| With the increasingly severe energy and environmental issues,the demand for lightweight vehicles has become more and more intense,and the application of high specific strength aluminum alloy sheets in the body has become an important development direction.Different panels or different parts of the same panel experience different stamping deformations.The effect of size and direction on the subsequent precipitation behavior of strengthening phase strengthening and the uniformity of mechanical properties of stampings remains to be studied.In this paper,6082 aluminum alloy sheet is taken as the research object.The W state cold stamping is used as the background to carry out the W state deformation experiment.The mechanical properties test combined with DSC,TEM,SEM,OM and other methods are used to explore the natural aging of the 6082 aluminum alloy by the W state deformation.Baking aging,mechanical properties after artificial aging and the effect of strengthening phase precipitation.The results show that the W state 0°,45°,90° direction deformation can inhibit the natural aging and improve the bake hardenability of the sample,and has little effect on the mechanical properties after artificial aging;the effect of different direction deformation on aging has different effects: The deformation in the direction of the direction significantly reduces the peak temperature and the precipitation activation energy of the precipitation strengthening phase,and the deformation reduction effect in the 45° direction is not obvious.The90°deformation can reduce the peak temperature of the precipitation strengthening phase,but has no effect on the precipitation activation energy.Combined with the solid solution hot stamping process,the high temperature deformation experiment was carried out to investigate the effect of high temperature deformation on the mechanical properties and strengthening phase precipitation of 6082 aluminum alloy after aging strengthening.The results show that the high temperature deformation in the 0° direction can inhibit the natural aging,which is not conducive to the baking aging,has little effect on the artificial aging,and increases the peak temperature and precipitation activation energy of the precipitated phase.The number of precipitated phases in the matrix after baking is small and the size is small.The high temperature deformation in the 45° direction inhibits the natural aging,slightly softensthe baking,has little effect on the artificial aging,reduces the peak temperature and the precipitation activation energy of the precipitated phase,and has a small decrease;the high temperature deformation in the 90° direction inhibits the natural aging,which is not conducive to baking.Aging and artificial aging.Different temperature pre-aging experiments were carried out to investigate the effect of pre-aging on the aging strengthening of the sheet.The results showed that pre-aging treatment at 140 ?,150?,160 ?,,170?,10 min can effectively inhibit the natural aging,and with the increase of temperature,The stronger the inhibition,the better the effect on baking aging,but the effect of 140 and 150? is more obvious.The pre-aging samples at 160 and 170? are over-aged in artificial aging.Pre-aging was applied after deformation in W temper and high temperature deformation,and the influence of pre-aging after deformation on aging strengthening was investigated.The results show that the pre-aging treatment of 0°,45° and 90°W-state deformation has a stronger effect on the inhibition of natural aging,baking aging and artificial aging than that in W-state deformation,and the peak-to-peak temperature of ?? phase is lowered.More obvious,but the activation energy can be increased;the pre-aging treatment after high temperature deformation in the 0°,45°,and90° directions has a stronger effect on the inhibition of natural aging,baking aging and artificial aging than the simple high temperature deformation treatment. |
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