Improvement in wear resistance of TiNi-based composites by hot isostatic pressing

It has been recognized that matrixes of many tribo-composites are not strong enough and rapid wear of the matrixes significantly decreases the integrated wear resistance of the composites. However, it is not always effective to use a harder matrix, since such a matrix may not act effectively as a binder to retain the reinforcing particles or may lack toughness. The TiNi alloy exhibits excellent wear resistance and flexibility due to its pseudoelasticity, which may render this alloy an ideal matrix material for tribo-composites. Recent work demonstrates that TiNi-matrix composites do possess high wear resistance and that their resistance can be further enhanced if the porosity in the composites can be decreased. Attempts were made to improve the composites using hot isostatic pressing (HIP). This paper reports our studies on the effects of the HIP treatment on the reduction of pores in the TiC/TiNi and TiN/TiNi composites and the resultant changes in their properties including the wear resistance.