This paper presents the results of investigating an Al-Fin bond between an aluminum piston alloy and austenitic cast iron. The part investigated utilized an austenitic cast iron insert for the first ring groove for application in a highly loaded diesel engine for increased wear resistance. A metallographic investigation using an optical microscope in combination with SEM/EDS (Scanning Electron Microscopy/Energy Dispersive Spectroscopy) analysis and 3D visualization of the quality of the intermetallic bonding layer was performed. The test results show that a metallic bond can be formed between the aluminum piston alloy and the austenitic cast iron.