Effect of heating mode and temperature on sintering of YAG dispersed 434L ferritic stainless steel

This study examines the effect of heating mode, sintering temperature, and varying yttria alumina garnet (YAG) addition (5 and 10 wt%) on the densification and properties of ferritic (434L) stainless steel. The straight 434L stainless steel and 434L–YAG composites were sintered in a conventional and a 2.45 GHz microwave furnace. The composites were sintered to solid-state as well as supersolidus sintering temperature at 1200 and 1400 C, respectively. Both 434L and 434L–YAG compacts coupled with microwaves and underwent rapid heating (~45 C/min). This resulted in about 85% reduction in the processing time. For all compositions microwave sintering results in greater densification. As compared to conventional sintering, microwave sintered compacts exhibit a more refined microstructure, thereby, resulting in higher bulk hardness. The mechanical properties and sliding wear resistance of 434L stainless steel is shown to be sensitive both to the sintering condition as well as YAG addition and has been correlated to the effect of heating mode on the pore morphology.