Comparison of dynamic test proposals. Some UK experience on testing at intermediate rates. Remarks on the interpretation of instrumented Charpy-type impact tests

In a first part, the author compares some elements appearing in other contributions of this conference, particularly those describing dynamic test procedures. This brief comparison is made in terms of objectives, velocity, machines, test pieces, striker, instrumentation, and interpretation (either elastic or elasto-plastic-fully plastic). In a second part he comments proposals based on British test programmes to define standard test procedures at intermediate rate. In the last part, he shows that sufficient understanding of the instrumented pre-cracked Charpy test exists from both simple qualitative studies that reveal the important parameters and from recent optical and computational studies which include the effects of plasticity to believe a meaningful value of fracture toughness can be extracted from the test. He admits the important role of the different test parameters, and the fact that some tests might be less precise than static tests