SYNTHESIS OF NEAR NET SHAPE HIGH-DENSITY TIB TI COMPOSITE/

TiB/T-1 composite were produced by SHS (self propagating high temperat ure synthesis) under conditions of PHIP (pseudo-hot isostatic pressing ). The synthesis conditions were optimized to produce highly dense mat erials conforming a high volume fraction of TIE. Self-propagating reac tion of the Ti and B powders occurred above the alpha-to beta-Ti trans formation temperature (1155 K). The composites consist of Ti matrices with dispersed TiB reaction products of 2-30 mu m size. Near fully den se composites with a TiB/Ti volume ratio of 33-44 vol.% were synthesiz ed for B/Ti atomic ratios of 0.3-0.4 at pseudo isostatic pressures of 100 MPa. The Vickers hardness and fracture stress of the composites ar e 5.6-7.1 and 2.1-2.3 GPa, respectively, and the wear of the composite is approximately 7-9% of the Ti and Ti-6A1-4V. (C) 1997 Elsevier Scie nce S.A.