WELDABILITY OF HEAT-RESISTANT AUSTENITIC STAINLESS STEEL PRODUCED BY SINTERING
Increased use and production of sintered stainless steel components require more intense investigation of their weldability. Weldability of P/M parts requires additional analysis compared to wrought or cast metals due to their specificities in physical properties. Residual porosity and sintering parameters of the heat resistant stainless steels are factors that mostly affect not only properties of sintered parts, but also their weldability. In this regard, effect of sintering parameters on the weldability of the Nb-modified heat resistant stainless steel HK 30 is discussed in this paper. Comparison of solid state and fusion welding of sintered components was performed using sinterjoining and plasma welding. Microstructure of sinter joined area, solidification structure of melting zone and microstructure changes in heat affected zone were explored using metallographic techniques. Hardness distribution through fusion zone and heat affected zone was also analysed and presented in the paper.