METHODS OF SAMPLING AXD TESTING HIGHWAY MATERIALS 121 
69. TENTATIVE METHODS OF COMPRESSION TESTING OF 
METALLIC MATERIALS 62 
iA. S. T. M. tentative standard method (5), serial designation E 9-27 Tj 
These methods deal with the form and dimensions, the machining, and the 
testing of compression test specimens of metallic materials. Such matters as 
methods of taking samples from which to prepare test specimens are treated in 
the Individual specifications for ferrous metals and for Donferroos metals. 
TEST SPECIMENS 
1. In recommending the following specimens for use in compression tests it 
is not intended to exclude entirely the use of other test specimens for special 
Wd-i 
6 
h*3d 
Jh=0.Sd 
Short 
Specimen. 
'////////////I!/////////'- 
Medium-Length 
Specimen. 
fi=/OJ 
Fig. 59. — Proporti' : compression specimens 
materials or for special forms of material. It is, however, recommended that 
wherever it is feasible the specimens here recommended he used. 
2. It is recommended that standard compression specimens be in the form of 
circular cylinders. The ends of a s}>eeimeii should be plane, as nearly as can 
be determined by the use of a straightedge and the unaided eye. In most cases 
this requirement necessitates the turning or the grinding of the ends of the 
specimen. 
3. There are recognized three classes of compression specimens for metallic 
materials, designated as short specimens, medium-length specimens, and long 
specimens, respectively. Short specimens are used for compression tests of 
such metals as bearing metals, which in service are used in the form of a thin 
plate or shell to carry load perpendicular to the surface. Medium-length 
specimens are used for determining the general compressive strength properties 
of metallic materials. Long specimens are best adapted for determining tin- 
modulus of elasticity in compression of metallic materials. In reporting the 
results of a compression test it i< important that the dimensions of th< 
specimen be given. 
"Criticisms of these tentative methods are solicited and should be directed to H. F. 
Moore, chairman of subcommittee of committee E-l on mechanical testing, University • f 
Illinois. Urbana. 111. These methods are in effect a revision of the methods for crnn- 
pression tests of the standard methods of mechanical testing of metallic materials. The 
standard methods, which were last published under the serial designation E 1-18, have 
accordingly been withdrawn. 
