不同应变量对7A04铝合金包申格效应的影响

Effect of Strain Capacities on Bauschinger Effect of 7A04 Aluminum Alloy

7A04铝合金在微小预应变量后的塑性变形过程中将产生包申格效应。对7A04铝合金采用4种不同应变量进行了轴向拉-压循环试验。结果表明:7A04铝合金在拉-压和压-拉变形下都会产生包申格效应。当预应变量小于2.5%时,预压缩变形条件下的包申格效应较预拉伸变形条件下更明显;当预应变量大于2.5%时,出现与之相反的结果 ,预应变量从1%增加到4%的过程中,包申格效应呈先增后减的趋势;当预应变超过2.5%后,包申格效应变得不太明显。

7A04 aluminum alloy produces bauschinger effect in the process of plastic deformation which followed tiny pre-strain capacities.Axial direction tension-compression cycle test was processed in 7A04 aluminium alloy with 4 different strain capacities.It was concluded that 7A04 aluminum alloy generates Bauschinger effect in both tension-compression and compression-tension deformation.Bauschinger effect under pre-compression deformation is bigger than that under pre-tension deformation when the pre-strain is less than 2.5%.However,it generates the opposite results when the pre-strain is greater than 2.5%.The bauschinger effect for 7A04 aluminum alloy has a tendency to decrease after increasing first when the pre-strain increases from 1% to 4% in the process,and Bauschinger effect becomes less obvious when pre-strain is over 2.5%.