【作者】 姜涛；

【导师】 许光明；

【作者基本信息】 东北大学 ， 材料加工工程， 2017， 硕士

【摘要】 6xxx铝合金由于具有较高的强度、良好的成形性、时效硬化性、散热性能好、耐腐蚀等特点,是汽车材料轻量化的理想选择。本文通过铸轧制备6181铝合金板坯,并冷轧至成品厚度,在此基础上研究了固溶和时效处理工艺制度对铝合金组织性能的影响,并根据6181铝合金板材烤漆硬化性确定6181铝合金热处理工艺制度。论文取得以下研究结果:(1)在6181铝合金组织中,除了 α-Al和Mg2Si相外,还存在AlSi相。经540℃/30min的固溶处理后,AlSi相基本融入基体,而Mg2Si相有残存。(2)随着预时效温度的升高,合金内析出AlSi相所需要的时间缩短。当预时效温度为190℃,时效时间为10min时,合金内的AlSi相的析出达到最大。(3)通过6181铝合金人工时效研究表明,在进行180℃人工时效48h内,合金内析出相变化不大,48h后AlSi相开始析出,且随时效时间的延长,AlSi相析出量增大,96h达到最大。(4)通过预时效后的板材进行180℃/30min的烤漆处理研究发现,合金内的相析出量没有出现明显的变化。(5)采用预时效和烤漆热处理工艺时,预时效制度为150℃/3min时,合金的抗拉强度达到最大值312.7MPa;预时效制度为190℃/7min时,合金的屈服强度达到最大值305.6MPa;而采用人工时效处理6181铝合金板材时,人工时效180℃/4h时,合金的抗拉强度及屈服强度分别达到最大值374.7MPa与370.2MPa。更多还原

【Abstract】 6xxx aluminum alloy become the ideal choice for lightweight automotive materials for its high strength,good formability,well heat dissipation,corrosion resistance,and so onIn this paper 6181 aluminum alloy slabs were cast by twin-roll casting and then cold rolled to the final products.The effects of solid solution and aging treatment on the microstructure and properties of aluminum alloy were studied.The heat treatment process of 6181 aluminum alloy was determined according to baking hardening.This paper has obtained the following results:(1)In the 6181 aluminum alloy,the AlSi phase was existed except for the α-Al and Mg2Si phases.After the solution treatment at 540℃/30min,the AlSi phase is basically integrated into the matrix,while the Mg2Si phase has a amount of residual.(2)With the increase of the pre-aging temperature,the time for precipitation of the AlSi phase was shortened.The precipitation of AlSi phase in the alloy reaches the maximum when the pre-aging is 190℃/10min.(3)During the artificial aging,the AlSi phase began to precipitate after 48h and reached the maximum at 96h.(4)It was found that the amount of phase precipitated in the alloy did not change significantly after the pre-aging sheet was baked at 180℃/30min.(5)With the pre-aging and baking treatment process,when the pre-aging system is 150℃/3min,the tensile strength of the alloy reaches a maximum of 312.7MPa.When the pre-aging system is 190℃/7min,the yield strength of the alloy reaches the maximum value of 305.6MPa.When the artificial aging is 180℃/4h,the tensile strength and yield strength of the alloy reach the maximum value of 374.7MPa and 370.2MPa更多还原