基于激光铣削的光内输送微纳粉激光熔覆复合精确成形技术研究

项目名称： 基于激光铣削的光内输送微纳粉激光熔覆复合精确成形技术研究

项目编号： No.51205266

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 机械工程学科

项目作者： 王明娣

作者单位： 苏州大学

项目金额： 25万元

中文摘要： 激光熔覆成形高性能薄壁金属零件时，由于熔覆层凹凸不平和挂渣导致成形件表面精度差甚至后续成形困难，往往需要在成形过程中或成形后辅助机械铣削加工和抛光处理。但是成形件因急冷凝固，表面硬度很高，加工非常困难；形状复杂的零件机械加工更需多次装夹，加工时间长，有时要占整个制造周期的60% 以上。为此本申请提出一种基于激光铣削的光内输送微纳粉激光熔覆复合精确快速成形的新技术，拟采用微纳粉作为激光熔覆用粉体，提高粉体对激光的吸收性能，从而可以用光斑更小、光束质量更好的激光成形薄壁件；采用高速CCD实时观测反馈激光熔覆过程中熔覆层的宏观形貌，通过激光振镜三维铣削实现熔覆层精度的闭环控制；从而实现薄壁金属零件的精确成形。该方案克服了传统激光熔覆成形件表面精度低的现状，避免了可能需要的机械精整加工，缩短了加工时间，降低了加工成本，不仅可用于高性能薄壁件的精确成形，也可用于高附加值"废弃"零件的修复和再制造。

中文关键词： 激光熔覆；激光铣削；复合精确成形；闭环控制；实验研究

英文摘要： The forming of thin-walled parts by laser cladding results in the development of uneven cladding layers that manifests itself in poor surfaces. Furthermore, it makes it difficult for follow-up forming. In this case, it becomes necessary to conduct auxiliary mechanical milling and polishing. However, laser forming is one quench solidification process that results in high hardness which makes machining of these hardened surfaces impractical. In addition, If the shape of part is complex, the finishing machining operations will require multiple jigs and fixtures setups which are time consuming and highly inefficient, In fact, the finishing machining operations could account for more than 60% of the entire manufacturing cycle. To overcome these difficulties, a new composite precision rapid prototyping technology is proposed. This new technology is based on laser cladding by feeding a mixture of micro-nano powders in hollow laser beam and machining the resulting part by laser milling. The micro-nano powder used in laser cladding will improve the absorption performance of the powder, leading to greatly improved of laser beam. This will allow us to use high-speed CCD to detect and feedback the macroscopic morphology of the cladded layer. The newly proposed high performance and precise approach will result in greatly imp

英文关键词： laser cladding；laser milling；composite precision forming；close-loop control；experiment study