激光粉末床熔融成形Al-Si-Fe-Mn-Ni-Sc-Zr合金的组织形貌及腐蚀行为OA

To investigate the effects of adding different mass fractions of Al-Mg-Sc-Zr alloys on the microstructure and corrosion behavior of Al-Si alloy formed by powder bed fusion-laser beam(PBF-LB),10％,20％,and 30％mass fractions of Al-Mg-Sc-Zr powders were added to the Al-Si-Fe-Mn-Ni(ASF)alloy powder.The ASF-M cross-over alloy was fabricated through powder bed fusion-laser beam technology,and the microstructure and corrosion resistance of the ASF-M alloy were compared and analyzed.The results show that adding an appropriate amount of Al-Mg-Sc-Zr alloy can effectively inhibit the growth of grains in the equiaxed zone and columnar zone of the ASF-M alloy,refine the α-Al grains and Si network structure in the equiaxed zone,and reduce the size of Si particles in the columnar zone(10～100 nm).The electrochemical test results show that the ASF-M10 alloy exhibits higher impedance,lower corrosion current density,and superior pitting resistance compared to the ASF-M0 alloy;while the corrosion resistance of the ASF-M20 and ASF-M30 alloys is slightly lower than that of the ASF-M0 alloy.The analysis of immersion corrosion morphology indicates that with the addition of Al-Mg-Sc-Zr alloy,the interlayer corrosion of the continuous layer of ASF-M alloy is inhibited,and a few pitting corrosion pits appear;this is mainly because the refined Si reticular structure can effectively inhibit galvanic corrosion,and at the same time,the Mg element can play a role in stabilizing the oxide film.