√دنیـــــــای متـــــــــــالورژی فقـــــــط از ایـــــــنجا
به "با سابقه ترين و محبوب ترين وبلاگ متالورژي در ايران" خوش آمديد

تاريخ : سه‌شنبه ٩ فروردین ۱۳۸٤


Description

The Brinell hardness test uses a ball indenter of diameter, D, which is pressed into the surface of the test piece using a prescribed force, F. The time for the initial application of the force is 2 s to 8 s, and the test force is maintained for 10 s to 15 s. The diameter of the indentation, d, is measured after the force has been removed. The Brinell hardness number, HB, is given by:

HB = Constant × F / Surface area of indentation

Standard Brinell Scales

Hardness scaleBall diameter,
D (mm)
Nominal force,
F (N)
HBW 10/30001029420
HBW 10/15001014710
HBW 10/1000109807
HBW 10/500104903
HBW 10/250102452
HBW 10/10010980.7
HBW 5/75057355
HBW 5/25052452
HBW 5/12551226
HBW 5/62.55612.9
HBW 5/255245.2
HBW 2.5/187.52.51839
HBW 2.5/62.52.5612.9
HBW 2.5/31.252.5306.5
HBW 2.5/15.6252.5153.2
HBW 2.5/6.252.561.29
HBW 1/301294.2
HBW 1/10198.07
HBW 1/5149.03
HBW 1/2.5124.52
HBW 1/119.807

The designation "HBW" specifies the use of a tungsten carbide ball indenter.
The designation "HBS" specifies the use of a hardened steel ball indenter but is now deleted from standards.

It should be noted that measurements of HBW and HBS on the same sample may differ in value due to differences in the tribological characteristics of the indenter-specimen interface.

Standards

BS EN ISO 6506-1:1999,
(BS 240:Part 1:1962)
Metallic materials. Brinell hardness test. Test method
E10-01Standard Test Method for Brinell Hardness of Metallic Materials

                                                              



ارسال توسط محسن حیدری
تاريخ : سه‌شنبه ٩ فروردین ۱۳۸٤


Vickers Hardness Tester

Description

The Vickers hardness test uses a square-based pyramid diamond indenter with an angle of 136º between the opposite faces at the vertex, which is pressed into the surface of the test piece using a prescribed force, F. The time for the initial application of the force is 2 s to 8 s, and the test force is maintained for 10 s to 15 s. After the force has been removed, the diagonal lengths of the indentation are measured and the arithmetic mean, d, is calculated. The Vickers hardness number, HV, is given by:

HV = Constant × Test force / Surface area of indentation

Standard Vickers Scales

 Micro-hardness
scales
 
 Test force
F (N)
 Low-force
hardness scales
 Test force
F (N)
  Macro-hardness
scales
 
 Test force
F (N)
HV 0.010.09807 HV 0.21.961 HV 549.03
HV 0.0150.1471 HV 0.32.942 HV 1098.07
HV 0.020.1961 HV 0.54.903 HV 20196.1
HV 0.0250.2452 HV 19.807 HV 30294.2
HV 0.050.4903 HV 219.61 HV 50490.3
HV 0.10.9807 HV 329.42 HV 100980.7

Standards

BS EN ISO 6507-1:1998,
(BS 427:Part 1:1961)
Metallic materials. Vickers hardness test. Test method
ASTM E92-82(1997)e3Standard Test Method for Vickers Hardness of Metallic Materials

                                             

ارسال توسط محسن حیدری
آخرين مطالب
کارت اعتباری ویزا

کتاب کسب درآمد از اینترنت در ۷ روز

آدرس مجازی خارجی برای گوگل ادسنس