Fe–Al/AlSi compound casting based on a targeted oxide removal

The compound casting technique is a promising approach to achieve a higher level of efficiency in technologically advanced components. This paper presents a compound material that is suitable for reinforcing an AlSi10Mg alloy. The main emphasis is on developing a manufacturing technology to create a robust material bond between a high strength insert and casting. Considering both the strength properties and coefficient of thermal expansion, it was found that Fe–Al 40 at% intermetallics offer excellent potential for reinforcing AlSi castings. Different pre-treatments for cleaning the insert surface were investigated in experimental studies based on an understanding of the impeding effect of oxide layers. This paper examines three of these methods chemical pre-treatment using a flux, optical pre-treatment using laser ablation, and a combination of these techniques. The last method was found to be particularly successful. A metallographic examination, CT and EDX analyses, but also three-point bending tests suggested that the combined treatment could provide a reproducible and satisfactorily robust bond between the Fe-Al insert and AlSi bulk material.