Improving comprehensive properties of Cu-11.9Al-2.5Mn shape memory alloy by adding multi-layer graphene carried by Cu51Zr14 inoculant particles
(1. School of Mechanical Engineering, Tianjin University of Technology and Education, Tianjin 300222, China;
2. Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China;
3. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
4. Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510651, China)
2. Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology, School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300130, China;
3. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
4. Institute of New Materials, Guangdong Academy of Sciences, Guangzhou 510651, China)
Abstract: In order to improve the comprehensive properties of the Cu-11.9Al-2.5Mn shape memory alloy (SMA), multilayer graphene (MLG) carried by Cu51Zr14 inoculant particles was incorporated and dispersed into this alloy through preparing the preform of the cold-pressed MLG-Cu51Zr14 composite powders. In the resultant novel MLG/Cu-Al-Mn composites, MLG in fragmented or flocculent form has a good bonding with the Cu-Al-Mn matrix. MLG can prevent the coarsening of grains of the Cu-Al-Mn SMA and cause thermal mismatch dislocations near the MLG/Cu-Al-Mn interfaces. The damping and mechanical properties of the MLG/Cu-Al-Mn composites are significantly improved. When the content of MLG reaches 0.2 wt.%, the highest room temperature damping of 0.0558, tensile strength of 801.5 MPa, elongation of 10.8%, and hardness of HV 308 can be obtained. On the basis of in-depth observation of microstructures, combined with the theory of internal friction and strengthening and toughening theories of metals, the relevant mechanisms are discussed.
Key words: Cu-Al-Mn shape memory alloy; multilayer graphene (MLG); microstructure; interface; damping; mechanical properties