摘  要：搅拌摩擦焊是一种新型绿色环保的焊接技术，适用于铝合金的连接，具有高效节能、变形小的特点。5083铝合金具有良好的力学性能、优良的耐腐蚀性能，被广泛的应用于各个领域。本实验对1mm厚5083-H111态铝合金薄板进行了搅拌摩擦焊对接试验，对各种参数条件的焊接接头进行组织观察和性能测试，通过金相显微镜、全自动维氏硬度计、万能拉伸试验机和场发射扫描电子显微镜对其显微组织、力学性能和断口形貌进行了观察测试和分析。结果表明：当焊接转速达到10000r/min以上时，可以实现1mm5083-H111薄板铝合金的对接焊接，当主轴转速一定时，随着焊接速度的增加，接头抗拉强度先增大后减小；焊接速度一定时，随着主轴转速的增加，抗拉强度也呈现先增大后减小的趋势。在主轴转速11000 r/min，焊速350 mm/min参数下进行焊接时，焊缝成形美观，焊接接头的拉伸性能较好，抗拉强度为331.04 MPa，延伸率17.8%，抗拉强度达到母材的100.3%。断裂发生在前进侧的热机影响区。焊核区组织为细小的等轴晶，焊接接头硬度分布基本呈倒“V”型分布，处于前进侧的区域硬度值稍比后退侧区域硬度值低，处于焊核区的硬度比热影响区硬度值高。

关键词：薄板；5083铝合金；搅拌摩擦焊；组织与性能；高转速

Abstract：Friction stir welding is a new type of green welding technology, suitable for aluminum alloy connection, with energy efficient, small deformation characteristics. 5083 aluminum alloy has good mechanical properties, excellent corrosion resistance, is widely used in various fields. In this experiment, the aluminum alloy sheet of 1mm thick 5083-H111 was subjected to friction stir welding test, and the welding joint was tested and tested on various parameters. Through the metallographic microscope, automatic Vickers hardness tester, Tensile test machine and field emission scanning electron microscopy were used to observe and analyze the microstructure, mechanical properties and fracture morphology of the microstructure. The results show that when the welding speed reaches 10000r / min or more, the butt welding of 1mm5083-H111 aluminum alloy can be realized. When the speed of the spindle is constant, the tensile strength of the joint increases first and then decreases with the increase of welding speed. When the speed is constant, with the increase of the spindle speed, the tensile strength also increases first and then decreases. When the welding speed is 11000 r / min and the welding speed is 350 mm / min, the tensile performance of the welded joint is good, the tensile strength is 331.04 MPa, the elongation is 17.8%, the tensile strength reaches the parent 100.3% of the material. The rupture occurs in the heat engine affected area on the front side. The hardness of the welded joint is basically "V" type distribution, the hardness value of the area on the front side is slightly lower than that of the back side, and the hardness of the weld zone is lower than that of the heat affected zone High hardness value.

Key words: sheet; 5083 aluminum alloy; friction stir welding; microstructure and properties; high speed.

目  录

第一章 绪论 1

1.1搅拌摩擦焊的简介 1

1.1.1搅拌摩擦焊的原理 1

1.1.2搅拌摩擦焊的工艺特点 1

1.1.3搅拌摩擦焊研究现状及应用 2

1.2 5083铝合金搅拌摩擦焊工艺 3

1.3薄板铝合金 3

1.3.1 薄板铝合金的搅拌摩擦焊 3

1.3.2薄板铝合金的研究现状 4

1.4研究意义和内容 5

1.4.1本课题的研究目的及意义 5

1.4.2本课题的研究内容 5

第二章 实验设备、材料设计及方案 7

2.1搅拌摩擦焊机 7

2.2实验材料的选择及准备 7

2.3搅拌摩擦焊搅拌头尺寸 8

2.4实验方案 9

2.4.1焊前准备 10

2.4.2焊接工艺参数的选择 10