Additive manufacturing-based combinatorial approach to improve bonding strength and heat transfer performance in wrought-cast Al compound casting

•Interface between Al wrought and cast was improved by Al-Si-Zn layer.•DED-based combinatorial study was performed to find optimal composition.•The coating layer was applied to actual-scale motor housing.•The interfacial bonding strength was improved by the coating layer.•The reactive interfacial layer led to the uniform heat transfer.