激光熔覆成形技术的研究进展

Research Progress of Laser Cladding Forming Technology

激光熔覆成形技术是近年来发展起来的一种新型的先进制造技术。该技术将激光熔覆表面强化技术和快速原型制造技术相结合,具有成形零件复杂、结构优化、组织性能优良、加工材料范围广泛、柔性化程度高、能实现梯度功能和无模近终成形等独特优点,可广泛应用于复杂零件的直接制造和修复,具有广阔的应用前景。介绍激光熔覆成形技术的原理、特点和应用,从几种典型激光熔覆成形系统、成形零件组织性能研究、温度场数值模拟、成形过程检测与控制和成形过程残余应力和裂纹产生的原因及对策等方面对激光熔覆成形技术的研究进展进行综述,指出该技术存在的问题,并对其发展方向进行预测和展望。激光熔覆成形技术在硬件系统、工艺研究和熔池检测与控制等方面都取得了可喜的进步,但成形精度和裂纹仍然是该技术领域非常棘手的问题,有待进一步突破。

Laser cladding forming（LCF） is a novel advanced manufacturing technology developed in recent years.It combines the technologies of laser cladding surface modification and rapid prototyping manufacturing,and has the characteristics such as capable of forming complex components with optimized structures and better microstructure and properties,wider applied category of processing materials,higher flexibility,capable of realizing gradient function manufacturing and dieless near net shaping.Therefore,it can be widely used in the manufacturing and repairing of complex components and has an extensive application prospect.The principle,characteristics and application of laser cladding forming are introduced.The research progress of laser cladding forming are reviewed and commented from aspects of several typical laser cladding forming systems,microstructure and properties of formed components,numerical simulation of the temperature fields,measurement and control of the forming process,the generation reasons and countermeasures for residual stress and cracking,and so on.The problems existing in this technology are proposed and the development direction of this technology is prospected and predicted.In laser cladding forming technology,gratifying progresses is made in hardware systems,processes,melting pool detection and control,etc.However,forming precision and cracking are still the very thorny problems yet to be further broken through.