Influences of the Welding Heat Input and the Repeated Repair Welding on Ti-3Al-2.5V Titanium Alloy

The primary purpose of this study was to determine the effects of gas tungsten arc welding heat input on the high-temperature tensile properties, toughness, and microstructural features of titanium alloy Ti-3Al-2.5V. The secondary objective was to examine the effect of the repeated repair welding on the properties of the alloy. It was also found that the mechanical properties progressively decreased with increasing the repair welding cycles, especially in the case of the weldment after the first welding repair. It was observed that the sizes of the acicular alpha' and prior beta grain boundaries as well as the volume fraction of the acicular alpha' phases increased with increasing the welding heat input. In addition, the amount and size of the acicular alpha' phases were found to increase with increasing the repair welding cycles.