Effect of boron on sintering of a ferritic stainless steel

This work studies the effect of boron on the density of a 409Nb ferritic stainless steel obtained by powder metallurg during the process of sintering. The purpose of adding boron is to promote the formation of a liquid phase during sintering at temperatures below 1200 deg C. The boron contents varied from 0.0 to 1.5%wt. Specimens were compacted at 700MPa, and sintering was made at 1075 and 1150 deg C during 60 minutes under a hydrogen atmosphere, using a heating rate of 20 deg C/min. Density values were determined by the Archimedes method, and the samples were analyzed using scanning electron microscopy. This work shows the dependence of the steel density and morphology of the microestructure as a function of boron content and the temperature of sintering.