多场调控金属激光增材制造研究现状与展望（特邀）

Abstract

Significance Laser additive manufacturing (LAM) technology uses a focused highenergy laser beam as the heat source to achieve integrated forming of complex metal components, avoiding the complex postprocessing steps of traditional processing techniques and achieving high forming efficiency, which makes it have broad application prospects in aerospace, automotive, medical and other fields. The metal additive manufacturing process based on laser and powder mainly includes two types: selective laser melting (SLM) and laser directed energy deposition (LDED). LAM has been widely used in the forming of various metal materials, including aluminum alloys, titanium alloys, copper alloys, nickelbased superalloys, magnesium alloys, steel, and so on.Due to the current widespread use of Gaussian laser in laser additive manufacturing technology, the peak intensity generated in the focusing area is very high. When laser interacts with metal powder, the widthtodepth ratio of the melt pool is small and there are large temperature gradient and cooling rate. The instability caused by complex melt flow dynamics and the accumulation of repeated heating and cooling cycles are prone to keyholes, splashing, spheroidization, residual stress, cracks, and anisotropic microstructures, which seriously affect the strength, toughness, and fatigue resistance of formed components in turn. Modifying the alloy composition 1002306 -23 特邀综述 第 51 卷 第 10 期/2024 年 5 月/中国激光 or adding strengthening phase particles can effectively eliminate the cracks and anisotropic columnar crystal structure in metal samples.