Thermally Activated Deformation of Ti–C Alloys below 0.4Tm

• Published in: Transactions of the Japan Institute of Metals Vol. 15; no. 1; pp. 11 - 17
• Main Authors: Okazaki, K., Morinaka, K., Conrad, H.
• Format: Journal Article
• Language: English
• Published: The Japan Institute of Metals 1974
• ISSN: 0021-4434; 2432-4701
• DOI: 10.2320/matertrans1960.15.11

To ascertain the rate controlling mechanism for the plastic flow of Ti–C alloys with 0.07∼0.36 at%C, the effects of temperature, strain rate and carbon in interstitial solid solution on the yield and flow stresses were studied in the temperature range of 77 to 700°K. The effect of carbon on the thermal component of the flow stress σ* is described by σ*=αμ\sqrtCi, where α is a constant which increases with decreasing temperature, μ the shear modulus C66 and Ci the interstitial carbon content. The Gibbs free energy of activation for plastic flow is 0.80 ev at 515°K regardless of the carbon concentration. A force-activation distance curve was constructed by utilizing the experimental data yielding fim*=52×10−6 dynes and x0*=1.3b, which are in accord with the thermally activated overcoming of interstitial carbon atoms by dislocation as the rate controlling mechanism.