Investigation of the coatings for hybrid high pressure die-casting of Al cast-steel sheet componentsThursday (09.11.2017) 09:35 - 09:55 Part of:
The hybrid lightweight construction is of great interest in the modern automotive industry. The combination of steel and aluminum components for weight reduction plays a particularly important role. As a result, the research of suitable manufacturing technologies for joining these materials is essential, especially in the field of car body construction. In addition to processes such as welding and brazing, die casting is an innovative method for the production of aluminum/steel sheet hybrid components. Since the cooling rate during die casting is many times higher than in most other processes, it is considerably more difficult to achieve a metallurgical bonding between aluminum melt and steel sheet. Therefore, in order to enhance the material closure different coating systems can be applied to the steel sheets.
The main goal of the current study is to understand the bonding mechanisms for aluminum/steel sheet joints during the die casting process and to investigate the influencing factors. In order to control the type of bonding at the interface between aluminum melt and steel and to analyze its influence on the formation of intermetallic phases and on a possible gap formation between the Al melt and the steel plate, coatings of Cu, Ni and Al-based alloys are applied to the steel sheet by means of thermal spraying. Of particular interest is the analysis of these layers with respect to the microstructural development of the contact zone between the steel substrate and coating and between coating and aluminum cast. The melting temperature and the tendency to oxidation of the coatings were analyzed by means of differential scanning calorimetry, since both properties represent important criteria for a metallurgical bond. First casting trials showed that partial melting of Al-based coatings during high pressure die casting allows achieving a metallurgical bonding between coating and aluminum melt.
|Category||Short file description||File description||File Size|
|Short Paper||This is a short manuscript to the abstract||223 KB||Download|