Abrasion resistance of stainless-steel composites reinforced with hard TiB2 particles

AISI 304 stainless steel and composites reinforced with various volume fractions of TiB2 particles were fabricated by hot-isostatic pressing. Pin-on-disc measurements were used to study the two-body abrasive wear behaviour of stainless steel and the composites. In the tests, the pin specimen was sliding against the counterpart disc bonded with an abrasive SiC paper of 240 grit size. The results showed that the wear resistance of 304 stainless steel generally increases with increasing TiB2 content. This was due to the fact that the hardness of reinforcing TiB2 particles was higher than that of SiC abrasives, leading to blunting of the abrasive particles. Scanning electron microscope observations revealed the presence of long continuous grooves on the surface of the stainless steel after sliding. By contrast, hard TiB2 particles were observed to reside on the top surface of composites, thereby resisting the micro-cutting action of abrasive particles effectively.