Ta元素对新型γ+γ'双相Ir基高温合金显微组织和力学性能的影响

γ'-Ir₃(Al,W) phase-strengthened Ir-13W-6Al (at%) superalloys exhibit promising applications for aerospace industry. An experimental set-up was based on Ir-13W-6Al ternary superalloy and 2at%, 5at%, 8at% Ta elements were added. The effect of Ta on the microstructure evolution, the amount of γ' strengthening phase, the precipitation behavior, room/high-temperature mechanical properties and fracture characteristics of γ+γ' two-phase Ir-based superalloys were investigated. The results show that with the increasing Ta content, the volume fraction of γ' strengthening phase increases and the Vickers hardness/nano-hardness of the alloy after adding Ta is higher than that of the Ir-13W-6Al ternary superalloy. The addition of Ta improves the high-temperature mechanical properties of Ir-13W-6Al superalloys at 1300℃, and the increased compressive strength can be attributed to the precipitation of γ'-Ir₃(Al,W) phase and solid-solution strengthening of Ta. Ta effectively improves the room- and high-temperature properties of Ir-13W-6Al superalloys. This study provides experimental and theoretical guide for the development of novel γ+γ' two-phase Ir-based superalloys.