The Influence of Heat Treatment on Microstructure and Properties of Selective Laser Melting CuCrZr Alloy

Abstract

The effects of different heat treatment processes on the properties of selective laser melting (SLM) CuCrZr alloy are investigated toenhance its overall performance. Solution treatment (ST) results in recrystallized grains, leading to an increase in electrical conductivity to 45.36% IACS and a decrease in tensile strength to 221.8 MPa compared to SLM CuCrZr alloys.  Solution aging treatment (SAT) further improves the conductivity to 83.12% IACS and the tensile strength to 335.6 MPa. The optimal combination of electrical conductivity (72.82% IACS) and tensile strength (611.3 MPa) is achieved through direct aging treatment (DAH) at 480 °C for 2 h. With increasing aging temperature and time, the electrical conductivity initially increases rapidly and then plateaues, while the tensile strength exhibits an initial increase followed by a decrease. The proportion of precipitated phase gradually increases with longer aging time. Coherent precipitation occurs between the phase and the matrix at 480 °C for 120 min, while at 480 °C for 360 min, both face‐centered cubic and body‐centered cubic precipitates coexist with an incoherent relationship with the matrix. Overall, DAH proves effective in enhancing the properties of SLM CuCrZr alloy, with precipitation strengthening serving as the primary mechanism for improving its performance.