基于高速CCD摄像的短路过渡焊接熔滴检测与分析  

Detect and analysis of molten droplet in short-circuit arc welding based on high-speed charge coupled device camera

作　　者：朱志明[1] 吴文楷[1] 陈强[1] 

机构地区：[1]清华大学机械工程系,北京100084

出　　处：《焊接学报》2006年第3期29-33,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(59975050)

摘　　要：建立了基于高速CCD摄像的熔滴图像检测和焊接电流、电弧电压同步采集系统，在给出短路过渡模式下的熔滴尺寸定义并简述基于MATLAB平台的熔滴尺寸与电弧信号分析系统的基础上，对平特性电源短路过渡CO2焊接熔滴尺寸变化特征及其与工艺性能间的关系进行了试验研究。结果表明，熔滴尺寸呈分散性较大的止态分布（1～2倍焊丝直径），过大或过小的熔滴尺寸均不利于短路过渡焊接过程的稳定性。根据熔滴的形成和过渡过程，初步分析了影响熔滴尺寸的主要凼素及控制熔滴尺寸的途径，即短路过程结束后焊丝端部的残余液态金属量和燃弧能量的随机性导致丁熔滴尺寸的不确定性，对其进行有效控制将提高熔滴尺寸和短路过渡过程的一致性，进而改善短路过渡CO2焊接的工艺性能和焊接质量。An experimental system to photograph molten droplet images by using a high-speed charge coupled device camera and to record welding current and arc voltage in phase was established.After the definition of molten droplet size in short-circuit transfer mode was given and the analysis system for molten droplet size and arc signals based on MATLAB platform was introduced,the characteristic of molten droplet size in short-circuit CO_2 arc welding using the power supply with constant voltage output,the relationship between the molten droplet size and the welding process behavior were investigated.The experimental results show that the molten droplet size presents normal distribution between 1 and 2 times of wire electrode diameter.The excessive large or small size in molten droplet are all unfavorable to the stability of welding process in short-circuit transfer mode.According to the formation and transfer course of molten droplet,the main influence factors to the molten droplet size are analyzed and the approaches to control the droplet size are proposed.Namely,the random characteristic of the residual liquid metal quantity at the end of wire electrode after the completion of short-circuit transfer and the arc energy induces the uncertainty of molten droplet size.(making effective control on them will increase the accordance of molten droplet size and short-circuit transfer procedure,and improve the process behavior and welding quality of short-circuit CO_2 arc welding further.)

关 键 词：高速CCD 熔滴尺寸 短路过渡 随机性 

分 类 号：TG403[金属学及工艺—焊接]