时效处理对6061-T6铝合金板组织和力学性能的影响

Effects of Aging Treatment on Microstructure and Mechanical Properties of 6061-T6 Aluminum Alloy Plates

通过采用拉伸试验、扫描电镜和光学显微镜等试验方法,研究了时效处理对6061-T6铝合金板力学性能和组织的影响。结果表明:时效温度过低或时效时间较少,合金弥散强化效果减弱;而时效温度过高或时效时间过长,析出的晶粒尺寸变大。随着时效温度的升高,抗拉强度先增大后减小,时效温度为190℃时铝合金的抗拉强度最大为336MPa,时效温度为150℃,时效时间为2 h,铝合金最大断后伸长率为21.47%。6061-T6铝合金的硬度受时效温度的影响较大,受时效时间的影响较小,在时效温度为170℃、时效时间为2 h时达到最大硬度114.2 HV。拉伸断口分析表明随着时效温度和时效时间的增加,韧窝的数量变少且深度变浅,材料的塑性较差。

The effects of aging treatment on the mechanical properties and microstructure of 6061-T6 aluminum alloy plates were investigated by using experimental methods such as tensile tests,scanning electron microscopy and optical microscopy.The results show that,the aging temperature is too low or the aging time is too short,the dispersion strengthening effect of the alloy is weakened,while the aging temperature is too high or too long,the precipitated grain size becomes larger.With the increase of aging temperature,the tensile strength increase first and then decrease,and the maximum tensile strength of the aluminum alloy is 336 MPa at aging temperature of 190℃.The maximum elongation after break is 21.47%at aging temperature of 150℃and aging time of 2 h.The hardness of 6061-T6 aluminum alloy is influenced by aging temperature,but less by aging time,and reaches the maximum hardness of 114.2 HV at aging temperature of 170℃and aging time of 2 h.The maximum hardness of 114.2 HV is achieved at an aging temperature of 170℃and an aging time of 2 h.The tensile fracture analysis shows that with the increase of aging temperature and aging time,the number of tough nests becomes less and the depth becomes shallower,and the plasticity of the material is poor.