Preparation of high-mechanical-property medium-entropy CrCoNi alloy by asymmetric cryorolling
(1. State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, China;
2. College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China;
3. Light Alloys Research Institute, Central South University, Changsha 410083, China;
4. Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW 2052, Australia;
5. PDPM Indian Institute of Information Technology, Design and Manufacturing, Jabalpur 482005, India;
6. Laboratory of Mechanics of Gradient Nanomaterials, Nosov Magnitogorsk State Technical University, Magnitogorsk 455000, Russia)
2. College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China;
3. Light Alloys Research Institute, Central South University, Changsha 410083, China;
4. Mark Wainwright Analytical Centre, University of New South Wales, Sydney, NSW 2052, Australia;
5. PDPM Indian Institute of Information Technology, Design and Manufacturing, Jabalpur 482005, India;
6. Laboratory of Mechanics of Gradient Nanomaterials, Nosov Magnitogorsk State Technical University, Magnitogorsk 455000, Russia)
Abstract: In order to obtain good strength-plasticity synergy for a medium entropy alloy (MEA) CrCoNi, cold rolling, asymmetric rolling, cryorolling and asymmetric-cryorolling with subsequent annealing at different temperatures were conducted. The results showed that the asymmetric-cryorolled alloy achieved a high strength of over 1.6 GPa. After annealing at 1073 K, it retained a high strength of ~1 GPa while the elongation reached nearly 60%. After annealing, the heterogeneous characteristics were formed in asymmetric-cryorolled samples, which were found to be more distinct than those of the samples subjected to asymmetric rolling. This resulted in the generation of high strength and ductility.
Key words: medium entropy alloy; heterogeneous structure; annealing; mechanical properties; asymmetric cryorolling