Microstructure and Properties of a Hot Rolled-Quenched Cu-Cr-Zr-Mg-Si Alloy

The microstructure and properties of a hot rolled-quenched Cu-Cr-Zr-Mg-Si alloy were investigated by transmission electron microscopy observations, micro-hardness and tensile strength testing, and electrical conductivity measurement. The results show that the hot rolling-quenching (HR-Q) process and subsequent thermomechanical treatments are successfully developed to manufacture Cu-Cr-Zr-Mg-Si alloy strips. Solution treatment can be finished during the HR-Q process, and good combinations of strength, conductivity, and softening resistance are obtained for the thermomechanically treated strips. Ordered fcc structure precipitates which exhibit a cube-on-cube orientation relationship with the matrix are responsible for the improvements of properties. The properties of hot rolled-quenched Cu-Cr-Zr-Mg-Si alloy strips can be further improved by two-step rolling and aging process. The improvements of properties are attributed to the interactions of precipitation strengthening and strain hardening.