MICROSTRUCTURE AND DEFORMATION OF TIB+TI2C REINFORCED TITANIUM MATRIXCOMPOSITES

A novel technique known as combustion assisted synthesis was utilised for the fabrication of titanium carbide + titanium boride reinforced t itanium matrix composites. This technique resulted in a homogeneous di stribution of rodlike (TiB) and equiaxed (Ti2C) reinforcements in a fi ne grained (1-2 mu m) titanium matrix, with a clean matrix/particle in terface. The deformation behaviour of the composites and the control s ample of titanium were studied in the temperature range 298-873 K and strain rate range 2 x 10(-5)-2 x 10(-2) s(-1). Tests indicated that th e composites were more deformable in compression and the values of yie ld strength of the composites increased with volume fraction of reinfo rcements, being approximately x 3-5 that of he control titanium. Fract ographic analysis indicated that the composites failed in tension due to particle cracking, whereas the failure mode of the control titanium was dimpled fracture.