Effect of Pulse Detonation-plasma Technology Treatment on Structure of Surface Layer and Performance of T8 Steel

Abstract

T8 steel was carried out surface modification treatment by pulse detonation-plasma(PDP) technology with the capacity of 600, 800, 1000μF respectively. The microstructure and phase structure of T8 steel before and after PDP treatment were analyzed by using XRD and SEM. The microhardness and wear resistance before and after treatment were investigated by microhardness tester and wear tester. The results show that the surface smoothing occur first, and then the craters are formed. The craters are caused by the inhomogeneity of PDT energy and the material itself. PDP treatment makes the surface layer of T8 steel changed from martensite α'-Fe to austenite γ-Fe, and the Fe3N is formed due to nitriding phenomenon. The thickness of modified layer is increased with the increasing of the capacity. When the capacity is 1000μF,the average thickness of modified layer is 68.27μm and it composes of columnar and fine grain structure. The thickness of columnar structure is decreased with the decreasing of the capacity. The microhardness is improved by a factor of about 2, and the wear resistance is also obviously increased. The maximum wear resistance is 2.6 times of the matrix.

Keywords

• pulse plasma
• detonation
• T8 steel
• surface modification