摘要
In order to improve the comprehensive properties of the Cu-11.9Al-2.5Mn shape memory alloy(SMA),multilayer graphene(MLG)carried by Cu_(51)Zr_(14)inoculant particles was incorporated and dispersed into this alloy through preparing the preform of the cold-pressed MLG-Cu_(51)Zr_(14)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.
为了提高Cu-11.9Al-2.5Mn形状记忆合金(SMA)的综合性能,通过制备多层石墨烯(MLG)-Cu_(51)Zr_(14)复合粉末冷压预制体,将MLG由Cu_(51)Zr_(14)孕育剂颗粒承载后添加并分散于该合金中。在所制备的新型MLG/Cu-Al-Mn复合材料中,碎片状或絮状的MLG与Cu-Al-Mn基体结合良好。MLG可以阻碍Cu-Al-MnSMA晶粒的粗化,并在MLG/Cu-Al-Mn界面附近产生热失配位错。MLG/Cu-Al-Mn复合材料的阻尼和力学性能显著提高,当MLG的含量达到0.2%(质量分数)时,其最高室温阻尼为0.0558,抗拉强度为801.5 MPa,伸长率为10.8%,硬度为HV 308。基于深入的显微组织观察,结合内耗理论以及金属的强韧化理论,对相关机理进行讨论。
基金
supported by the Natural Science Foundation of Hebei Province,China(No.E2021202017)
the National Natural Science Foundation of China(No.52061038)
the Foundation Strengthening Program,China(No.2019-JCJQ-ZD-142-00)
the Hebei Province Graduate Innovation Funding Project,China(No.CXZZBS2022032)
the Jiangsu Provincial Policy Guidance Program(Special Project for the Introduction of Foreign Talents)Talent Introduction Program,China(No.BX2021024)
the Science Plan Foundation of Tianjin Municipal Education Commission,China(No.2021KJ026)。
