ECAP对连铸Cu-Ag合金断口形态及力学性能的影响

Effect of ECAP on Fracture Morphology and Mechanical Properties of Cu-Ag Alloys Produced by Continuous Casting

摘要:

采用连续铸造和等径角挤压变形(ECAP)加工集成技术制备Cu-Ag合金，研究其力学性能和相应的拉伸断口形态。研究发现，Cu-Ag合金的强度随着ECAP加工道次和Ag含量的增加而增加，而延伸率却下降。连续铸造和ECAP加工的合金与传统浇铸和ECAP加工的合金相比，缩颈前静态韧性有所提高。同时发现，只有连铸的Cu-Ag合金在断裂前表现出缩颈现象，而经ECAP挤压后试样的断裂变为剪切模式，随着ECAP道次的增加出现不同的剪切断裂角。基于实验结果，讨论了经ECAP挤压后连铸Cu-Ag合金的拉伸断裂机制

Abstract:

Cu-Ag alloys were prepared by an integrated technique of continuous casting and equal channel angular pressing (ECAP). Their mechanical properties and tensile fracture morphology were studied. Results show that the strength of Cu-Ag alloys increases with the increase of ECAP passes and Ag content, but their elongation decreases. Static toughness of ECAPed alloys by continuous casting is improved compared with that of ECAPed alloys by traditional casting before necking. Meanwhile, it is found that the alloys only by continuous casting exhibits necking before failure, while the alloys subjected to ECAP fail in shear mode with different shear fracture angles as the number of ECAP passes increases. Based on the experimental results, the tensile failure mechanisms of the ECAPed Cu-Ag alloys by continuous casting were discussed