Effects of minor B additions on tensile strength, fracture toughness and oxidation resistance of Nb–Si based alloys
添加少量 B 对 Nb-Si 基合金抗拉强度、断裂韧性和抗氧化性的影响
Nb–Siベースの合金の引張強度、破壊靭性、および耐酸化性に及ぼす少量のB添加の影響
Nb-Si 기반 합금의 인장 강도, 파괴 인성 및 내산화성에 대한 소량의 B 첨가 효과
Efectos de adiciones menores de B sobre la resistencia a la tracción, tenacidad a la fractura y resistencia a la oxidación de aleaciones basadas en Nb-Si
Effets des ajouts mineurs de B sur la résistance à la traction, la ténacité à la rupture et la résistance à l'oxydation des alliages à base de Nb-Si
Влияние незначительных добавок B на предел прочности при растяжении, вязкость разрушения и стойкость к окислению сплавов на основе Nb–Si
Guangxin Sun 孙井永, Lina Jia 贾丽娜, Yu Wang, Zuheng Jin, Hu Zhang 张虎
School of Materials Science and Engineering, Beihang University, Beijing, 100191, China
中国 北京 北京航空航天大学材料科学与工程学院
Progress in Natural Science: Materials International, 7 January 2022
Abstract
The effects of minor additions of B on microstructure, ambient tensile strength, fracture toughness and high-temperature oxidation resistance of Nb–Si based alloys were investigated. The added contents were designed as 0.05, 0.10 and 0.20 at.%. The results show constituent phases in 0.05B and 0.20B alloys were Nbss, α-Nb₅Si₃; while only 0.10B alloy consisted of γ-Nb₅Si₃. Minor B was prioritized into Nbss and redundant one dissolved into silicide enhanced volume fraction of the silicide.
With increasing concentrations of boron, the microstructure was refined at first and then coarsened, while the tensile strength was enhanced remarkably. Compared with other two alloys, the 0.10B alloy containing γ-Nb₅Si₃ shows both the best fracture toughness and oxidation resistance. The important roles of γ-Nb₅Si₃ in balancing overall properties are emphasized.