The laser powder bed fusion (LPBF) technique is used to manufacture complex and customised components by exploiting the unique advantages of two types of metal materials to meet specific performance requirements. A comprehensive overview of LPBF-processed dissimilar metal materials, a combination of different single metals or alloys, is developed. The microstructure in the fusion zone and the corresponding mechanical properties of LPBF-processed dissimilar metal materials are summarised. The influence of processing factors on the mechanism of defect formation, wetting properties and element diffusion behaviour at the interface between different materials and their typical cases are scientifically investigated in detail. Particular attention is paid to energy input, Marangoni convection and interfacial bonding behaviour. The underlying science of the metallurgical structure and properties of the LPBF-processed dissimilar metal materials is revealed. The build quality and efficiency could be further improved by designing machine structures and predicting the process–property relationship. This review provides a significant guide for expanding the industrial application of LPBF-processed dissimilar metal materials.

Titanium alloys exhibit exceptional properties that enable their widespread application. Additive manufacturing (AM) technologies offer significant advantages for titanium alloy components, including rapid prototyping, high forming accuracy, and enhanced performance. Consequently, substantial research and industrial applications have emerged in the field of titanium alloy AM. Nevertheless, a systematic comparison and synthesis of related studies remains lacking. This paper reviews four distinct categories of titanium alloy AM processes classified by energy source (laser, electron beam, electric arc, and compressed air-assisted). Each category is analyzed in detail, with comparative assessments of microstructures, performance, and applications. Secondly, the paper comprehensively discusses current and potential applications of titanium alloy AM across aerospace, medical, and industrial sectors while identifying critical research gaps for future development. Finally, the development of novel titanium alloys for AM, titanium alloy AM assisted by acoustic or magnetic fields, and 4D printing of functional titanium alloys are discussed.