Analytical And Numerical Analysis Of Compressive Deformation Behavior Of Cast In-Situ Tial Matrix Composites Reinforced With Carbide Particles

Analytical and numerical analyses of room temperature compressive deformation behavior of cast in-situ composites with the chemical compositions Ti-44.6Al-7.9Nb-3.6C-0.7Mo and Ti-44.9Al-7.5Nb-4.9C-0.6Mo0.1B ( at%) were performed. The microstructural evaluation was carried out by scanning electron microscopy (SEM) and SEM in back scattered electron (BSE) mode. The uniaxial room temperature compression tests were carried out at an initial strain rate of 1x10(-4) s(-1) up to a true strain of 15 %. The finite element analysis (FEA) of local equivalent strains supported by quantitative microstructural analysis indicates that the mean length of major axis of fragmented primary carbide particles decreases with increasing local equivalent strain in the compression specimens. The observed differences in compressive work hardening behavior are related to the initial non-uniform deformation, cracking of the primary carbide particles, propagation of cracks in the intermetallic matrix and finally to disintegration of the compressive specimens.