Study on Microstructure and Tensile Properties of High Cu Content CuNiCrMnAl Alloys in Cast and Annealed States

The relationship between the microstructure and tensile properties of (Cu₇₅Ni₁₀Cr₁₀Mn₅)₉₅Al₅ multi-principal alloy was studied. It is found that the microstructure of the as-cast alloy is composed of a phase with face-centered cubic（FCC） structure and phase with body-centered cubic（BCC） structure. After 900 ℃/1 h annealing, the tensile strength of the alloy attains 516 MPa, and the total elongation reaches 22%. The as-annealed alloy macroscopically has dual-phase microstructure of FCC and BCC structure, while some micron-scale phase with BCC structure is also precipitated from the phase with FCC structure. Therefore, the alloy can exhibit superior strength, indicating that the microstructure of the alloy is stable to some extent.