輕量中熵合金之合金改質開發、微結構及常溫機械性質研究

Most medium entropy alloys (MEAs) exhibit excellent mechanical properties, but their applications are limited because of their high density. This study explores a series of lightweight nonequiatomic Ti65(AlCrNbV)35-xZrx (x =0 3, 5, 7, and 10) MEAs with low density, high strength, and high ductility. To achieve solid solution strengthening, Zr with a large atomic radius was used. The density of the MEAs was revealed to be approximately 5 g/cm3, indicating that they were lightweight. Through an X-ray diffraction analysis, the MEAs were revealed to have a single body-centered cubic structure in the as-cast state. In terms of mechanical properties, all the as-cast MEAs with Zr additions achieved excellent performance (>1000 MPa tensile yield strength and 20% tensile ductility). Overall, the Ti65(AlCrNbV)28Zr7 MEAs exhibited an optimum combination of mechanical properties (yield strength > 1200 MPa, plastic strain > 15%). According to the results mentioned above, the Ti65(AlCrNbV)28Zr7 MEAs demonstrate considerable potential for energy and transportation applications.