搅拌摩擦加工5083-O铝合金的组织和性能

发布时间：2018-03-18 06:47

本文选题：铝合金　切入点：搅拌摩擦加工　出处：《稀有金属》2017年09期 　论文类型：期刊论文

【摘要】：在不同的搅拌头轴肩直径、旋转速度及行进速度下,对2.7 mm厚5083-O铝合金薄板进行了搅拌摩擦加工处理(FSP)。研究表明,材料在搅拌摩擦加工过程中发生动态再结晶,加工区晶粒得到明显的细化。随着搅拌头的轴肩直径和旋转速度的增加,加工区晶粒尺寸逐渐增大;随着行进速度的增加,晶粒尺寸减小。通过搅拌摩擦加工处理,加工区性能得到改善。当采用大轴肩直径(16 mm)低行进速度时,加工区抗拉强度最低,与母材相当。随着搅拌头轴肩直径和旋转速度的减小,加工区抗拉强度上升,最高强度可达母材的108%,延伸率约为母材的123%。此外,研究了加工区内部明暗弧纹的形成机制和其性能差异。分析表明,与内部浅色弧纹区域相比,深色弧纹区域晶粒尺寸更小,Mg原子含量更高,位错更多,硬度也更高,其内部硬度差异随热输入量的增加而减小,大热输入量有利于提高加工区组织和性能的均匀性。
[Abstract]:Under the conditions of different shaft-shoulder diameter, rotation speed and travel speed of the stirring head, the friction stir treatment was carried out on the 27mm thick 5083-O aluminum alloy sheet. The results showed that the dynamic recrystallization of the material occurred during the friction stirring process. The grain size of the processing zone increases with the increase of the shaft shoulder diameter and rotation speed of the agitator, and decreases with the increase of the traveling speed. The properties of the processing zone are improved. When the large shaft shoulder diameter is adopted at a low speed of 16 mm, the processing zone has the lowest tensile strength, which is comparable to the base metal. With the decrease of the shaft shoulder diameter and rotating speed of the mixing head, the tensile strength of the processing zone increases. The maximum strength can reach 108% of the base metal, and the elongation is about 1233% of the base metal. In addition, the formation mechanism and performance difference of the bright and dark arc stripes in the processing zone are studied. The grain size of dark arc grain is smaller and mg atom content is higher, dislocation is more and hardness is higher. The difference of internal hardness decreases with the increase of heat input, and large heat input is helpful to improve the homogeneity of microstructure and properties of processing zone.
【作者单位】：东北大学材料科学与工程学院;
【基金】：国家自然科学基金重点项目(51334006) 国家“十二五”航空基金项目(61901110301)资助
【分类号】：TG146.21;TG306

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