Abstract：Al-Ce-Sc-Zr alloy was performed by selective laser melting (SLM) using gas atomization Al-10Ce-0.4Sc-0.2Zr (mass fraction) pre-alloyed powders as raw materials. The effects of laser power and scanning speed on the relative density and mechanical properties of the alloy were studied by optical microscopy and room temperature tensile test to optimize the process parameters. X-ray diffractometer, scanning electron microscope and transmission electron microscope were also used to study the eutectic microstructure morphology, phase composition and grain size of the alloy prepared by SLM under the optimal process parameters. The results show that the relationship between laser power, scanning speed and the relative density, mechanical properties of the alloy are non-linear, with the increase of laser energy density, the relative density and mechanical properties of the alloy show a trend of increasing and then decreasing. The optimum parameters are laser power of 350 W and scanning speed of 2 000 mm/s. The relative density of Al-Ce-Sc-Zr alloy after process optimization can reach 99.92% with tensile strength of (441±3) MPa, yield strength of (370±18) MPa and elongation of (9.4±0.9)%. The as-built Al-Ce-Sc-Zr alloy presents a columnar-equiaxed bimodal grain structure. The grain orientation is relatively random, indicating that no strong texture is formed. The alloy consists of α-Al and Al11Ce3 phases. Sc and Zr atoms are mainly presented as the form of solid solution in α-Al matrix. The eutectic Al11Ce3 phase has an irregular ribbonlike morphology with an average width of 35 nm and is arranged in a complex discontinuous network. The eutectic microstructure is very fine and uniformly distributed.
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2023, Vol. 28 
