Effect of Microstructure on Impact Resistance and Machinability of TiAl Alloys for Jet Engine Turbine Blade Applications

The impact resistance and machinability of TiAl alloys, which are used for jet engine turbine blades, critical ensuring reliability reducing manufacturing costs. This study investigated the effects microstructure on these properties using Ti–Al–Cr ternary alloys via Charpy tests at room temperature 700 °C performing cutting a face mill with cemented carbide tools. As result, it was confirmed that six types typical microstructures namely, fine FL, coarse L + γ, γ β, could be formed by varying Al Cr concentrations heat-treatment conditions. Impact each exact opposite trends to other, FL having best but poor machinability. Meanwhile, has weakest resistance. no major drawbacks, including creep strength. TiAl4822, currently in LEAP (leading edge aviation propulsion) is almost single-phase microstructure, we assumed manufacturers chose this improve thus reduce cost. However, because lowest resistance, caution should exercised when applying other engines different operating environment. On hand, containing β phase inferior all aspects, Thus, questionable use TiAl-forged materials residual small-sized products can manufactured casting.