Thermal Analysis and Production of As-Cast Al 7075/6060 Bilayer Billets

Thomas Greß, Tim Mittler, Simon Schmid, Hui Chen, Noomane Ben Khalifa, Wolfram Volk

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


Load-adjusted, weight-optimized components can be fabricated by following a multi-material approach. Integrating the respective advantages of strength and corrosion resistance of Al 7075 and Al 6060 into a single structural component leads to a complex property profile. Compound casting offers a high potential in terms of process chain shortening, material efficiency and bonding quality. The present paper focuses on the production of aluminum bilayer billets by multi-step, discontinuous compound casting. Process conditions influencing the formation of a cohesive bond at the interface are investigated. A fundamental thermal analysis is conducted in order to fully characterize the casting alloys. A process window for metallurgical bonding of Al 7075 and Al 6060 can be defined using a combined approach of process parameters and thermophysical data. The primary bonding mechanism is found to be the epitaxial solidification which occurs through remelting and recrystallization of the substrate alloy. Here the dendrite coherence point constitutes a critical level of the near-interface substrate temperature in terms of forming a solid solution. Epitaxy, phase composition and intermetallic diffusion processes are analyzed using SEM–EDS.

Original languageEnglish
Pages (from-to)817-829
Number of pages13
JournalInternational Journal of Metalcasting
Issue number4
StatePublished - 1 Oct 2019


  • aluminum bimetal
  • bilayer billet
  • compound casting
  • dendrite coherence point
  • epitaxy
  • thermal analysis


Dive into the research topics of 'Thermal Analysis and Production of As-Cast Al 7075/6060 Bilayer Billets'. Together they form a unique fingerprint.

Cite this