Metal Additive Manufacturing for Automotive Applications: Technologies, Materials, Industrial Uses, and Future Directions

Metal additive manufacturing (MAM) offers automotive manufacturers design and supply-chain options, but published demonstrations do not by themselves establish production readiness or economic advantage. This critical narrative review connects process selection, alloy behaviour, component requirements and the complete manufacturing chain. It covers laser powder bed fusion, directed energy deposition, binder jetting and metal material extrusion, distinguishing direct vehicle parts from tooling, repair and spare parts. The synthesis identifies the following three recurring constraints: fatigue performance cannot be inferred from tensile strength; sintering-based routes require control of shrinkage and local defects; and printing productivity must be separated from output of accepted finished parts. Published examples include a 10% piston mass reduction and a 17% moulding-cycle reduction, both reported by industrial sources rather than established as sector-wide effects. A requirement-led selection framework, condition-specific material benchmarks and a qualitative economic assessment connect these findings to engineering decisions. The strongest opportunities occur where functional integration, avoided tooling or asset-life extension offset qualification and post-processing costs. Evidence remains heterogeneous and the initial single-database search limits coverage; the review therefore does not claim a systematic census or a universal ranking of technologies. Adoption should be judged at the level of a qualified alloy–process–part combination against a credible conventional alternative.