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Due to its low density, high strength, and stiffness the intermetallic phase Al 3 Ti is a good candidate as reinforcement for Al alloys. In this work, in situ Al 3 Ti particle reinforced Al composites are fabricated from Ti particles and Al melt via melt stirring with a high shearing mixer. Microstructure and mechanical properties are investigated. The results indicate that, owing to the high shearing effect and intensive macroscopic flow of the melt, reinforced particles are distributed homogeneously on the microscopic and macroscopic scale. Furthermore, Al 3 Ti particles are proved to be effective nuclei for heterogeneous nucleation of α-Al, thus the grain size of the Al matrix is significantly decreased. As a result of the fine grains and the uniform distribution of Al 3 Ti particles, E-modulus, yield, and tensile strength of the composites are enhanced.

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Aluminum–aluminum compound castings consisting of an aluminum wrought alloy sheet and an aluminum casting alloy are produced via high pressure die casting (HPDC). In order to realize a firm bonding, the sheet material is Zn‐coated prior to casting. The task of the Zn‐coating is to replace the resistant aluminum oxide layer on the surface. In addition, a smooth metal–metal interface between the insert and the casting alloy develops by the diffusion of Zn atoms into the surrounding area of the interface. Within this paper, the subsequent heat treatment of the resultant formation is investigated to enhance the strength of the firmly bonded compound. In a first step, heat treatment for two wrought alloys AlZn5.5MgCu, AlCu4MgSi, and the casting alloy AlSi10Mg(Fe) are examined. Based on these results, suitable parameters for the heat treatment of the compounds are selected and tested. Mechanical tests demonstrate a significant enhancement for the strength of the heat treated compounds. Microprobe analysis is used to examine the diffusion and dissolution of the coated Zn at the boundary layer during the solution annealing of the firmly bonded compound.