Abstract
Repetitive-impact and impact toughness tests provide two distinct measures of a material's ability to resist impact-related wear phenomena. These tests are described in detail and results are presented for a variety of cast and forged wear-resistant alloys. In particular, past research at the U.S. Bureau of Mines using the ball-on-block and ball-on-ball repetitive-impact test is reviewed and the wear-related phenomena associated with repetitive impact are described. Impact toughness was measured using a modified dynamic tear test. To account for the heterogeneous and brittle nature of many wear-resistant alloys, a new tear test specimen was developed. Impact energies are presented for a variety of cast alloys and compared against literature values for static and dynamic fracture toughness of similar alloys. It is shown that repetitive-impact and single-blow impact tests allow a unique characterization of the material's behavior to crack initiation and propagation that dominate many wear environments.