The Effects of Screen Sizes on the Surface Properties of Tepered Steel Treated by Active Screen Plasma Nitriding

Active screen plasma nitriding (ASPN) is a novel thermochemical surface treatment which has many specialities compared to the conventional direct current plasma nitriding (DCPN). The edge effect is eliminated, the hardness and layer thickness on the surface are homogeneously distributed. In this study, 42CrMo4 alloyed steel was treated with different screen sizes (screen diameter, hole size) active screen plasma nitriding. The parameters of treatment are similar in all cases (4 hours at 490°C and 2,2 torr). The nitrided samples were characterized by atomic force microscope (AFM) to analyse the roughness of the surface. The cross-section hardness of the samples and the thickness of the nitrided layers were also measured. (paper)