Effect of Microstructural Characteristics on Corrosion Behaviour of Microwave Sintered Stainless Steel Composites

摘要

With the advantages of near net shape and tailor made materials, powder metallurgical (P/M) processing of stainless steel (SS) has become the most prominent fabrication technique, especially in automobile industry. However, the use of SS is being restricted because of its lower sintered density, which deteriorates the corrosion behavior of the final product. In the present work, an attempt has been made to enhance the corrosion response of 316L and 434L (YAG based) stainless steel composites by modifying the microstructure through microwave sintering (MWS) at 1200℃ (solid state sintering) and at 1400℃ (supersolidus liquid phase sintering). The corrosion resistance of the MWS composites was studied in 0.1 N H_2SO_4 solution. The microstructure - processing - corrosion property correlation has been determined for better understanding of MWS stainless steel composites. The dependence of electrochemical behavior of MWS composites on YAG content, interconnected porosity and processing parameters has been investigated. The results showed substantial improvement in corrosion resistance of MWS composites due to mainly full density attainment and reduced interconnected porosity.