رويه كاري فولاد زنگ نزن مارتنزيتي با استلايت 6 و ارزيابي ريز ساختار و تاثير حضور لايه ميانيفولاد زنگ نزن آستنيتي

Hardfacing of stellite 6 on martensitic stainless steel and evaluation of microstructure and effect of austenitic stainless steel interlayer

In this paper microstructure, phase formation and Vickers hardness profile of the hardfaced layer, Co-based alloys (Stellite-6) filler metal on 410 martensitic stainless steel specimens with 309austenitic stainless steel interlayer were investigated. Gas Tungsten Arc Welding (GTAW) cladding was carried out for deposition. The specimens were investigated by an X-ray diffractometer, energy dispersion spectroscopy (EDS), scanning electron microscopy (SEM) and hardness test. According to the analyzed results, the microstructure of the clad layer consists of eutectic structure, and undissolved carbides dispersed in the matrix of the Co-based alloy with dendritic structure.The dendrites have epitaxial growth. Diffusion of carbon from the liquid Stellite to the austenitic stainless steel took place along grain boundaries resulting in the formation of chromium carbide ʹ"arms" that penetrated along the austenite grain boundaries in the interfacial region. The dilution of the clad layer by Fe from the substrate decreases hardness, wear and corrosion resistance. The interlayer resulted in a decrease in the dilution of Fe and increase in hardness.