Progress in the instrumented charpy impact test

Abstract

It has passed one century since French G. Charpy proposed the Charpy impact test in 1901. Instrumented impact test recording load history during fracture has been attempted since 1920's. It has become possible to obtain various information from this method. However, succeeding development of fracture mechanics has made it also as a qualitative screening test. To obtain quantitative fracture toughness parameters from this method, therefore, has been desired eagerly. The author developed successfully a computer aided dynamic fracture toughness evaluation system, called CAI system already in 1980's. This paper reviews development and progress in the Charpy test, especially focusing on problems of evaluation of dynamic fracture toughness by the instrumented impact test and on accuracy of measurement in the test.