Microstructure and properties in CuCrZr alloy fabricated by selective laser melting with different heat treatment

Abstract

CuCrZr alloy is promising in many industrial applications because of its extremely high thermal conductance and conductivity. In this paper, the effects of aging heat treatment temperature and time on microstructure and mechanical properties of CuCrZr alloy fabricated by selective laser melting were investigated. The mechanical properties of CuCrZr alloy after aging heat treatment were investigated by high temperature tensile experiments. The results showed that the aging treatment did not change the grain size and morphology of CuCrZr alloy. Scanning electron microscope (SEM) and transmission electron microscope (TEM) observation showed that Cr precipitated in the microstructure after aging treatment and caused precipitation strengthening, which is an important factor for the mechanical properties of CuCrZr alloy manufactured by SLM. After aging heat treatment, the hardness of CuCrZr alloy increases to 185.7 ± 1.82HV. Tensile test results show that aging heat treatment can greatly improve the tensile strength of CuCrZr fabricated by SLM, and the maximum value is 515.5 ± 12.8 MPa. At the same time, the tensile property of CuCrZr alloy decreases with the increase of temperature, but can still reach 319.34 ± 0.49 MPa at 250 ℃.

Keywords

• Selective laser melting
• Heat treatment
• CuCrZr
• Microstructure
• Mechanical properties