Effects of build orientation and heat treatment on microstructure and properties of Cu-Cr-Zr alloy manufactured by laser powder bed fusion

Laser powder bed fusion was utilized to manufacture Cu-1Cr-0.19Zr alloys with varied build orientations (0 degrees and 90 degrees). The build orientation affected the grain orientation and texture of the studied alloy. Cu-1Cr-0.19Zr alloy manufactured in the 0 degrees orientation exhibited an intensive < 110 > texture. Aging the as-fabricated alloy reduced dislocations and dislocation cells and led to the formation of recrystallized grains and face-centered-cubic structured Cr precipitates (2-7 nm). The mechanical properties and conductivity of the Cu-1Cr-0.19Zr alloy increased with the aging time. The conductivity enhancement was ascribed to the decrease of defect, and im-purity scattering. Meanwhile, texture led to the anisotropy of the mechanical property in the vertical and hor-izontal planes. The optimal aging temperature and holding time were 500 degrees C and 30 min, the microhardness, electrical conductivity, and yield strength (compression) reached 220.6 HV, 62.1% IACS (International Annealed Copper Standard), and 540 MPa. The softening temperature of the peak-aged Cu-1Cr-0.19Zr alloy was 580 degrees C, which was enhanced by dispersed Cr precipitates. These findings guide to fabrication of Cu-Cr-Zr alloys by laser -assisted additive manufacturing.