Standard Practice for Compression Tests of Metallic Materials at Elevated Temperatures with Conventional or Rapid Heating Rates and Strain Rates

1.1 This practice covers procedures, equipment, and specimens for compression tests on metallic materials under conditions of (1) conventional rates of heating and straining, (2) rapid rates of heating and straining, and (3) combinations of rapid rates of heating and conventional rates of straining or of conventional rates of heating and rapid rates of straining.

1.2 This practice covers compression tests in which the specimen is heated to a constant and uniform temperature and held at that temperature while it is loaded at a controlled rate of strain. Because of their ductility, metals rarely rupture in compression tests; therefore, the end point of these tests is defined as the point at which 1.5 percent total strain under load is reached in the gage length of the specimen unless rupture occurs before that point.

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. For sheet-type compression specimens a test jig providing lateral support to the faces of the specimen is generally necessary to prevent buckling.

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

1.4 The values stated in inch-pound units are to be regarded as the standard.

1.5 This standard may involve hazardous materials, operations, and equipment. This standard does not purport to address all of the safety problems 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.