当前位置:首页 >> 机械/仪表 >>

BHN硬度简介


The Brinell hardness test is commonly used to determine the hardness of materials like metals and alloys. The test is achieved by applying a known load to the surface of the tested material t

hrough a hardened steel ball of known diameter. The diameter of the resulting permanent impression in the tested metal is measured and the Brinell Hardness Number is calculated as

BHN = 2 P / (π D (D - (D2 - d2)1/2)) where BHN = Brinell Hardness Number P = load on the indenting tool (kg) D = diameter of steel ball (mm)

(1)

d = measure diameter at the rim of the impression (mm)
It is desirable that the test load are limited to a impression diameter in the range of 2.5 to 4.75 mm. Approximate loads and Brinell Hardness Numbers:

Brinell Hardness Number 160 - 600 80 - 300 26 - 100

Load (kg) 3000 1500 500

Typical Brinell Hardness Numbers for Metals
Material Soft brass Mild steel Brinell Hardness Number 60 130

Annealed chissel steel White cast iron Nitrided surface

235 415 750

Steel Hardness versus Strength
Brinell Impression Diameter (mm) 2.50 2.55 2.60 2.65 2.70 2.75 2.80 2.85 2.90 2.95 3.00 3.05 3.10 3.15 3.20 3.25 3.30 Hardness HB 601 578 555 534 514 495 477 461 444 429 415 401 388 375 363 352 341 Vickers Hardness HV 640 615 591 569 547 528 508 491 474 455 440 425 410 396 383 372 360 Rockwell Hardness B 120 119 119 117 117 116 115 115 114 113 112 112 110 110 109 Hardness C 57.0 56.0 54.5 53.5 52.0 51.0 49.5 48.5 47.0 45.5 44.5 43.0 42.0 40.5 39.0 38.0 36.5 Equivalent Rm

(tonf/in2)
101 98 95 92 88 85 82 80 77 75

(kgf/mm2)
160 155 150 145 139 134 129 126 121 118

(N/mm2)
1569 1520 1471 1422 1363 1314 1265 1236 1187 1157

3.35 3.40 3.45 3.50 3.55 3.60 3.65 3.70 3.75 3.80 3.85 3.90 3.95 4.00 4.05 4.10 4.15 4.20 4.30 4.40 4.50 4.60 4.70 4.80 4.90

331 321 311 302 293 285 277 269 262 255 248 241 235 229 223 217 212 207 197 187 179 170 163 156 149

350 339 328 319 309 301 292 284 276 269 261 253 247 241 235 228 223 218 208 197 189 179 172 165 157

109 108 108 107 106 105 104 104 103 102 102 100 99 98 97 96 96 95 93 91 89 87 85 83 81

35.5 34.5 33.0 32.0 31.0 30.0 29.0 27.5 26.5 25.5 24.0 23.0 22.0 20.5 -

73 71 68 66 64 63 61 59 58 56 55 53 51 50 49 48 46 45 43 41 39 36 35 34 32

114 111 107 104 101 99 96 93 91 89 87 84 81 79 77 76 73 71 68 65 62 57 55 54 51

1118 1089 1049 1020 990 971 941 912 892 873 853 824 794 775 755 745 716 696 667 637 608 559 539 530 500

5.00 5.10 5.20 5.30 5.40 5.50 5.60 5.70 5.80

143 137 131 126 121 116 111 107 103

150 144 138 133 127 122 117 113 108

79 77 74 72 70 68 66 64 61

-

31 31 30 29 28 27 26 25 24

49 49 47 46 44 43 41 39 38

481 481 461 451 431 422 402 382 373

Force diagram

The Brinell scale characterizes the indentation hardness of materials through the scale of penetration of an indenter, loaded on a material test-piece. It is one of several definitions of hardness in materials science. Proposed by Swedish engineer Johan August Brinell in 1900, it was the first widely used and standardised hardness test in engineering and metallurgy. The large size of indentation and possible damage to test-piece limits its usefulness. The typical test uses a 10 millimetres (0.39 in) diameter steel ball as an indenter with a 3,000 kgf (29 kN; 6,600 lbf) force. For softer materials, a smaller force is used; for harder materials, a tungsten carbide ball is substituted for the steel ball. The indentation is measured and hardness calculated as:

where:

P= applied force (kgf) D= diameter of indenter (mm) d= diameter of indentation (mm)
The BHN can be converted into the ultimate tensile strength (UTS), although the relationship is dependent on the material, and therefore determined empirically. The relationship is based on Meyer's index (n) from Meyer's law. If Meyer's index is less than 2.2 then the ratio of UTS to BHN is 0.36. If Meyer's index is greater than 2.2, then the ratio increases.[1]

BHN is designated by the most commonly used test standards (ASTM E10-12[2] and ISO 6506–1:2005[3]) as HBW (H from hardness, B from brinell and W from the material of the indenter, tungsten (wolfram) carbide). In former standards HB or HBS were
used to refer to measurements made with steel indenters.

HBW is calculated in both standards using the SI units as

where:

F= applied force (N) D= diameter of indenter (mm) d= diameter of indentation (mm)

Common values[edit]
When quoting a Brinell hardness number (BHN or more commonly HB), the conditions of the test used to obtain the number must be specified. The standard format for specifying tests can be seen in the example "HBW 10/3000". "HBW" means that a tungsten carbide (from the chemical symbol for tungsten) ball indenter was used, as opposed to "HBS", which means a hardened steel ball. The "10" is the ball diameter in millimeters. The "3000" is the force in kilograms force. The hardness may also be shown as XXX HB YYD2. The XXX is the force to apply (in kgf) on a material of type YY (5 for aluminum alloys, 10 for copper alloys, 30 for steels). Thus a typical steel hardness could be written: 250 HB 30D2. It could be a maximum or a minimum. Brinell hardness numbers Material Softwood(e.g., pine) Hardness 1.6 HBS 10/100

Hardwood Lead

Pure Aluminium Copper Mild steel 18–8 (304) stainless steel 200 HB[4] annealed Glass 1550 HB Hardened tool steel 600–900 HB (HBW 10/3000) Rhenium diboride 4600 HB Note: Standard test conditions unless otherwise stated

2.6–7.0 HBS 1.6 10/100 5.0 HB (pure lead; alloyed lead typically can range from 5.0 HB to values in excess of 22.0 HB) 15 HB 35 HB 120 HB

Standards[edit]
? International (ISO) and European (CEN) Standard o EN ISO 6506-1:2005: Metallic materials – Brinell hardness test – Part 1: test method o EN ISO 6506-2:2005: Metallic materials – Brinell hardness test – Part 2: verification and calibration of testing machine o EN ISO 6506-3:2005: Metallic materials – Brinell hardness test – Part 3: calibration of reference blocks o EN ISO 6506-4:2005: Metallic materials – Brinell hardness test – Part 4: Table of hardness values US standard (ASTM International) o ASTME10-12: Standard method for Brinell hardness of metallic materials.

?

勃式硬度(BHN):测量硬质铜硬度的,就是布氏硬度〈HB〉 ,油压式操作的勃氏硬度要求最大工件高度:200mm 钢珠压子:5mm 等,最

适合用于组织不均一的铸铁材料的硬度计验 。老美要求铜材料达到120-160BHN,感觉这就是 HB(可能是音译的差别吧) ,最终根 据所加载荷(预加载荷+锤重)以及通过显微镜观察到的钢球压痕直径(一般为钢球直径的0.2-0.6倍)来判断数值大小(通常进行 3-5磁试验取值) ,最终结果可以通过下面的公式进行转化现在只有一个公式硬度換算公式: 1.肖氏硬度(HS)=勃式硬度(BHN)/10+12 2.肖式硬度(HS)=洛式硬度(HRC)+15 3.勃式硬度(BHN)= 洛克式硬度(HV) 4.洛式硬度(HRC)= 勃式硬度(BHN)/10-3


相关文章:
BHN硬度简介
BHN硬度简介_机械/仪表_工程科技_专业资料。关于BHN硬度的解释 The Brinell hardness test is commonly used to determine the hardness of materials like metals ...
硬度的基本知识与各种硬度的详细介绍
硬度的基本知识与各种硬度的详细介绍中文名称:硬度 英文名称:grade;hardness 硬度...肖氏硬度(HS)=布氏硬度(BHN)/10+12 2.肖氏硬度(HS)=洛氏硬度(HRC)+15 ...
材料硬度知识点汇总
硬度知识一、硬度简介:硬度表示材料抵抗硬物体压入其表面的能力。它是金属材料的...三、硬度換算公式 1.肖氏硬度(HS)=勃式硬度(BHN)/10+12 2.肖式硬度(HS)...
硬度对照表
硬度对照表_机械/仪表_工程科技_专业资料。硬度对照表硬度知识一、硬度简介:硬度...三、硬度換算公式 1.肖氏硬度(HS)=勃式硬度(BHN)/10+12 2.肖式硬度(HS)...
硬度分类及换算
硬度单位的转换度换算公式: 1.肖氏硬度(HS)=勃式硬度(BHN)/10+12 2.肖式...160 - 24 硬度简介及换算关系金属材料抵抗硬的物体压陷表面的能力,称为硬度。...
三种硬度对照表
三、硬度換算公式 1. 肖氏硬度(HS)=勃式硬度(BHN)/10+12 2. 肖式硬度(HS)=洛式硬度(HRC)+15 3. 勃式硬度(BHN)= 洛克式硬度(HV) 4. 洛式硬度(...
硬度对照表
硬度对照表_冶金/矿山/地质_工程科技_专业资料。硬度知识 一、硬度简介: 硬度表示...三、硬度換算公式 1.肖氏硬度(HS)=勃式硬度(BHN)/10+12 2.肖式硬度(HS...
硬度单位
硬度常有几种表示方法:肖氏硬度(又称:邵氏硬度)、洛氏硬度、布氏硬度(又称:勃氏硬度)、洛克氏硬度;其换算关系详见下列公式: 1、肖氏硬度(HS) =布氏硬度(BHN...
硬度对照表和换算方法
点击上面蓝色字体直观学机械关注我们 一、硬度简介: 硬度表示材料抵抗硬物体压入...洛式硬度(HRC)= 勃式硬度(BHN)/10-3 硬度測定範圍: HS<100 HB<500 HRC<...
HB硬度和HRC硬度对照表
硬度知识一、硬度简介: 硬度表示材料抵抗硬物体压入其表面的能力。 它是金属...三、硬度換算公式 1.肖氏硬度(HS)=勃式硬度(BHN)/10+12 2.肖式硬度(HS)...
更多相关标签:
bhn硬度 | bhn是什么硬度 | bhn硬度对照表 | 恒威注塑机料筒硬度 | 深圳挤出机用螺杆硬度 | 橡胶螺杆硬度 | 天津硬度计 | 硬度对照表 |