This practice covers compression test in which the specimen is heated to a constant and uniform temperature and held at temperature while an axial force is applied at a controlled rate of strain. Machines used for compression testing shall conform to the requirements prescribed. The apparatus and method for heating the specimens are not specified. The procedure for temperature control, temperature measurement, strain rate during test, and strain measurement are presented in detail. The complete compression-test system consisting of jig, strain instrument, and recorders should be qualified, in accordance with the requirements prescribed.

1.1 This practice covers compression test in which the specimen is heated to a constant and uniform temperature and held at temperature while an axial force is applied at a controlled rate of strain.

Note 1—In metals with extremely high elastic limit or low modulus of elasticity it is conceivable that 1.5 percent total strain under load could be reached before the 0.2 percent-offset yield strength is reached. In this event the 0.2 percent-offset yield strength will be the end point of the test unless rupture occurs before that point.

Note 2—For acceptable compression tests it is imperative that the specimens not buckle before the end point is reached. For this reason the equipment and procedures, as discussed in this recommended practice, must be designed to maintain uniform loading and axial alignment.

1.2 Preferred conditions of testing are recommended so that data from different sources conducting the tests will be comparable.

1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.