选择性激光熔化技术研究现状及发展趋势

选择性激光熔化技术是20世纪80年代发展起来的一种新型技术,应用该技术制备的零件致密度高、精度高、表面质量好、力学性能和化学性能优良。介绍了选择性激光熔化技术的原理和特点,概述了选择性激光熔化技术在生产设备和生产技术两方面的国内外发展现状。提出了选择性激光熔化设备的主要研究方向:激光器种类、聚焦面光斑尺寸大小、铺粉方式以及活塞缸铺粉厚度等。指出了改善金属粉末球化现象和裂纹孔隙的方法:通过改变激光发射器的功率和扫速率或对金属粉末进行预热处理的方法改善粉末球化现象;通过改变环境含氧量,扫描速率和铺粉厚度等可提高零件的致密度。针对设备生产速度慢、粉末综合性能存在缺陷和生产工业链不完善等方面的问题提出了对这项技术的发展建议。

Status and development trend of selective laser melting forming technology

Selective laser melting is a new technology developed in 1980s. The parts made by this technology have high density, high accuracy, good mechanical properties and chemical properties. The principle and characteristics of the selective laser melting technology is introduced, and the development status of the technology in production equipment and production technology at home and abroad is summarized. The main research directions of selective laser melting equipment are as follows: the laser type, the size of focusing spot, the way of laying powder, powder thickness and so on. The methods of improving the spheroidization of metal powder and crack pore are put forward: changing the power and sweep rate of the laser emitter or preheating the metal powder can improve the powder spheroidization; changing the environmental oxygen content, scanning rate and powder thickness can increase the density of parts. On the this basis of which, some constructive suggestions about slow production rate of equipment, and defects in powder performance and imperfect production chain are put forward.