ASTM E3547-26

1.1 This test method covers the measurement of strain rate-dependent mechanical properties of metallic materials in compression at room temperature using a Split-Hopkinson Pressure Bar (SHPB). The SHPB apparatus, also known as a Kolsky Bar, permits dynamic compression tests at strain rates typically on the order of 10² 1/s to 10⁴ 1/s.

1.2 This test method uses a one-wave analysis technique derived from the one-dimensional wave equations to calculate the dynamic compressive stress-strain behavior of solid, ductile, and homogenous metals.

1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

5.1 Significance— The data obtained in this test can include the dynamic stress-strain curve, flow stress, yield strength, fracture strain, or strain hardening at rates higher than quasi-static rates.

When data is collected across a range of strain rates for the same material, the rate dependent behaviors of the material can be characterized.

5.2 Use— Dynamic compression testing produces data that is useful in predicting the dynamic performance of materials.

Many materials exhibit strength properties that vary with changing strain rate. For metals, their strength typically increases as strain rate increases.

Compressive properties are of interest in the analyses of structures subject to dynamic compressive forces, bending moments, or both. Some applications include ballistic penetration, impact events, and ductile fracture.

These properties also inform analyses of metal working and fabrication processes that involve large compressive deformation such as forging and rolling.

For brittle or nonductile metals, compression tests offer the possibility of extending the strain range of the stress-strain data to complement tension testing data.

Although the compression test is not complicated by necking or specimen gripping as in the tension test, for certain metallic materials, buckling and barreling (see Test Methods E9, Appendix X1) can complicate results and should be minimized.