Processing maps of Ti662 unreinforced and reinforced with TiC particles according to dynamic models

Ti-6Al-6V-2Sn produced by powder metallurgy by Dynamet unreinforced (CermeTi (R)-C-662) and reinforced with 12 vol.% of TiC particles (CerrneTi (R)-C-12-662), and ingot Ti662 are deformed at high temperatures. The processing maps of these materials are derived using the dynamic material model (DMM) developed by Prasad et al., and the modified DMM developed by Murty and Rao. Although both models result in similar power dissipation values, the instability zones predicted by them are quite different. The processing maps predicted by the modified DMM can be correlated to the deformation behaviour of these materials, with respect to the shape of their flow curves and to their microstructure after deformation. The concentration of stresses produced during compression is released by cracking at the triple junction of grain boundaries in the CermeTi (R)-C-662, whereas in the CermeTi (R)-C-12-662 by fracture or debonding of the reinforcing particles. (C) 2007 Elsevier B.V. All rights reserved.