52, 081408(2015)
激光与光电子学进展
Laser & Optoelectronics Progress
©2015《中国激光》杂志社
081408-1
激光熔覆层端部形貌三维重构模型
宋梦华 林 鑫 杨海欧 黄卫东
西北工业大学凝固技术国家重点实验室, 陕西 西安 710072
摘要 激光熔覆层端部形貌对于激光立体成形加工精度及稳定性具有重要影响。基于粉末累积原理,分析了激光熔
覆层端部的形成过程。构建了描述激光熔覆层端部三维形貌的分析模型。实验制备了单道激光熔覆层,应用激光共
聚焦显微镜观察了激光熔覆层始末端部的形貌特征,并测量了不同横/纵截面的轮廓。结果表明,激光熔覆层端部沿
扫描方向由外向内宽度/高度逐渐增加,经过约半个熔池的距离后,宽度达到熔覆层宽度保持不变,初始/末尾熔池外
的区域高度达到稳 态 保持不变,而内部区 域继续增加,两区域形 成交界线。越过初始/末尾 熔 池后,熔覆层横截面 达
到稳态。模型与实验结果在主要几何特 征上相符的很好,表明粉末积累是决定熔覆层端部形貌的基本机制,所构模
型为认识理解激光熔覆层端部形貌提供了基础。
关键词 激光光学; 材料; 激光立体成形; 熔覆层端部形貌; 粉末累积; 分析模型
中图分类号 TG456.7 文献标识码 A
doi: 10.3788/LOP52.081408
A Model of Constructing the End of Single-Track Laser Cladding Layer
Song Menghua Lin Xin Yang Hai′ou Huang Weidong
State Key Laboratory of Solidification Processing, Northwestern Polytechnical University,
Xi′an, Shaanxi 710072, China
Abstract The morphology of ends of single-track laser cladding layer has an important influence on the processing
precision and stability in laser solid forming. Based on the principle of powder accumulation, the formation process
of ends of single-track laser cladding layer is analyzed. An analytical model of constructing the ends is developed.
Some single-track laser cladding layers are prepared. By laser scanning confocal microscope, the ends of single-track
laser cladding layers are observed. And the profiles of a series of cross section along the scanning direction and
longitudinal section are measured. The result indicates that the width/height of the ends increase inward along the
scanning direction. Beyond the distance of the radius of molten pool, the width of the ends equal to the one of the
cladding layer and keep stable. Moreover, the height of the zone out of the initial/tail molten pool reaches stable while
the one in the initial/tail molten pool keeps increasing. Between those two zones, a boundary of broken line is formed.
Beyond the distance of the length of molten pool, the cross section of laser cladding layer reaches stable. The
constructed result shows good agreement with the experimental one in the main geometry characteristics, which
indicates the powder accumulation is the primary mechanism in determining the morphology of ends of single-track
laser cladding layer. The developed model provides a foundation to get insight into the morphology of ends of single-
track laser cladding layer.
Key words laser optics; materials; laser solid forming; morphology of ends of single-track laser cladding layer;
powder accumulation; analytical model
OCIS codes 140.3390; 160.3900; 220.4610
1 引 言
激光立体成形(LSF)是一种先进的数字化增材制造技术
[1]
,其结合了快速原型的自由实体成形与同步送
收稿日期: 2015-04-27; 收到修改稿日期: 2015-05-15; 网络出版日期: 2015-07-28
基金项目: 国家自然科学基金(51323008)、国家 973 计划(2011CB610402)、国家 863 计划(2013AA031103)、凝固技术国家重
点实验室自主研究课题(91-QZ-2014)
作者简介: 宋梦华(1983—),男,博士研究生,主要从事激光成形修复 2Cr13 不锈钢方面的研究。
E-mail: songmenghua@163.com
导师简介: 黄卫东(1956—),男,博士,教授,主要从事金属高性能增材制造技术(3D 打印)与凝固理论等方面的研究。
E-mail: huang@nwpu.edu.cn(通信联系人)