The influence of Mg content on the microstructures and mechanical properties at room temperatures of A1-3.5Cu- （0.71-1.81）Mg alloys was studied. Precipitation phases in the alloys were identified by TEM and HRTEM. T...The influence of Mg content on the microstructures and mechanical properties at room temperatures of A1-3.5Cu- （0.71-1.81）Mg alloys was studied. Precipitation phases in the alloys were identified by TEM and HRTEM. The results show that when Mg contents increase from 0.71 to 1.81 wt%, the precipitates are transformed from S, S＂, 2, and 0 phases to S and St phases, and f2 phase is first observed in A1-3.48Cu-0.71 Mg alloy with Cu/Mg mass ratio of 5 during the conventional aging heat treatment （190 C/12 h）. Regard to aging hardness effect of the tested alloys, the hardness of the alloys improves with the increase of Mg content, but the increases become slow when Mg content is greater than 1.35 wt%.展开更多
The effects of Cr and Cr/Mn combined additions on the semi-solid microstructure of wrought Al-Mg-Si alloys are investigated.In the Cr-added alloy,the Al-7Cr compound is formed with homogeneously distributed in theα-A...The effects of Cr and Cr/Mn combined additions on the semi-solid microstructure of wrought Al-Mg-Si alloys are investigated.In the Cr-added alloy,the Al-7Cr compound is formed with homogeneously distributed in theα-Al matrix after homogenization.Both of the Al-7Cr andα-Al-（12）Mn3-Si-2 dispersiod particles are found in the homogenized microstructure of the Cr/Mn-added alloy.In the semi-solid microstructures,the smallestα-Al grains are obtained in the 60% cold-rolled alloys.After prolonged holding time,theα-Al grain size of the Cr/Mn-added alloy is smaller than that of the Cr-added alloy.Heavy deformation by cold-rolling accelerates spheroidization of theα-Al grains.The D-SSF process is found to be useful to modify the microstructures of both the Cr-added and Cr/Mn-added Al-Mg-Si alloys.展开更多
The effect of solution heat treatment （SHT） on mechanical properties, microstructure and surface quality of Al-1.2Mg-0.6Si-0.2Cu-0.6Zn alloy was investigated by tensile test, Erichsen test, surface topography, scann...The effect of solution heat treatment （SHT） on mechanical properties, microstructure and surface quality of Al-1.2Mg-0.6Si-0.2Cu-0.6Zn alloy was investigated by tensile test, Erichsen test, surface topography, scanning electron microscope （SEM） and electron back-scattered diffraction （EBSD）. The results indicate that with the increase in SHT temperature, yield strength and cupping test value （IE） of the sheets increase greatly and reach a peak value, then decrease. Meanwhile, intermetallic com- pounds dissolve into matrix gradually. The grains grow up as SHT temperature increases, and abnormal grain growth leads to the surface defects after solution-treated above 560 ~C. Considering mechanical properties, IE value, residual phases, grain size and surface quality of the sheets, SHT temperature for the alloy should not be higher than 550 ℃.展开更多
This article fully discusses the basic principle of on-line quenching for aluminum alloy extrusion and process conditions to realize on-line quenching,lists on-line quenching parameters for partly common aluminum allo...This article fully discusses the basic principle of on-line quenching for aluminum alloy extrusion and process conditions to realize on-line quenching,lists on-line quenching parameters for partly common aluminum alloy extrusion,indicates chemical composition of aluminum alloy;billet quality and homogenizing treatment;pre-heating condition of billet before extrusion;quenching sensitivity of alloy and cooling speed of extrusion on-line quenching;Advanced precision water-mist-gas quenching device is a necessary and sufficient condition to realize this process.It is an advanced and effective process which can simplify process flow,improve production efficiency,shorten production period,reduce production cost and has important economic value.展开更多
基金financially supported by the National Basic Research Program of China(Nos.2012CB619500 and 2010CB731700)the National Natural Science Foundation of China(No.51375503)
文摘The influence of Mg content on the microstructures and mechanical properties at room temperatures of A1-3.5Cu- （0.71-1.81）Mg alloys was studied. Precipitation phases in the alloys were identified by TEM and HRTEM. The results show that when Mg contents increase from 0.71 to 1.81 wt%, the precipitates are transformed from S, S＂, 2, and 0 phases to S and St phases, and f2 phase is first observed in A1-3.48Cu-0.71 Mg alloy with Cu/Mg mass ratio of 5 during the conventional aging heat treatment （190 C/12 h）. Regard to aging hardness effect of the tested alloys, the hardness of the alloys improves with the increase of Mg content, but the increases become slow when Mg content is greater than 1.35 wt%.
文摘The effects of Cr and Cr/Mn combined additions on the semi-solid microstructure of wrought Al-Mg-Si alloys are investigated.In the Cr-added alloy,the Al-7Cr compound is formed with homogeneously distributed in theα-Al matrix after homogenization.Both of the Al-7Cr andα-Al-（12）Mn3-Si-2 dispersiod particles are found in the homogenized microstructure of the Cr/Mn-added alloy.In the semi-solid microstructures,the smallestα-Al grains are obtained in the 60% cold-rolled alloys.After prolonged holding time,theα-Al grain size of the Cr/Mn-added alloy is smaller than that of the Cr-added alloy.Heavy deformation by cold-rolling accelerates spheroidization of theα-Al grains.The D-SSF process is found to be useful to modify the microstructures of both the Cr-added and Cr/Mn-added Al-Mg-Si alloys.
基金supported by the National Program on Key Basic Research Project of China(No. 2012CB619504)the National Natural Science Foundation of China(No.51271037)
文摘The effect of solution heat treatment （SHT） on mechanical properties, microstructure and surface quality of Al-1.2Mg-0.6Si-0.2Cu-0.6Zn alloy was investigated by tensile test, Erichsen test, surface topography, scanning electron microscope （SEM） and electron back-scattered diffraction （EBSD）. The results indicate that with the increase in SHT temperature, yield strength and cupping test value （IE） of the sheets increase greatly and reach a peak value, then decrease. Meanwhile, intermetallic com- pounds dissolve into matrix gradually. The grains grow up as SHT temperature increases, and abnormal grain growth leads to the surface defects after solution-treated above 560 ~C. Considering mechanical properties, IE value, residual phases, grain size and surface quality of the sheets, SHT temperature for the alloy should not be higher than 550 ℃.
文摘This article fully discusses the basic principle of on-line quenching for aluminum alloy extrusion and process conditions to realize on-line quenching,lists on-line quenching parameters for partly common aluminum alloy extrusion,indicates chemical composition of aluminum alloy;billet quality and homogenizing treatment;pre-heating condition of billet before extrusion;quenching sensitivity of alloy and cooling speed of extrusion on-line quenching;Advanced precision water-mist-gas quenching device is a necessary and sufficient condition to realize this process.It is an advanced and effective process which can simplify process flow,improve production efficiency,shorten production period,reduce production cost and has important economic value.
