To obtain high-performance Al-Si-based cast alloys,refinement and modification of Si phases are required.An Al-12Si/ZnS powder inoculant was designed and fabricated using a chemical bath deposition method.The efficien...To obtain high-performance Al-Si-based cast alloys,refinement and modification of Si phases are required.An Al-12Si/ZnS powder inoculant was designed and fabricated using a chemical bath deposition method.The efficiency of the inoculant for modifying the eutectic Si phase in as-cast Al-12Si alloy was studied.Results show that Al-12Si/ZnS powder can significantly refine the eutectic Si in Al-Si cast alloys.The best refinement effect for eutectic Si is achieved with 17.5wt.%Al-12Si/ZnS powder.Coarse long needle-shaped eutectic Si with a length of 18μm was modified into approximately spherical shape with a diameter of 6.53μm,which is evenly distributed throughout the alloy.The E2EM model calculation indicates that the inter-plane misfit(F_(p))and inter-atomic spacing misfit(F_(r))between ZnS and Si are all less than 0.5%,which confirms that ZnS is a potential nucleation site for Si phase.The hardness,tensile strength,and elongation of Al-12Si alloys modified with 17.5%Al-12Si/ZnS powder increase 6.30%,16.18%and 55.45%,respectively,compared to the unmodified Al-12Si alloy.The fracture behavior of the alloy with 17.5wt.%Al-12Si/ZnS powder is dominated by transgranular fracture supplemented by intergranular fracture.展开更多
基金the financial support from the National Natural Science Foundation of China (Grant No. 51672145)
文摘To obtain high-performance Al-Si-based cast alloys,refinement and modification of Si phases are required.An Al-12Si/ZnS powder inoculant was designed and fabricated using a chemical bath deposition method.The efficiency of the inoculant for modifying the eutectic Si phase in as-cast Al-12Si alloy was studied.Results show that Al-12Si/ZnS powder can significantly refine the eutectic Si in Al-Si cast alloys.The best refinement effect for eutectic Si is achieved with 17.5wt.%Al-12Si/ZnS powder.Coarse long needle-shaped eutectic Si with a length of 18μm was modified into approximately spherical shape with a diameter of 6.53μm,which is evenly distributed throughout the alloy.The E2EM model calculation indicates that the inter-plane misfit(F_(p))and inter-atomic spacing misfit(F_(r))between ZnS and Si are all less than 0.5%,which confirms that ZnS is a potential nucleation site for Si phase.The hardness,tensile strength,and elongation of Al-12Si alloys modified with 17.5%Al-12Si/ZnS powder increase 6.30%,16.18%and 55.45%,respectively,compared to the unmodified Al-12Si alloy.The fracture behavior of the alloy with 17.5wt.%Al-12Si/ZnS powder is dominated by transgranular fracture supplemented by intergranular fracture.
