LOW CYCLE FATIGUE IN TITANIUM ALUMINIUM FORMED BY CENTRIFUGAL SPRAY DEPOSITION
(1.Department of Materials, Fuzhou University, Fuzhou 350002, P. R. China;
2.School of Materials Science and Engineering, Xi′an Jiaotong University, Xi′an 710049, P. R. China;
3.State Key Laboratory For Fatigue and Fracture of Materials,Institute of Metal Research, Chinese Academy of Sciences, Shenyang110015, P. R. China)
2.School of Materials Science and Engineering, Xi′an Jiaotong University, Xi′an 710049, P. R. China;
3.State Key Laboratory For Fatigue and Fracture of Materials,Institute of Metal Research, Chinese Academy of Sciences, Shenyang110015, P. R. China)
Abstract: The push-pull low cycle fatigue (LCF) behaviors of Ti-48Al-2Mn-2Nb(mole fraction, %), which was formed by centrifugal spray deposition (CSD) under a low pressure vacuum condition, were investigated under the control of total cyclic strain amplitude at ambient temperature. The results show that the available cyclic strain amplitude regions of TiAl alloy are very narrow,Δεt/2 equals 0.1%~0.25%, and no cyclic hardening or softening are observed during low cycle fatigue processes. The fatigue lives of CSD samples can be improved by hot isostatic pressing (HIP). The characteristics of dislocation configurations of samples experienced different strain amplitudes have been analyzed by means of transmission electron microscopy (TEM).
Key words: centrifugal spray deposition (CSD) Ti-48Al-2Mn-2Nb low cycle fatigue