• Stemper, Lukas

Abstract

Innovations in the field of electric mobility have recently led to intensified efforts in the research and development of light-weight solutions in the automotive industry. AlSiMg-cast alloys, which are commonly used for structural cast components like chassis carrier or strut support, seem to have reached the end of their optimization potential and need to be replaced by an improved alloy system with regard to future challenges. In addition to intense literature review this work includes a characterization of five precipitation-hardenable AlMg-wrought alloys, which were processed by high pressure die casting. This thesis also focuses on the development of suitable heat treatments in order to achieve the mechanical properties required for structural components in the future. Two of three zinc-containing alloys were able to achieve higher yield strength than 250 MPa and even reached 325 MPa in the best case. While the elongation at fracture of these systems did not meet expectations with a maximum of 5 %, fracture elongations of up to 15 % were possible for the zinc-free, copper-containing alloys. However, the strength target was not achieved as the maximum yield strength didn’t exceed 215 MPa. Although the intended pairing of high yield strength and elongation could not be reached in this first attempt, the results nevertheless seem to imply a high potential of this approach. Further investigations are necessary to improve this alloy concept and make it attractive for future structural components in automotive industry.

Topics

• mobility
• zinc
• strength
• copper
• precipitation
• yield strength
• die casting