中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 35 No. 11 November 2025 |
（1. School of Materials Science and Engineering, North University of China, Taiyuan 030051, China;
2. Institute of Special Metal Materials and Equipment, North University of China, Taiyuan 030051, China;
3. School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China;
4. Advanced Manufacturing and Intelligent Equipment Industrial Research Institute, Hai’an & Taiyuan University of Technology, Hai’an 226600, China;
5. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:A combination of casting and laser remelting was employed to develop a high-strength and heat-resistant Al-Si-Fe alloy suitable for powder bed fusion using a laser beam (PBF-LB). By clarifying the effects of the incorporated elements and their contents on the microstructure and mechanical performance of Al-Si-Fe alloys, the composition was optimized as Al-11Si-2.5Fe-2Mn-1.2Ni-0.4Cr (in wt.%). The optimized alloy was subsequently validated using PBF-LB, which exhibited favorable machinability, achieving a density of 99.8%. The room-temperature tensile strength of the PBF-LB manufactured Al-Si-Fe alloy reached (512.76±3.26) MPa, with a yield strength of (337.79±2.36) MPa and an elongation of (2.98±0.07)%. The enhanced room-temperature mechanical properties could be mainly attributed to the combined effects of fine-grain strengthening, solid solution strengthening, and precipitation strengthening. At 300 °C, the high-temperature tensile strength of the developed alloy reached (222.47±6.41) MPa, with a yield strength of (164.25±11.40) MPa and an elongation of (8.88±0.33)%, outperforming those of existing alloys documented in the literature. The improved high-temperature mechanical performance was primarily provided by the three-dimensional network comprising cellular heat-resistant Al17(FeMnNiCr)4Si2 and α-Al(FeMn)Si phases.
Key words: Al-Si-Fe alloy; laser powder bed fusion; alloy composition optimization; heat-resistant phase; strengthening mechanism
