The effects of solution-ageing treatment on the mechanical properties of semi-solid metal(SSM)products were studied by the method of orthogonal experiment.The microstructure and tensile properties at different treatme...The effects of solution-ageing treatment on the mechanical properties of semi-solid metal(SSM)products were studied by the method of orthogonal experiment.The microstructure and tensile properties at different treatment conditions were analyzed.The results show that the effects of solution-ageing treatment were obviously influenced by the original microstructure of the SSM billet. Higher temperature is favorable for the sufficient solution of alloy elements,but the grains will grow up when treated at a higher temperature or soaked for a longer time.There is a contradiction between the maximum tensile strength and elongation percentage. Under the condition of solution treatment at 475℃for 12 h and at 133℃for 20-22 h ageing,better properties including about 540 MPa of tensile strength and more than 6.3%of elongation can be obtained in general.The surplus phases not melted in the substrate and the solution precipitated supersaturated elements are the main factors influencing the properties of the alloys.展开更多
To explore the influence of double liquid quenching on the cutting performance of the 7A09 aluminum alloy,quasi-static compression and dynamic impact tests were carried out on the 7A09 aluminum alloy after double liqu...To explore the influence of double liquid quenching on the cutting performance of the 7A09 aluminum alloy,quasi-static compression and dynamic impact tests were carried out on the 7A09 aluminum alloy after double liquid quenching using an MTS810.23 universal testing machine and split-Hopkinson pressure bar(SHPB).The experimental data were fitted to obtain the Johnson–Cook constitutive model parameters of the alloy.Simulations of the machining process were carried out using the Deform-3D finite element software.The results showed that the rheological stress increased with the increase in strain rate and the decrease in temperature.The increase in the cutting speed and feed caused the cutting temperature to rise sharply,whereas the influence of the cutting amount on the cutting temperature was weak.Because of the presence of chip nodules,there was extremum in the cutting force vs cutting speed curves.The increase in the feed and cutting depth increased the cutting area Ac,so the cutting force also increased.The simulation results were verified by experiments.The simulation predictions were in good agreement with the test values,and the cutting force and temperature variations with the cutting parameters were the same.Thus,the correctness of the 7A09 aluminum alloy finite element model was verified.展开更多
基金Project(2007-837)supported by Science and Technology Program of Weihai,China。
文摘The effects of solution-ageing treatment on the mechanical properties of semi-solid metal(SSM)products were studied by the method of orthogonal experiment.The microstructure and tensile properties at different treatment conditions were analyzed.The results show that the effects of solution-ageing treatment were obviously influenced by the original microstructure of the SSM billet. Higher temperature is favorable for the sufficient solution of alloy elements,but the grains will grow up when treated at a higher temperature or soaked for a longer time.There is a contradiction between the maximum tensile strength and elongation percentage. Under the condition of solution treatment at 475℃for 12 h and at 133℃for 20-22 h ageing,better properties including about 540 MPa of tensile strength and more than 6.3%of elongation can be obtained in general.The surplus phases not melted in the substrate and the solution precipitated supersaturated elements are the main factors influencing the properties of the alloys.
基金Projects(51575289,51705270)supported by the National Natural Science Foundation of ChinaProject(2019GHY112068)supported by the Key Research and Development of Shandong,China
文摘To explore the influence of double liquid quenching on the cutting performance of the 7A09 aluminum alloy,quasi-static compression and dynamic impact tests were carried out on the 7A09 aluminum alloy after double liquid quenching using an MTS810.23 universal testing machine and split-Hopkinson pressure bar(SHPB).The experimental data were fitted to obtain the Johnson–Cook constitutive model parameters of the alloy.Simulations of the machining process were carried out using the Deform-3D finite element software.The results showed that the rheological stress increased with the increase in strain rate and the decrease in temperature.The increase in the cutting speed and feed caused the cutting temperature to rise sharply,whereas the influence of the cutting amount on the cutting temperature was weak.Because of the presence of chip nodules,there was extremum in the cutting force vs cutting speed curves.The increase in the feed and cutting depth increased the cutting area Ac,so the cutting force also increased.The simulation results were verified by experiments.The simulation predictions were in good agreement with the test values,and the cutting force and temperature variations with the cutting parameters were the same.Thus,the correctness of the 7A09 aluminum alloy finite element model was verified.
