Microstructure And Properties Of Two-melts Cast Al-Mg-Si Alloys Subsequent To Plastically Deformed

Xinjiang is a major energy province and a major exporter of electricity.It undertakes the important task of "transmitting electricity from west to east" and has played an important role in ensuring the safety of the nation's power supply.In order to effectively reduce the electrical losses of power transmission,higher requirements are placed on aluminum alloy cables.In this paper,Al-Mg-Si alloy and Al-Mg-Si-Y alloy were prepared by two-melts casting(TMC)method,and Al-Mg-Si alloy was prepared by traditional casting method.The microstructure and mechanical and electrical properties of the as-cast alloy,as well as the homogenized treatment,extruded state and solution aging state were compared.Provide methods and references for further research on aluminum alloy materials.The Al-Mg-Si alloy prepared by double-melt casting and traditional casting method,using metallurgical microscope(OM)to observe the as-cast structure analysis shows that the as-cast structure is mainly composed of ?-Al,the grain shape is equiaxed,the crystal The grain size is not uniform.Unresolved non-equilibrium eutectic structure and impurity phases are found around the grain boundaries.The grains are relatively complete,but the segregation is serious.For the Al-Mg-Si alloy prepared by the two casting methods,a resistance furnace was used to homogenize at 380? for different times,and the effect of homogenization time on the mechanical and electrical properties of the alloy was analyzed.Use a micro-hardness tester to test the microhardness of the alloy.The hardness shows a downward trend at lh-4h,and the hardness shows an upward trend at 4h-5h.An electronic universal test tensile machine is used to test the tensile strength of the alloy and the resistance of the alloy at lh-3h.The tensile strength shows an upward trend and the elongation rate shows a downward trend.The tensile strength of the 3h-5h alloy shows a downward trend and the elongation rate shows an upward trend.The conductivity is tested by the Seebeck conductivity tester,and the electrical conductivity of the 1h-3h alloy increases After 3h,the conductivity began to decline.By extruding the Al-Mg-Si alloy prepared by the two casting methods,the alloy structure has changed significantly.The equiaxed grains in the as-cast state are extruded into long fibrous shapes by external forces,and the grain boundaries become Obviously,there are a small amount of black second particles.The extruded alloy was subjected to solution aging treatment at different times using a resistance furnace,and the effect of aging time on the mechanical and electrical properties of the alloy was studied.Artificial aging lh-5h microhardness increased,5h-9h showed a downward trend;in lh-5h tensile strength showed an upward trend,elongation showed a downward trend,5h-9h tensile strength decreased,elongation increased;lh-5h conductance The rate rises and the conductivity decreases from 5h-9h.