激光熔覆多道搭接成形及粉末利用率  

Multi-channel lap forming and powder utilization ratio of laser cladding

作　　者：练国富 曹强 郑颖 冯美艳 LIAN Guo-fu;CAO Qiang;ZHENG Ying;FENG Mei-yan(School of Mechanical and Automotive Engineering,Fujian University of Technology,Fuzhou 350118,China)

机构地区：[1]福建工程学院机械与汽车工程学院,福建福州350118

出　　处：《材料热处理学报》2023年第2期127-139,共13页Transactions of Materials and Heat Treatment

基　　金：福建省2021年省级科技创新重点项目(2021G02009)。

摘　　要：针对曲面基体激光熔覆多道搭接成形质量及粉末有效利用率问题,采用响应面中心复合设计方法,构建工艺参数与响应输出之间的数学模型,分析工艺参数与多道搭接激光熔覆层平整度、稀释率和粉末利用率之间的影响关系,以获得多道搭接激光熔覆的最佳工艺参数。结果表明:平整度随着激光功率和气流量的增加而减小,随着扫描速度和搭接率的增加而增大;稀释率随着激光功率的增加而增大,随着扫描速度的增加先减小后增大,随着搭接率的增加而减小;粉末利用率随着激光功率的增加而增大,随着扫描速度和搭接率的增加而减小。以平整度大于0.75、稀释率为10%、粉末利用率最大为目标,并基于数学模型对工艺参数进行优化与预测,得到最佳工艺参数为激光功率为1.800 kW、扫描速度为7.000 mm/s、气流量为10.000 NL/min、搭接率为22.744%。以最佳工艺参数制备的熔覆层的平整度、稀释率和粉末利用率与模型预测结果的误差分别为4.645%、3.332%和6.140%,证明了模型多目标优化的准确性。Aiming at the problem of forming quality and effective utilization ratio of powder in multi-channel laser cladding on curved substrate,a mathematical model between process parameters and response output was established by using response surface center composite design method,and the relationship between process parameters and flatness,dilution ratio and powder utilization ratio of multi-channel laser cladding layer was analyzed to obtain the optimal process parameters of multi-channel laser cladding.The results show that the flatness decreases with the increase of laser power and gas flow,and increases with the increase of scanning speed and overlapping ratio;the dilution ratio increases with the increase of laser power,decreases first and then increases with the increase of scanning speed,and decreases with the increase of overlapping ratio;the powder utilization ratio increases with the increase of laser power,and decreases with the increase of scanning speed and overlapping ratio.Aiming at flatness greater than 0.75,dilution ratio of 10% and maximum powder utilization ratio,the process parameters are optimized and predicted based on the mathematical model,and the optimal process parameters are obtained as follows:laser power of 1.800 kW,scanning speed of 7.000 mm/s,gas flow rate of 10.000 NL/min and overlapping ratio of 22.744%.The errors between the flatness,dilution ratio and powder utilization ratio of the cladding layer prepared with the optimal process parameters and the predicted results of the model are 4.645%,3.332% and 6.140%,respectively,which proves the accuracy of the multi-objective optimization of the model.

关 键 词：激光熔覆 响应面 曲面基体 多道搭接 工艺参数 

分 类 号：TG174.44[金属学及工艺—金属表面处理]