Research on the thermal stability of a near α titanium alloy before and after laser shock peening

The room-temperature tensile properties and thermal stability of Ti834 alloy before and after laser shock peening (LSP) were investigated. Micro-hardness measurement of the untreated and LSP treated specimens were carried out by using a Vickers indenter. The characteristic of microstructures were analyzed by TEM. The results show that both of the strength and ductility decrease for the 600 °C/100 h exposed Ti834 alloy, especially the decrease of ductility is more pronounced than that of strength. The strength and micro-hardness of Ti834 alloy can be improved by LSP, which is attributed to the high-density dislocation and dislocation-cell formation in the near-surface of the specimen. LSP treatment has a detrimental effect on the thermal stability of Ti834 alloy because of the formation of high density defects in the surface of the alloy.