Fundamentals of Materials Science and Engineering: An Integrated Approach, 3e

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GTBL042-07 GTBL042-Callister-v2 August 6, 2007 12:43


224 • Chapter 7 / Mechanical Properties

Table 7.5

Hardness-Testing Techniques

Shape of Indentation

Formula for

Test

Indenter

Side View

Top View

Load

Hardness Number

a

Brinell

10-mm sphere

of steel ortungsten carbide

D d

d

P

HB

=

2 P

π
D

[D



D

2 −

(^2) d
]
Vickers
microindentation
Diamond
pyramid
136
°
d^1
d^1
P
HV




  1. 854
    P/
    d
    21
    Knoop
    microindentation
    Diamond
    pyramid
    l/b
    = 7.11
    b/
    t = 4.00
    t
    b
    l
    P
    HK


    14.2
    P/l
    2
    Rockwell and
    SuperficialRockwell
    Diamond cone;
    (^116)
    ,
    1 , 8
    1 , 4
    1 , in. 2
    diametersteel spheres
    120
    °
    60 kg100 kg150 kg
    ⎫⎪⎬ ⎪⎭
    Rockwell
    15 kg30 kg45 kg
    ⎫⎪⎬ ⎪⎭
    Superficial Rockwell
    ⎧⎪⎪⎨ ⎪⎪⎩
    a
    For the hardness formulas given,
    P
    (the applied load) is in kg, while
    D, d, d
    , and 1
    lare all in mm.
    Source:
    Adapted from H. W. Hayden, W. G. Moffatt, and J. Wulff,
    The Structure and Properties of Materials,
    Vol. III,
    Mechanical Behavior




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1965 by John Wiley & Sons, New York. Reprinted by permission of John Wiley & Sons, Inc.
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