Functionally Graded Materials: Continuous Casting and Forming of Electric Copper Conductors

在过去的几十年里，技术产品的电气化程度明显上升。结合对长寿命和高性能的需求，单片金属结构的潜力在很大程度上已经耗尽。因此，出现了重要的学术和工业活动，重点关注混合材料结构在电气应用中的使用。不仅制造混合材料本身是一个具有挑战性的问题。它需要对材料特性演变和技术关系的跨过程理解。本项目提案旨在研究电铜导体制造的工艺路线。特别是，该项目侧重于功能分级铜材料的开发，其特点是适应当地的冶金行为，针对电气应用的特定要求进行了优化。铜导体具有优良的导电性和较高的强度，采用初铸、后挤压、最后拉丝的工艺路线，是一种经济的生产流程。这种复杂的性质特征是由金属产品横截面上的材料梯度产生的。产品外部区域的纯铜基材与内部区域的铜锌合金材料之间的过渡是连续的。在研究项目的框架内，开发了一种资源高效制造功能梯度材料的方法。科学的方法是基于理论、实验和数值技术。目标具有挑战性，所产生的结果改变了目前技术可能性的局限性。

A rising electrification of technical products was apparent during the last decades. In combination with the demand for a long lifetime and high performance, the potentials of monolithic metallic structures are largely exhausted. Therefore, important academic and industrial activities arose, which focus on the usage of hybrid material structures for electric applications. Not only the fabrication of hybrid materials itself is a challenging issue. It requires a cross-process understanding of material properties evolution and technological relationships. The present project proposal aims at the investigation of the process route for the fabrication of electric copper conductors. In particular, the project focuses on the development of functionally graded copper materials, which feature locally adapted metallurgical behavior optimized for the specific requirements of electrical applications. The process route of initial continuous casting, subsequent extrusion and final wire drawing represents an economic production sequence for the fabrication of copper conductors, which exhibit an excellent electrical conductivity on the one hand and a comparatively high strength on the other hand. This complex properties character is generated by a material gradient over the cross-section of the metallic product. The transition between the pure copper base material in the outer region and copper zinc alloyed material in the inner area of the product is continuous. Within the framework of the research project, a methodology is developed for the resource-efficient fabrication of functionally graded materials. The scientific approach is based on theoretical, experimental and numerical techniques. The objectives are challenging and the results generated shift the present limitations of the technical possibilities.