Mechanical and Microstructural Analyses of Three Layered Cu-Ni-Zn/Cu-Zr/Cu-Ni-Zn Clad Material Processed by High Pressure Torsioning (HPT)

Abstract

Cu-Ni-Zn/Cu-Zr/Cu-Ni-Zn three layered clad plates were prepared by high pressure torsioning (HPT) at room temperature and theirmicrostructural and mechanical analyses wereperformed. No intermetallic compounds were observed at Cu-Zr/Cu-Ni-Zn interfaces in the as-HPTed and heat-treated Cu/Ni-Zn/Cu-Zr/Cu-Ni-Zn clad plates. The strength of as-HPTed clad plate reached up to 610 MPa with the ductility of 14%. After heat treatment at 500oC, Cu-Ni-Zn/Cu-Zr/Cu-Ni-Zn clad plate exhibited the strength up to 490 MPa and the ductility of 28 %. The clad plate fractured all together at the same time without discontinuous drop of the stress until final fracture. The excellent mechanical reliability and the good interfacialbonding strength can be attributed to the absence of detrimental interfacial reaction compounds between Cu-Ni-Zn and Cu-Zr.