Recent research progress on additive manufacturing of high-strength low-alloy steels: Focusing on the processing parameters, microstructures and properties

Owing to the excellent weldability, high strength and toughness, etc., high-strength low-alloy (HSLA) steels are widely used in pipelines, ships and railways. In the past years, increasing research is focusing on unfolding the efficient manufacturing methods to achieve the desired structures with high performance for HSLA steels. Ad-ditive manufacturing (AM), as a disruptive manufacturing technique with large freedom of material selection, can realize the fabrication of complex objects with upgraded properties by using a layer-by-layer forming manner. Therefore, currently many research efforts have been spent on integrating the AM techniques with HSLA steels, and the trend is continuously expanding. This paper provides a timely review regarding the research status of HSLA steels in additive manufacturing field, from the aspects of forming characteristics, processing param-eters, microstructure evolution, mechanical and corrosion properties, aiming to assisting the construction of the relationship among manufacturing parameters, microstructure and properties. Finally, the future research challenges and opportunities are also forecasted. Hopefully, this paper could promote the development of HSLA steels related research and applications.