The most important issues in the joining of similar aluminum alloy are softening of weld zone and reduction in tensile strength of joints. Use of a metallic interlayer can resolve these issues. In the present research work, effect of brass interlayer on the properties of friction stir welded 6061-T6 aluminum alloy was studied. X-ray diffraction analysis was carried out to investigate the phase composition with brass interlayer. Al₂Cu and Al₄Cu₉ intermetallic compounds were formed at the welded zone. Mechanical properties were examined through the tensile and microhardness testing. Tensile test results reveal that the use of brass interlayer is a good solution to improve the joint strength, as the insertion of brass interlayer enhances the joint strength up to 36%. In addition, use of brass interlayer enhances the microhardness at the weld zone and the softening issue has been resolved to some extent. Field emission scanning electron microscopy was used to investigate the mechanism of fracture behavior in fractured tensile specimens. However, insertion of brass interlayer slightly changes the ductile fracture toward brittle fracture.

在类似铝合金的连接中，最重要的问题是焊接区的软化和接头抗拉强度的降低。使用金属夹层可以解决这些问题。在本研究工作中，研究了黄铜夹层对搅拌摩擦焊接6061-T6铝合金性能的影响。进行了X射线衍射分析以研究黄铜夹层的相组成。Al ₂ Cu和Al ₄ Cu ₉金属间化合物在焊接区形成。通过拉伸和显微硬度测试来检查机械性能。拉伸测试结果表明，使用黄铜夹层是提高接头强度的良好解决方案，因为插入黄铜夹层可将接头强度提高多达36％。另外，黄铜夹层的使用增强了焊接区的显微硬度，软化问题已得到一定程度的解决。场发射扫描电子显微镜用于研究断裂拉伸试样的断裂行为机理。但是，插入黄铜夹层会使韧性断裂向脆性断裂稍加改变。