EFFECT OF TiB2 ADDITION ON MICROSTRUCTURE AND PROPERTIES OF THE 316L STAINLESS STEEL

In the present study, the effects of TiB2 ceramic on the density, mechanical, tribological properties and microstructure were investigated. The austenitic stainless steel/TiB2 composites with various volume of TiB2 were prepared by Spark Plasma Sintering (SPS). The samples were sintered at temperatures of 1000 degrees C and 1100 degrees C and duration of 5 minutes. The phase composition and microstructures were characterized using scanning electron microscopy. For the tested composites, the relative density, Young's modulus, microhardness, and wear resistance were measured. The highest densities were obtained for composites prepared at 1100 degrees C. The relative densities for these samples were in the range of 96-98%. Analysis of the composite microstructure revealed that TiB2 particles are homogeneously distributed in the steel matrix. In addition, formation of new fine chromium phases which were distributed along the grain boundaries was observed. The addition of hard TiB2 particles to steel leads to increase of hardness. Furthermore, the wear resistance of the composites was better for higher TiB2 contents.