Contribution of Zr to strength and grain refinement in Cu Cr Zr alloy

Abstract The mechanical properties and microstructure transformation of Cu Cr Zr alloys obtained by upward continuous casting with varying Zr contents were studied by optical microscopy (OM), electron backscattered diffraction (EBSD) and transmission electron microscopy (TEM) after cold drawing with different strain and heat treatment. The results show that good strength can be obtained through cold drawing with suitable heat treatment. The peak tensile strength can achieve 587.8 MPa and the peak yield strength can reach 499.6 MPa; The difference of yield strength of Cu Cr Zr alloy during cold drawing deformation becomes larger with the increase of Zr element content when the strain gradually improves; The increase of the Zr element will promote the recrystallization of the alloy at aging after cold drawing, refining the crystal grains. It contributes about 70% of the increase in strength, act as a fine grain strengthening effect, increasing the strength of the alloy.