Remarkable thermal stability of the Al-Ca-Ni-Mn alloy manufactured by laser-powder bed fusion

Microstructure and hardness of the Al-Ca-Ni-Mn alloy fabricated by laser-powder bed fusion were studied in as-built condition and after annealing at 200-400 degrees C for 3 h. A formation of pseudoeutectic cellular structure and outstanding hardness of 200 HV were reported in the initial state. A decrease in hardness down to 161 HV after exposure at 300 degrees C and no further degradation occurred after heating up to 400 degrees C. The softening was accompanied by the growth of primary phase up to-800 nm and eutectic phase to-90 nm. The latter had the most contribution into hardening that was explained by Orowan looping mechanism. (c) 2020 Elsevier B.V. All rights reserved.

Automated summary

The microstructure and hardness of the Al-Ca-Ni-Mn alloy fabricated by laser-powder bed fusion were studied in the as-built condition and after annealing at 200-400 degrees C for 3 hours. A decrease in hardness was observed after exposure at 300 degrees C, attributed to the growth of primary and eutectic phases. The eutectic phase played the most significant role in hardening.