Verification of a multiple-machine program for material testing from quasi-static to high strain-rate

Nowadays characterization of the strain-rate dependence of materials becomes indispensable in crash-worthiness design of structures (i.e. car-bodies, ships) with CAE approach. To gather sufficient test data for accurate characterization, various machines are usually selected to work together on material testing covering quasi-static, intermediate and high strain-rates, which is referred to as a multiple-machine program in the present paper. Relatively rigorous verification of the multiple-machine program, including two test schemes, was designed and executed to ensure the comparability of test data from various machines. First, an acknowledged rate-insensitive aluminum alloy material was tested with a universal material test machine, an intermediate strain-rate test machine and a drop tower, respectively. Second, a rate-dependent high-strength steel material was tested with the same multiple-machine program, focusing on two strain-rate overlaps. Rate sensitivities of the tested materials were demonstrated by the test results in the two test schemes, and consistencies of the test data in the strain-rate overlaps were satisfactory, strongly verifying reliability of the multiple-machine program. Crucial measurement approaches were also decided prior to the verification, including the DIC method for deformation measurement and the dynamic force measurement to attenuate the ringing effect. (C) 2015 Elsevier Ltd. All rights reserved.