Effect of Reinforcement Size and Distribution on Tensile and Wear Properties of Titanium Matrix Composites by Horizontal-type Centrifugal Casting

摘要

Different sizes (1500 and 150μm) and contents (0. 94,1. 88 and 3. 76wt%) of B4C were added to the titanium matrix during vacuum induction melting which can yield the in-situ reaction of 5Ti+B4C=4TiB+TiC. The microstructure and tensile property of TMCs was investigated in accordance with the reinforcement distribution with respect to the B4C size and content. The microstructure revealed that their amount of reinforcements was increased with increasing B4C content. The size and morphology of the in-situ reinforcements were quite different according to the BtC size. In-situ synthesized reinforcements resulting from fine B4C were very minute and distributed homogeneously when compared to the coarse B4C. It is obvious that as the reinforcement content increased, tensile and wear properties were increased. Moreover, the improvement of the tensile strength and ductility of the TMCs was caused by not only load transfer strengthening but also by matrix grain refinement and homogeneous distribution of the reinforcements. The wear property of TMCs by fine and coarse reinforcements shows different results. It is expected that the improvement of wear property by fine reinforcement were caused by the reduced interparticle spacing.