[Back]

G. Liedl, M. Mayr, K. Whitmore:
"Laser assisted joining of aluminum-copper";
Keynote Lecture: International Conference on Photonics Research (Interphotonics 2018), Antalya (invited); 2018-10-08 - 2018-10-12.

The increasing industrial demand for components made of different materials is leading to an ever-growing interest in laser-assisted joining processes. Tailor-made components made of various materials can help to reduce weight and minimize resource consumption without affecting important component properties such as strength or reliability. Aluminum and copper, for exam-ple, are of great importance for electrical applications such as accumulators or lightweight electrical drives. Rising raw material prices make aluminum increasingly attractive compared to copper, since aluminum combines comparatively good thermal and electrical properties with a lower price and a mass density of about one third of copper. A major limitation in the use of alumi-num as a substitute for copper is the lack of reliable aluminum-copper joining processes. Complex interactions between these different materials and their different thermomechanical properties make thermal joining a challenge and can lead to joint failures even during the cooling phase. This paper deals with the laser welding of aluminum-copper samples in an overlapping configu-ration. The resulting joints were examined by optical microscopy, SEM and EDX analysis. Very tight intermetallic composite layers of Al-Cu could be achieved without cracks. Within the strength-relevant transition area of the joint there were only very few pores. Intermetallic compounds were identified in which the very hard, copper-rich compound with a thickness of less than 1 µm could be detected.

laser welding, IMC