As-cast Tix(AlVCr)100-x light-weight medium entropy alloys with high strength and uniform compressive plasticity
(1. College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China;
2. School of Intelligent Manufacturing and Information, Jiangsu Shipping College, Nantong 226010, China;
3. Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China;
4. National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China)
2. School of Intelligent Manufacturing and Information, Jiangsu Shipping College, Nantong 226010, China;
3. Laboratory for Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900, China;
4. National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China)
Abstract: The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Tix(AlVCr)100-x medium entropy alloys was studied by compressive tests, X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results suggest that yield strength increases and then decreases with the increment of Ti content. The Ti60(AlVCr)40 alloy has the best combination of high strength of 1204 MPa and uniform plastic strain of 70%, possessing a high specific yield strength of 255 MPa·cm3/g. The enhancement of strength is mainly attributed to the synergic effects of solid-solution and coherent nano-precipitation strengthening, while dislocation motion such as dislocation pinning, entanglement and dislocation cells significantly increases the strain-hardening capacity.
Key words: TiAlVCr medium entropy alloy; solid solution strengthening; b2 precipitate; strain hardening behavior