Experimental study on the morphology and hardness variation of TiAl alloy at different heat treatment cycles

Abstract

This work aims to study the morphology of γ-TiAl alloy and its dependence on the hardness value. It was observed that there was a change in the hardness value when the specimens with the absence and presence of alloying elements were exposed to different heat treatment cycles. The specimen with alloying elements introduced to heat treatment cycle 2 faced an increment in hardness value by 5.28 HV10 with respect to the specimen without alloying elements. This effect became salient because of the age-hardening factor that superseded the existence of boron as a grain refiner. The formation of required phases was confirmed by the XRD (X-ray diffraction) test. Correspondingly, the optical microscope and scanning electron microscope tests corroborated the results obtained from the Micro-Vickers hardness test.