采用Cube、Copper、S三种取向铝单晶(ASCs)在25～300 ℃、0.001～10 s 1条件下进行热模拟等温单轴压缩实验,获得三种取向ASCs在不同高温变形条件下的真应力-真应变曲线,建立其应变补偿高温变形本构方程以及热加工图.结果表明:不同晶体取向的ASCs的动态再结晶(DRX)程度存在显著差异,三种取向ASCs的DRX难度为:Cube＞Copper＞S.ASCs在等温单轴压缩过程中的流变应力随应变速率的减小与变形温度的升高而降低,各取向的最高流变应力水平为:Copper＞S＞Cube.各取向ASCs在变形过程中的微观组织演化耗能存在差异,其功率耗散率数值的大小顺序为:Cube＞Copper＞S.
Effect of Crystal Orientation on High Temperature Rheological Behavior of Aluminum Single Crystal
Thermal simulation isothermal uniaxial compression experiments were carried out with Cube,Copper and S oriented aluminum single crystaI(ASCs)at 25～300 ℃ and 0.001～10 s-1.The true stress-true strain curves of ASCs under different high temperature deformation conditions were obtained,and the strain compensation constitutive equation and thermal processing diagram were established.The results show that the degree of dynamic recrystallization(DRX)of ASCs with different crystal orientations is significantly different.The DRX difficulty of ASCs with three orientations is as follows:Cube＞Copper＞S.The flow stress of ASCs during isothermal uniaxial compression decreases with the decrease of strain rate and the increase of deformation temperature.The maximum flow stress level of each orientation is Copper＞S＞Cube.The microstructure evolution energy dissipation of ASCs with different orientations during deformation is different,and the order of the power dissipation rate is Cube＞Copper＞S.
crystal orientationaluminum single crystalhigh temperature rheological behaviorconstitutive equationhot working diagram
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