Development of a novel processing route for dispersoid/precipitation-strengthened high conductive copper alloys by using metallized nano ceramics in additive manufacturing

由于其优异的导热性和导电性，铜合金在工业应用或电迁移等方面发挥着重要作用。在激光增材制造中，低合金铜合金的高反射率和高导热性限制了其应用。提出的研究目标是开发新的高强度，高导电性的铜合金，为选择性激光熔化（SLM）工艺量身定制（使用红色和绿色激光）。通过将金属化陶瓷纳米颗粒与沉淀强化CuCrZr合金混合，引入强化相。采用考虑计算热力学（CALPHAD）的递归合金设计策略，通过气体雾化制备粉末，并通过电子显微镜（SEM， TEM， EDX， EBSD， FIB， APT）对粉末进行全面表征。同时，将金属化工艺应用于陶瓷纳米颗粒，在随后的激光熔化过程中建立均匀混合。伴随着工艺模拟，小型测试样品将通过系统地改变工艺参数和构建策略的SLM方法产生。根据各自的微观结构和机械/氧化性能，合金设计将相应地进行调整，最终实现功能和结构材料性能的最佳组合。

Due to their excellent thermal and electronic conductivity, Cu alloys play a fundamental role, e.g., in industrial applications or electro mobility. In laser-based additive manufacturing, the employment of low-alloy Cu alloys is limited by its high reflectivity and heat conductivity. Objective of the proposed research is the development of novel high-strength, high-conductive Cu alloys, tailor-made for selective laser melting (SLM) processes (using red and green laser light). Strengthening phases are introduced by means of mixing metallized ceramic nano-particles with a precipitation strengthened CuCrZr alloy. By using of a recursive alloys design strategy taking computational thermodynamics (CALPHAD) into account, powders will be produced by gas atomization and thoroughly characterized by electron microscopy methods (SEM, TEM, EDX, EBSD, FIB, APT). At the same time, a metallization process is applied to ceramic nano-particles to establish a homogeneous mixing during the subsequent laser melting process of the resulting MMCs. Accompanied by a process simulation, small test samples will be produced by means of SLM with systematically varying the process parameters and build strategies. According to the respective microstructure and mechanical/oxidation properties the alloy design will be adapted accordingly, to finally achieve an optimum combination between functional and structural material properties.