Realization of Al/High Strength Steel: Joints by Ultrasound Supported Friction Stir Welding - Process and Robustness, Mechanical Properties using Destructive and Non-Destructive Testing Methods, Microstructure, Corrosion, and Joining Area Integrated Corro

到目前为止，该项目的重点是成功开发和构建了一种全新的混合焊接工艺，即超声辅助搅拌摩擦焊接（UA-FSW）。结果表明，FSW工艺一方面非常适合制造不同材料之间的材料复合材料，即使熔点差异很大；另一方面，与FSW工艺平行的功率超声传输如预期的那样改善了所生产的FSW接头的单调和循环性能。近年来，FSW工艺技术和工业应用材料领域都有了重要的发展。带有固定肩和旋转销的新型FSW工具使焊接具有不同熔点的材料成为可能，而且FSW工具不会出现不允许的磨损。此外，高强度钢越来越多地被用于汽车技术，作为轻量化结构的组成部分。然而，试图通过传统的FSW生产具有足够强度的Al /高强钢接头并不成功。在这种情况下，UA-FSW再次成为一种开创性的连接工艺，因为额外的超声波可以使材料之间的连接更加紧密，而不会增加连接区域的温度或fsw工具的更高磨损。因此，Al /高强钢接头应在第三阶段采用UA-FSW生产。除破坏性检测方法外，还提供了预处理、在线和后处理无损检测方法。此外，还将分析生产接头的微观结构，并研究不同接头的腐蚀行为，特别关注综合腐蚀防护概念。使用热成像方法来优化连接过程已经证明了自己，并将继续。在前两个资助期SPP1640自己的项目和其他项目中考虑的al轻质材料EN-AW 6061和EN-AC 48000将被重复使用。作为马氏体条件下硼化调质钢22MnB5的高强度连接伙伴，DP600和MS-W 1200在工业应用中越来越有意义。并将结果与第二次建国时期低强度钢C45和DC04的铝合金接头进行了比较。

The successful development and the construction of a completely new hybrid welding process, the Ultrasound Assisted Friction Stir Welding (UA-FSW), was in focus of the project, until now. It was found that the FSW process on the one hand is very suitable to produce material composites between dissimilar materials, even with very different melting points, and on the other hand that the parallel to the FSW process transmitted power ultrasound improves the monotonic and cyclic properties of the produced FSW-joints as expected. In recent years important developments in the FSW process technology as well as in the field of materials used in industrial application occur. New FSW tools with fixed shoulder and rotating pin make it possible to weld materials with very different melting points without an impermissibly wear of the FSW-tool. Furthermore, high-strength steels are increasingly being used in vehicle technology as elements of lightweight structures. However, attempts to produce Al / highstrength steel-joints by conventional FSW with sufficient strength were not successful. In this case, UA-FSW again is a pioneering joining process because the additional ultrasound can enable a more intensive joint between the materials without an increase of the temperature in the joining area or a higher wear of the FSW-tool. Therefore, Al / high-strength steel-joints should be produced in the third period by UA-FSW. Beside destructive testing methods, preprocess, in-line, and post-process non-destructive testing methods are provided. In addition, the microstructure of the produced joints will be analyzed and the corrosion behavior of the dissimilar joints will be investigated with a special focus on integrated corrosion protection concepts. The use of thermographic methods to optimize the joining process has proven itself and will be continued. The Al-lightweight materials EN-AW 6061 and EN-AC 48000 considered in the own project and other projects of the SPP1640 during the first two funding periods will be reused. As high strength steel joining partners boronalloyed tempered steel 22MnB5 in the martensitic condition, DP600 and MS-W 1200 should be considered, which are gaining more and more significance in industrial applications. Furthermore, the results will be compared with the joints between Al-alloys and the low strength steels C45 and DC04 of the second founding period.