Mechanical and corrosion properties of lightweight (Ti60Cr30Nb10)100-xAlx medium-entropy alloys
(1. Guangdong Key Laboratory for Advanced Metallic Materials Processing, South China University of Technology, Guangzhou 510641, China;
2. National Engineering Research Center of Near-net-shape Forming for Metallic Materials, South China University of Technology, Guangzhou 510641, China;
3. Physical Metallurgy and Materials Design Laboratory, Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA, 15261, USA)
2. National Engineering Research Center of Near-net-shape Forming for Metallic Materials, South China University of Technology, Guangzhou 510641, China;
3. Physical Metallurgy and Materials Design Laboratory, Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, PA, 15261, USA)
Abstract: Microstructure, mechanical properties and corrosion behavior of lightweight (Ti60Cr30Nb10)100-xAlx (x=0, 5, 7.5 and 10, at.%) medium-entropy alloys (MEAs) were investigated in the as-cast and homogenized states. As the Al content increases from 0 to 10 at.%, all the as-cast MEAs consist of identical phase composition, i.e., a body-centered cubic (BCC) phase and a small amount of TiCr2 Laves phase. After the homogenization, all the homogenized MEAs show a single BCC phase. The (Ti60Cr30Nb10)95Al5 MEA shows the most excellent mechanical properties both in as-cast and homogenized states among the studied alloys, displaying yield strengths of ~1048 MPa and ~1017 MPa along with the compression strain exceeding 50%. Additionally, compared with the TC4 and the as-cast (Ti60Cr30Nb10)95Al5 alloys, the homogenized (Ti60Cr30Nb10)95Al5 alloy shows superior corrosion resistance due to its uniform microstructure and chemical composition.
Key words: medium-entropy alloy; lightweight alloy; microstructure; mechanical properties; corrosion behavior