초록 close

The present study is concerned with fabrication and microstructural analysis of Cr3C2/SUS316L surface composites using high-energy electron-beam irradiation. Three kinds of powder mixtures, i.e., 50Cr3C2-50CaF2(flux), 100Cr3C2, and 87.5Cr-12.5C (wt.%), were placed on an SUS316L stainless steel substrate, which was then irradiated with electron beam. In the specimens fabricated without flux powders, the surface composite layer of 3.5~4.8 mm in thickness was successfully formed without defects by the self-fluxing effect, and contained a large amount (up to 18 vol.%) of Cr7C3 carbides in the austenite matrix. The composite layer fabricated with Cr and C powders having lower melting points than Cr3C2 powders was thicker than that fabricated with Cr3C2 powders because of more effective melting of powders during electron-beam irradiation. The hardness and wear resistance of the surface composite layer were directly influenced by hard primary Cr7C3 carbides, and thus were about two times greater than those of the untreated stainless steel substrate.