NbSi based alloys are expected to become the application materials for high pressure turbine blades of aircraft engines. This paper investigates the impact of Ta addition on room temperature fracture toughness and isothermal oxidation behavior at 1250 °C of four NbSi based alloys with compositions of Nb-16Si-20Ti-8Zr-4Hf-1.5Al-Ta ( = 0, 1, 2, and 4 at.%) fabricated through vacuum non-consumable arc-melting. The results show that the room temperature fracture toughness and 1250 °C oxidation resistance of the alloys increase first and then decrease with the addition of Ta element. The room temperature fracture toughness of 1Ta alloy is the best, reaching 17.1 MPa·m. Adding a moderate amount of Ta (1 at.%) significantly enhances the alloy's oxidation resistance, but an excessive Ta content diminishes this enhancement. This research has obtained a Nb-16Si-20Ti-8Zr-4Hf-1.5Al-1Ta alloy with high room temperature fracture toughness and excellent high temperature oxidation resistance simultaneously, which provide an ideal path for designing NbSi alloys with superior comprehensive properties.

中文翻译：

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适当的Ta含量添加策略同时提高Nb[sbnd]Si基合金的高温抗氧化性和室温韧性


NbSi基合金有望成为航空发动机高压涡轮叶片的应用材料。本文研究了 Ta 添加量对成分为 Nb-16Si-20Ti-8Zr-4Hf-1.5Al-Ta (= 0, 1, 2) 的四种 NbSi 基合金室温断裂韧性和 1250 °C 等温氧化行为的影响。 ，和 4 at.%）通过真空非自耗电弧熔炼制造。结果表明，随着Ta元素的添加，合金的室温断裂韧性和1250℃抗氧化性能先增加后降低。 1Ta合金的室温断裂韧性最好，达到17.1 MPa·m。添加适量的 Ta (1 at.%) 可显着增强合金的抗氧化性，但过量的 Ta 含量会减弱这种增强作用。本研究获得了同时具有高室温断裂韧性和优异高温抗氧化性能的Nb-16Si-20Ti-8Zr-4Hf-1.5Al-1Ta合金，为设计具有优越综合性能的NbSi合金提供了理想的途径。