高性能金属构件的激光增材制造
摘要
Laser additive manufacturing is an integrated manufacturing technology that takes precision forming and high performance into consideration. Laser additive manufacturing includes the laser solid forming technique, which is characterized by synchronized powder feeding, and selective laser melting, which is characterized by powder bed fusion. The microstructure of metal components produced by laser additive manufacturing technology consists of columnar dendrite that is epitaxially grown from the substrate. The grains in the metal components are coarse; however, the microstructure in the grains is fine, without the macro segregation. As a result, the mechanical properties of the components produced by laser additive manufacturing technology are equivalent to the forging standard. Laser additive manufacturing technology can also be combined with traditional processing technology to achieve combination manufacturing for the production of complex and high-precision components. In the present paper, recent developments in laser additive manufacturing technology have been reviewed in the following aspects: technical principles, microstructure characteristics, mechanical properties, and application status. On this basis, this paper discusses the development trends in the field and the key scienti c issues to be solved. It is noted that the optimized structural design of metal components based on functional priority has become possible.