HOT EXPLOSIVE CONSOLIDATION OF W-TI ALLOYS

High-density (98 pct TD) 95W-5Ti (wt pct) alloys have been fabricated by a combustion-synthesis-assisted hot explosive consolidation (CSA-HEC) technique. In the current procedure, a W + Ti powder compact is preheated by the heat released by a Ti + C exothermic combustion synthesis reaction and subsequently consolidated by pressure waves generated by the detonation of an explosive. The amounts of explosive charge, sample configuration, and molar ratio of exothermic material to sample were found to affect the degree of consolidation. Auxiliary temperature measurements were performed to determine the precompaction thermal history of the sample to obtain the optimum delay time for consolidation. As observed with scanning electron microscopy (SEM), the CSA-HEC microcomposites consist of W particles surrounded by a partially discontinuous Ti-rich matrix. Transmission electron microscopy (TEM) was also used to further characterize the W/Ti interfacial region. The pertinent features of the technique as well as those of the product microstructures are discussed.