磁感应强度-分级压差对ZL114A合金中共晶Si形貌和性能的影响  

Effects of the Magnetic Intensity and Stepwise Pressurization on Silicon Morpholog and Properties for ZL114A Alloy

作　　者：周泽远 芦刚 陈义斯 曾扬帆 李勇 徐翩 严青松 Zhou Zeyuan;Lu Gang;Chen Yisi;Zeng Yangfan;Li Yong;Xu Pian;Yan Qingsong(National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology,Nanchang Hangkong University)

机构地区：[1]南昌航空大学轻合金加工科学与技术国防重点学科实验室

出　　处：《特种铸造及有色合金》2023年第12期1674-1679,共6页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(52265051)。

摘　　要：在真空差压铸造过程施加交变磁场以强化复杂薄壁铝合金铸件的力学性能,研究了磁场-压力协同场对ZL114A合金共晶Si形貌和力学性能的影响。结果表明,交变磁场能有效破碎粗大块状共晶Si,在合金基体中形成细小纤维状组织,同时破碎的Si相受压力场挤滤渗流影响进一步细化,共晶Si长宽比随着分级加压压差增大而减小。随着磁感应强度增加,合金的抗拉强度和伸长率先增大后减小,而分级压差增大,铸件抗拉强度增大,但伸长率先增大后减小。压差为135 kPa,磁感应强度为24 mT,此时铸件的抗拉强度为302.67 MPa,伸长率为3.8%。磁感应强度为24 mT,分级加压压差提升至160 kPa,协同场处理的ZL114A合金抗拉强度达312.31 MPa,相较于60 kPa低压差协同场下合金性能,提升了约59.31%。The mechanical properties of complex thin-walled aluminum alloy castings were strengthened by applying the alternating magnetic field during vacuum counter-pressure casting process.The effects of alternating magnetic-pressure synergistic field on morphology of eutectic silicon and mechanical properties of ZL114A alloy were systematically analyzed.The results indicate that the alternating magnetic field can effectively break the coarse bulk eutectic silicon and form a fine fibrous structure in the alloy matrix.Meanwhile,the broken silicon phase is further refined due to the squeeze infiltration effects of the pressure field.Thus,the aspect ratio of eutectic silicon is decreased with the increase of the pressure difference.Additionaly,the tensile strength and elongation of the alloy are increased firstly and then decreased with the increase of the magnetic field strength.However,the tensile strength of the castings is increased with the increase of the stepwise pressurization pressure,while the elongation is increased firstly and then decreased.With magnetic field strength of 24 mT and the pressure difference of 135 kPa,the tensile strength of the casting reaches 302.67 MPa with the elongation of 3.8%.The tensile strength of ZL114A alloy samples treated by the synergistic field reaches the maximum value of 312.31 MPa under the magnetic at 24 mT with the stepwise pressurization of 160 kPa,which is about 59.31%higher than that of one under the low pressurization of 60 kPa.

关 键 词：交变磁场 分级压差 力学性能 共晶Si 

分 类 号：TG249.2[金属学及工艺—铸造] TG146.21[一般工业技术—材料科学与工程]