Multiple principal element alloys encompass the well-known high entropy alloys (HEA). The alloy system represents a new class of materials consisting of at least three alloying elements, each containing 5 to 35 at.%. Thus, this alloying concept differs fundamentally from conventional materials such as steel or nickel alloys. For this purpose, the alloying elements are specifically selected, the microstructures are adjusted in a single-phase and, in some cases, multi-phase manner. In particular, conflicting goals, such as the trade-off between strength and ductility in conventional steels, are overcome. However, in the last 20 years, the focus has been on material synthesis. With the increase in available material quantities, the focus is now on processing issues such as joining and welding processes. The weldability of HEAs has received very little attention so far. The experience with dissimilar metal welds is completely lacking but is essential for the application of these materials in combination with conventional materials. The present study presents comprehensive experimental results on the weldability of an equimolar CoCrFeMnNi-HEA in cold-rolled and heat-treated condition, which was joined by tungsten inert gas welding to an austenitic steel AISI 304. The mechanical properties of the dissimilar metal welds were characterized by cross-weld tensile samples, whereas the local deformation in the weld of the different welding zones was measured by digital image correlation. In accordance with the respective initial HEA condition (cold-rolled vs. heat-treated), the local strain behavior was divergent and influenced the global mechanical properties of both DMW types. Nonetheless, the experiments provided proof in principle of the weldability for dissimilar joints of the CoCrFeMnNi-HEA welded to conventional materials like austenitic stainless steels ensuring a corresponding capability for mechanical loading. This allows further considerations on the application of these innovative materials.

多主元素合金包括众所周知的高熵合金 (HEA)。该合金系统代表了一类新材料，由至少三种合金元素组成，每种合金元素含量为 5 至 35 at.%。因此，这种合金概念从根本上不同于钢或镍合金等传统材料。为此，专门选择合金元素，以单相方式调整微观结构，在某些情况下以多相方式调整微观结构。特别是，克服了相互冲突的目标，例如传统钢的强度和延展性之间的权衡。然而，在过去的 20 年里，焦点一直集中在材料合成上。随着可用材料数量的增加，现在的重点是连接和焊接工艺等加工问题。到目前为止，HEA 的可焊性还很少受到关注。完全缺乏异种金属焊接的经验，但对于这些材料与传统材料的结合应用至关重要。本研究展示了冷轧和热处理条件下等摩尔 CoCrFeMnNi-HEA 的可焊接性的综合实验结果，该材料通过钨极惰性气体保护焊连接到奥氏体钢 AISI 304。异种金属焊缝的机械性能为通过交叉焊缝拉伸样品进行表征，而不同焊接区域焊缝的局部变形则通过数字图像相关测量。根据各自的初始 HEA 条件（冷轧与热处理），局部应变行为有所不同，并影响两种 DMW 类型的整体机械性能。尽管如此，实验原则上证明了 CoCrFeMnNi-HEA 异种接头与奥氏体不锈钢等传统材料焊接的可焊性，确保了相应的机械载荷能力。这使得人们可以进一步考虑这些创新材料的应用。