Fracture behavior of low cycle fatigue and dwell fatigue of Ti6242 titanium alloy under high load

Abstract

As one kind of near alpha titanium alloys with excellent mechanical properties, Ti6242 alloy always shows the“dwell fatigue”characteristic, which is similar to other near α or α+β titanium alloys, especially at near room temperature. In this study, the low cycle fatigue and dwell fatigue tests under high load were designed according to the law of dwell fatigue sensitivity rising with the increase of test load. Combining with microstructure observation, mechanical property characterization and failure fracture analysis, the relationship between the microstructure and fracture behavior under high load low cycle fatigue and dwell fatigue tests was analyzed systematically. By summarizing the characteristics of failure fracture under room temperature tensile, high load low cycle fatigue test and high load dwell fatigue test, also comparing the dwell fatigue sensitivity of the Ti6242 alloy in this study with other Ti6242 alloys and other titanium alloys under different loading conditions, it is proved that increasing the fatigue load is a feasible way to characterize the dwell fatigue sensitivity of Ti6242 alloy.

Keywords

• Titanium
• dwell fatigue
• high load
• fracture analysis