摘要
针对定向能量沉积(DED)复杂曲面零件余量不均及台阶效应明显等问题,提出了考虑DED复杂曲面成形特点的中面动态配准技术,以优化后处理减材加工余量。首先根据扫描路径构建曲面零件最小外包络的截面线,用于在机检测毛坯点云;然后提取理论模型中面与测量毛坯中面点云,引入不同区域配准精度要求,利用动态加权迭代最近邻点算法实现加工余量优化,并通过两简单案例对算法可行性进行初步验证;最后,以离心叶轮叶片为复杂案例,分析所提余量优化方法的准确性,并与基于遗传算法的多配准精度要求的加工余量优化技术进行对比。结果表明,所提余量优化算法的配准精度及计算效率高,可用于DED制造复杂曲面类零件的余量快速优化。
Complex free-form parts manufactured by DED had problems of uneven allowance distributions and severe stair-case effects.In order to optimize allowances for subtractive post-machining,a dynamic point cloud registration method using the mid-surface points of the deposited and theoretical parts was proposed to optimize the machining allowances,which took into consideration characteristics of the DED parts.Firstly,the section line of the minimum outer envelope of deposited complex free-form parts was constructed according to the deposition scanning path,and was used for obtaining the point cloud of the on-machine measurement.Secondly,the mid-surface points of the deposited and theoretical parts were extracted,and an iterative closest point with dynamic weights considering the multi-region allowance requirements was proposed to optimize the machining allowances.The feasibility of the algorithm was verified by two simple cases.Finally,a free-form blade of a centrifugal impeller was selected as a complex case for allowance optimization.The proposed method was also compared with the method for multi-region allowance using genetic algorithm.The results show that the proposed allowance optimization method is more accurate and efficient for rapid optimization of machining allowances for DED manufactured complex curved parts.
作者
侯亮
郭敬
陈云
叶超
徐杨
邹佳豪
HOU Liang;GUO Jing;CHEN Yun;YE Chao;XU Yang;ZOU Jiahao(Department of Mechanical and Electric Engineering,Xiamen University,Xiamen,Fujian,361005)
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2022年第17期2098-2106,共9页
China Mechanical Engineering
基金
国家自然科学基金(51905461,51975495)
科技部创新方法专项(2020IM010100)。
关键词
定向能量沉积
余量优化
在机检测
动态配准
台阶效应
directed energy deposition(DED)
allowance optimization
on-machine measurement
dynamic registration
stair-case effect
