Effect of powder batches and laser power on the microstructure and properties of as-built and heat-treated Laser Powder Bed Fusion CuCrZr samples

Recently, we showed that >99% dense CuCrZr parts can be produced by Laser Powder Bed Fusion (L-PBF) process using a large power range (270 to 480W) [1,2]. The as-built (AB) microstructure is anisotropic, showing columnar grains aligned along building direction (BD). After a solution annealing and age hardening (SA+AH), solidification cells disappear and the dislocations density decrease, whereas partial recrystallization, twins and Cr nano-precipitates are observed. Even if the microstructure is not fully similar to wrought CuCrZr one, yield strengths are equivalent. This work aimed to develop further the process by: (i) evaluating the impact of incoming powders and lasing parameters on the AB microstructure, (ii) analyzing the microstructural effects of SA+AH and (iii) comparing the mechanical, thermal and electrical properties in both conditions for four powders