Comparison of low cycle fatigue performance of several [0] Sigma fibre reinforced titanium matrix composites

The low cycle fatigue behaviour of four SiC fibre reinforced titanium matri x composites (TMCs) is examined at temperatures relevant to gas-turbine com pressor components. It is found that, in the high cyclic stress/short life regime, the fatigue performance of the four TMCs is similar at each tempera ture. At lower stresses, however, more relevant to the gas-turbine compress or application, fatigue lives of Ti-6-4/SM1240, Timetal 834/SM1140+ and Tim etal 834/SM1240 TMC all become significantly inferior to those of Ti-6-4/SM 1140+ at temperatures of 450 degreesC and above. This inferiority is attrib uted to intergranular embrittlement of the Timetal 834 matrix, the high cre ep resistance of the Timetal 834 matrix and due to an as yet unexplained we akening of the SM1240 fibre. (C) 2001 Elsevier Science Ltd. All rights rese rved.