Abstract The effect of specimen shape, degree of deformation by forging, surface contam-ination of O_2, chemical composition and microstructure on the brittle fracture ofTi-679 alloy subjected to creep test at 450℃ for 100h have been studied. Thethermal stability of the alloy close to α-region was not only related to the alloycomposition, but also to the microstructure formed in the process of deformation.The appearance of the rolled β structure was regarded as the main cause in dete-riorating the thermal stability of this alloy.
[1] Erdeman, V. J. and Ross, E. W., The Science Technology and Application of Titanium, edited by Jaffee, R. I. and Promisel, N. E., 1970, Pergamon Press, London, p. 829． [2] Shamblem, C. E. and Redden, T. K., ibid., p. 199． [3] Coyne, T. E., ibid., p. 97． [4] Green, T. E. and Minton, C. D. T., ibid., p. 111． [5] Rosenberg, H. W., ibid., p. 851．
