High-temperature oxidation behavior of Nb67-xW15Si18Hfx(x=0, 5 and 10) alloys
(1.北京市北京航空航天大学材料科学与工程学院
2.School of Materials Science and Engineering, South Campus, Shandong University, Ji’nan 250061, China
3.School of Materials Science and Engineering,Beijing University of Aeronautics and Astronautics, Beijing 100083, China)
2.School of Materials Science and Engineering, South Campus, Shandong University, Ji’nan 250061, China
3.School of Materials Science and Engineering,Beijing University of Aeronautics and Astronautics, Beijing 100083, China)
Abstract: The oxidation behaviors of Nb67-xW15Si18Hfx (x=0, 5, 10) alloys were studied at 1 250 ℃ in air. It is found that the Nb67W15Si18 alloy has the best oxidation resistance among the three alloys; and Hf addition is harmful to the oxidation resistance of the Nb67W15Si18 alloy. The oxides formed on the Nb67W15Si18 alloy are mainly Nb12WO33 and NbO2, and that on the Nb62W15Si18Hf5 and Nb57W15Si18Hf10 alloys is Nb2O5. Effect of Hf on the oxidation behavior of the Nb67-xW15Si18Hfx alloys has been discussed based on microstructures and kinetics of oxidation.
Key words: Nb-Si based alloys; Nb67-xW15Si18Hfx alloys; high-temperature oxidation; oxidation resistance; oxide