he failure analysis shows that the failure form of the dies for rolling thread is pitting and delamination resulting from less toughness' The results of impact fatigue test prove that the impact fatigue life of a new type of die steel with high strength and high toughness-LM1 is longer than that of Cr12Mov steel which has undergone different heat treatment.
Abstract The paper describes the forging technology of the grinding balls of high carbon structral steel,the metallographic texture of 50 and 80mm grinding balls and the falling-ball impact fatigue test results which are analyzed and discussed at the end of the paper.
The morphology of carbides, as well as the generation and propagation of fatigue cracks in wear-resistant white cast iron after impact fatigue test were observed by means of optical microscopy and scanning electron microscopy, and the relationship between the content of RE (rare earths) in the wear-resistant white cast iron and the heating temperature as well as the length and propagation speed of the fatigue cracks were determined.
To investigate the application of impact-fatigue test for the search of brittle materials,the experimental data include the repeated times of impact-fatigue, shock ductile, hardnessand abrasion are regressed with liner relation. The result show that small energy repeatedimpact-fatigue test is appropriate for measuring the ductile of brittle materials.