基于双向拉伸的热环境铝合金性能获取和分析

Acquisition and analysis of aluminum alloy property in thermal environment based on biaxial tension

板材成形加工时通常承受复杂载荷,一般采用单拉试验获取材料性能,由于材料变形时仅承受单向载荷,与实际情况差距较大。为获取更加真实的复杂加载时材料性能,通过十字形试件双向拉伸试验,研究了热环境双向变比例加载时AA6016铝合金材料力学性能和变形行为,包括优化设计十字形试件、相关试验方法和设备以及结果分析等。在25、150和250℃温度下进行了拉伸速率比例为1∶1、3∶2、2∶3、1∶3和3∶1的双向拉伸试验和单向拉伸试验,得到了不同拉伸速率比例和温度下的应力应变关系、屈服规律和各向异性,建立了屈服准则,并且通过与试验结果对比,讨论分析了几个典型屈服准则及其适用性。

When sheet metal is forming,it usually bears complex loads.However,uniaxial tension test is usually used to obtain material properties,because the material only bears unidirectional load when deforming,which is far from the actual situation.In order to obtain more real material properties under complex loading,mechanical properties and deformation behavior of AA6016 aluminum alloy material under different stretching rates in thermal environment were studied using biaxial tensile test,including optimized design of cruciform specimen,relevant test method and equipment,analysis of test results,etc.The biaxial tensile tests and uniaxial tensile test were carried out under different temperatures of 25℃,150℃and 250℃and different stretching rate of 1∶1,3∶2,2∶3,1∶3 and 3∶1.The stress-strain relationship,yield criterion and anisotropy at different tension rate ratios and different temperatures were obtained.Further by comparison with the test results,the several typic yield criteria and their suitability were discussed.