不同铸造方法对Cu-12Sn-2Ni合金微观组织及性能的影响

Effects of Different Casting Methods on Microstructure and Properties of Cu-12Sn-2Ni Alloy

采用重力铸造、离心铸造制备了Cu-12Sn-2Ni合金,研究两种铸造方式对合金微观组织以及力学性能的影响。结果表明,重力铸造试样组织由α相、δ相所组成;离心铸造由于冷却速率快,导致亚稳相β′相的产生,细化了晶粒尺寸。离心铸造试样的抗拉强度可以达到378.84 MPa、伸长率为11.77%。对断口进行分析,发现在离心铸造试样中存在韧窝群,而在重力铸造试样中没有韧窝存在,这主要与晶粒尺寸、β′相的产生有关。

Cu-12Sn-2Ni alloy was prepared by gravity casting and centrifugal casting,and the effects of two casting methods on the microstructure and mechanical properties of the alloys were studied.The results showed that the gravity casting specimen structure was composed ofαphase andδphase.Due to the fast cooling rate,the centrifugal casting led to the generation of metastable phaseβ′phase,which refined the grain size.The tensile strength of the centrifugal casting specimens reached 378.84 MPa and the elongation was 11.77%.The fracture analysis showed that there was a group of dimples in the centrifugal casting specimen and no ligament fossa in the gravity casting specimen,which was mainly related to the grain size andβ′phase generation.