Lin Wei-Chih, Lien Yi-Wen, Moreau Louis Etienne, Murakami Hideyuki, Lo Kai-Chi, Gorsse Stéphane, Yeh An-Chou
Department of Materials Science and Engineering, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu 300044, Taiwan.
Centre National de la Recherche Scientifique (CNRS), University Bordeaux, Bordeaux INP, ICMCB, UMR 5026, F-33600 Pessac, France.
Materials (Basel). 2024 Sep 18;17(18):4579. doi: 10.3390/ma17184579.
The oxidation of six NbTi-i refractory medium- and high-entropy alloys (NbTi + Ta, NbTi + CrTa, NbTi + AlTa, NbTi + AlMo, NbTi + AlMoTa and NbTi + AlCrMo) were investigated at 1000 °C for 20 h. According to our observation, increased Cr content promoted the formation of protective CrNbO and CrO oxides in NbTi + CrTa and NbTi + AlCrMo, enhancing oxidation resistance. The addition of Al resulted in the formation of AlTi-rich oxide in NbTi + AlTa. Ta addition resulted in the formation of complex oxides (MoTiTaO and TiTaO) and decreased oxidation resistance. Meanwhile, Mo's low oxygen solubility could be beneficial for oxidation resistance while protective CrO/CrNbO layers were formed. In NbTi + Ta, NbTi + AlTa and NbTi + CrTa, a considerable quantity of Ti-rich oxide was observed at the interdendritic region. In NbTi + AlCrMo, the enrichment of Cr and Ti at the interdendritic region could fasten the rate of oxidation. Compared to the recent research, NbTi + AlCrMo alloy is a light-weight oxidation-resistant alloy (weight gain of 1.29 mg/cm at 1000 °C for 20 h and low density (7.2 g/cm)).
研究了六种NbTi基难熔中高熵合金（NbTi + Ta、NbTi + CrTa、NbTi + AlTa、NbTi + AlMo、NbTi + AlMoTa和NbTi + AlCrMo）在1000℃下氧化20小时的情况。根据我们的观察，在NbTi + CrTa和NbTi + AlCrMo中，Cr含量的增加促进了保护性CrNbO和CrO氧化物的形成，增强了抗氧化性。Al的添加导致在NbTi + AlTa中形成富AlTi氧化物。Ta的添加导致形成复合氧化物（MoTiTaO和TiTaO）并降低了抗氧化性。同时，在形成保护性CrO/CrNbO层时，Mo的低氧溶解度可能有利于抗氧化。在NbTi + Ta、NbTi + AlTa和NbTi + CrTa中，在枝晶间区域观察到大量富Ti氧化物。在NbTi + AlCrMo中，枝晶间区域Cr和Ti的富集可能加快氧化速率。与最近的研究相比，NbTi + AlCrMo合金是一种轻质抗氧化合金（在1000℃下20小时重量增加1.29 mg/cm²且密度低（7.2 g/cm³））。
