激光熔覆成形金属零件中微裂纹的减少和消除

REDUCING AND ELIMINATING THE MICRO-CRACKS IN THE METAL COMPONENTS FORMED BY LASER CLADDING

激光熔覆成形技术是近年来发展起来的一种新的快速原型制造技术,该技术将快速原型制造技术和激光熔覆表面强化技术相结合,既保留了快速原型制造技术中能够快速制造复杂零件的特点,又具有成形零件性能优良、组织结构致密的优点,是快速原型制造技术中一个重要的发展方向。激光熔覆成形技术的一个亟待解决的问题是成形零件中的微裂纹问题,通过理论分析激光熔覆成形技术和激光熔覆表面强化技术之间的区别,找到了减少和消除激光熔覆成形金属零件中产生微裂纹的一个突破点,这就是激光熔覆成形中的基体材料。对多种基体材料及其预热温度和多种合金粉末材料进行了试验研究,重点研究基体材料对激光熔覆成形零件过程中微裂纹的影响,获得了激光熔覆成形的金属试样。通过理论分析和试验研究,得出以下结论:在适当选择基体材料及其预热温度和合金粉末的条件下,完全能够减少和消除激光熔覆成形过程中产生的微裂纹。

The laser cladding form is a new rapid prototyping technology. It combines the rapid prototyping with the laser cladding. It has the advantages of both rapid prototyping and laser cladding. The components formed by laser cladding possess the characteristics of complex shapes and excellent compositions. The micro-cracks produced in laser cladding form is a very important problem to be solved. The differences between laser cladding form and laser cladding are analyzed and the breakthrough point to reduce and eliminate the micro cracks is found. It is the substrate material. The influence on micro-cracks of different substrate materials is experimentally researched and the experimental samples are obtained. The conclusion that in the conditions of selecting propriety substrate material, propriety preheating temperature and propriety alloy powder can be obtained, the micro-cracks produced in laser cladding form can completely be reduced and eliminated.