carefully measure the coated part whtle still wet and replace It in the bath for a fixed pertod of treatment. Calculations based upon a calculated rate of coating per unitof processing time may be used as the bas4s for determining the exact duration of processing required for the specific alloy betng coated.
6.10.5 Coatinq dimensions. Table IV gives typical thickness ranges of anodic coatings that can be applted on aluminum and aluminum alloys. All material. If Interference is anodic coatings are harder than the substrate required for assembly, and Is accomplished by force fitting, Type 1, IB, IC, IIB, and some Type 11 coatings are too thin and too brittle to withstand 14ithType 111 coatings assembly may be abrasive damage during such assembly. accomplished by grinding, lapping or otherwise removfng the surplus coating. All artodic coatings are brittle and may crack and span due to force fittings. TABLE IV. Thickness ranges of anodlc coatinqs on aluminum and aluminum allovs. Coating Type I, 18, IC, and IIB Th~ckness ranqe, inch

I
1

11 111

1

0.00002 too.0007 0.00007 too.oolo 0.0005 to 0.0045

I

6.10.6 Coat$ng thickness. Table V g~ves typical mlnlmum thicknesses ~n Inches of anodic coatings formed on some wrought and cast alloys that could comply wtth the minimum coatfng weight requirements in accordance wtth Table I for Types I, IAand II, Class 1.
TA8LE V. Mlnlmum thickness (typical) tn Inch of anodlc coatlnqs. Thickness of ~ oatlng, inch Type II Type 1, 18, and IC 0.000093 0.000029 0.000125

Alloy designation

11(IO
2024-T4 2024-T6

3003 5052 5056 6061 -T6
7075-T6 Alclad 2014-T6 Alclad 7075-T6 295-T6 356-T6 514

0. oiioo44 0.000035 0.000033 0.000021 0.000034 0.000040 0.000045 0.000041

0.000103 0.000098 0.00;099

0.000107 0.000102 0.000086

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MIL-A-8625F The fatigue properties of aluminum alloys can be reduction varies with the severely reduced by anodic coatings. The amountof process. As a general rule, the thicker the coating the greater the reduction In fatigue will be. 6.11 Duplex sealing. The corrosion resistance of dyed parts, especially those anodized in a sulfurlc acid bath, Type II and IIB, may be enhanced by treatment In a sodium bichromate solution either during or after conventional sealing with nickel acetate. This treatment can cause slight changes in the color of the dye. Paint systems adhere very satisfactorily to.duplex -sealed dyed coatings. However, where any objection with such duplex sealing application is warranted because of a firmly desired coloration, the dual process for sealing should not be used. 6.12 Dyeing or coloring Type I, IB, IC, and IIB coatings. Type 1, IB, and IC coatings have a different pore structure and along with Type IIB coatings are thinner than Type II coatings which makes them more difficult to dye. As a result, Type I, IB, IC, and IIB black anodized may not readily obtainable. 6.10.7 Effect on fatique.

6.13 Alloys havinq 2 percent or more copper content. Aluminum alloys having a nominal copper content of 2 percent or higher include all 2XXX series alloys, 7050 and 7178 (see 3.7.2.2).
6.14 Size of contact marks. In order to obtain the desired current density without burning the parts, the size or number of contact marks will be greater on parts having higher surface areas. Because current density is a measure of the required current per square foot of aluminum being anodized, a part having twice as much surface area relative to another will require twice as much current. Trying to force the higher currents required for larger parts through smaller contact areas sufficient for parts with lower surface areas may result in burning. 6.15 Sealing. The hot deionized water seal is advantages from an environmental viewpoint. In addition, The useof a hot deionized water seal on Type I and IB coatings yields good corrosion resistance and may eliminate the appearance of patchy dark gray areas after salt spray exposure (see 6.18 and 3.7.1.2). 6.16 Effects on coating thickness. A hardcoat of 2 roilsor more is extremely difficult to obtain on high silicone die castings such as 360, 380, and 383.- It is recommended that this be considered when specifying a coating thickness for high silicone castings. thickness on abrasion resistance. The 6.17 Effects of Type III coating abrasion resistance of Tme III coatinqs will decrease as the coating thickness approaches 3 roils. In g~neral, the ab~asion resistance does not inc;ease with increasing coating thickness. 6.18 Corrosion resistance of Type I and IB coatinqs. Although pitting may not be visually evident with the unaided eve. the amearance of dark way areas on the s~rface after salt spray expo~ure is an-indication of co~ti~g degradation. 6.19 Definition of a pit. A pit s defined as an area of localized corrosion having a depth greater than its width. As a general rule, a pit usually displays a characteristic tai’ or line (see 3.7.1.2).

18
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MIL-A-8625F 6.20 Acceptance cr~teria. Prev\ous revlslons of thts document spectfied an Acceptable Quallty Level (AQL) of 1.5 percent defective.

6.21 Supersedure data. Type I, conventional chromic acid anodizing, referenced throughout this spec~fication is the same as the Type 1A tieslgnated in the D revlslon and the Type I in all versions preceding the D revision. 6.22 Changes from previous issue. Asterisks are not used tn this revision to Identify changes with respect to the previous Issue due to the extensiveness of the changes.

6.23

Subject term (keyword) llstinq.
Alumlnum Aluminum alloys Anodlc coatings Anodlzlng Chromates Chromic Acid Potassium Bichromate Sodium Bichromate

Custodian: Army - hill tiavy AS Alr Force - 11 Review activities: Army - Al?,AV, W Havy - OS, SH Alr Force - 70, 71, 80, 82, 85, 99 User actlvltles: Army - AT, CR, ME

Preparing activity: Navy - AS (Project no. MFFP-0493)

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S?’ANDARDEATION DOCUMENT IMPROVEMENTPROPOSAL
ftIJSTfUJCf10F4S
1. 2.

The preparing activity must complete letter should given. be Thesubmitter
a~”vity

Mocks 1,2,3,

and 8. [nblock1,both the document
and 7.

number and revision

of this form must complete

blocks 4,5,6,

3. The preparing

must provide a reply within

30 days from receipt of the form. of to

NOTE: Thisform may no? be used to request copies of documents, nor to request waivers, d~ clarification requirements on current contracts. Comments submitted on this form do not constitute or jmply authorization waive any portion of the referenced document(s) or to amend contractual requirements.

.
1. tdATu RE OF CHANGE

(kfenti& gw4grJph

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include proposed rewrite, if po.uible. Amch exlra SfQMS needed.J as
. . . . ..

. REASON FOR RECOMMENDATION

PMPARING ACTIVITY b. TELEPHONE(include&w Cafe) NAMECO!WU!AND1 NG OFFICER, NAVAL AIR (2) AUTOVON WARFARE CENTER AIRCRAFT DIV IS ION LAKEHURST ‘1) Commerda’ SYSTEMS REQUIREMENTS DEl?ARl?vIENT [908 ) 323-7488 624-7488 /@DM5~ (IncludeZip CodeJ lF YOU DO NOT RECEIVE A JWI,Y WITHIN 4S DAYS. CONTAa: CODE SR3 Defense Quality md Standwdixation Otiice S203 Leesbutg Pike, Suite 1403, F~lls church, VA 2204t-3466 LAKEHURST, NJ 08733-5100 Source: http://www.assistdocs.com -- Downloaded: 2006-08-13T14:28Z Check the source to verify that this Telephone (703) 7S&2340 is the current version before AU’TOVON 289-2340 use. I




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空军 准备单位:海军 采用单位:陆军 军用规格说明 铝和铝合金的阳极氧化涂层 1993 年 9 月 10 修改的内容已形成文件 MIL-A-8625F,并且以得到所有防卫部门的所有...
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经严格标准测试符合下列规范: 经严格标准测试符合下列规范: BS5599 英国国家标准; 英国国家标准; AMS2469C 太空材料规格; 太空材料规格; MIL-A-8625E TYPE THREE...
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2页 免费 中文美国军标MIL-A-8625[1... 13页 10财富值如要投诉违规内容,请到百度文库投诉中心;如要提出功能问题或意见建议,请点击此处进行反馈。 ...
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