摘要
采用缆式焊丝进行CO_2气体保护焊,利用焊接电弧多信息采集系统拍摄了缆式焊丝CO_2气体保护焊电弧形态图像;用数码相机拍摄无缺陷焊缝横截面照片.基于实验结果分析了缆式焊丝CO_2气体保护焊工艺机理.建立了缆式焊丝CO_2气体保护焊有限元模型,对该工艺下温度场、应力-应变场进行了数值模拟.结果表明,缆式焊丝CO_2气体保护焊具有束状电弧,其由多弧旋转耦合而成,热流密度更为集中;当缆式焊丝CO_2气体保护焊单位长度焊缝的热输入为单焊丝CO_2气体保护焊的2.9倍时,其熔深与熔宽分别为单丝CO_2气体保护焊的4倍和1.7倍;在相同焊接条件下,缆式焊丝CO_2气体保护焊热效率与埋弧焊相近,残余应力场分布与埋弧焊相似,但熔深大于埋弧焊,熔宽、热循环峰值温度、热影响区宽度均小于埋弧焊.焊缝横断面的计算结果与实验结果吻合较好,证明了所建热源模型的准确性.
Cable-type welding wire （CTWW） CO2 gas shielded arc welding, which uses CTWW as consumable electrode, is an innovative arc welding process with high quality, high efficiency and low consumption, thus having significant potential of wide application in industrial manufacturing. So far, however, there is lack of deep study on this new welding technology, hindering its promotion. In this paper, the process mechanism of CTWW CO2 gas shielded arc welding is studied through combining the experimental detection and numerical simulation. By using arc multi-information collection system, the characteristics of arc shape and behavior in CTWW CO2 gas shielded arc welding process is acquired. The photographs of weld without defect are obtained. Based on the test results, the mechanism of CTWW CO2 gas shielded arc welding is explained. A finite element analysis model suitable to CTWW CO2 gas shielded arc welding is developed to simulate the temperature and stress field distribution. The results show that, there exist a unique bunchy electric arc in CTWW COs gas shielded arc welding, which is formed through multi-arc rotating and coupling, leading to arc heat concentration; the calculated weld cross section agrees well with the experimental data, validating the accuracy of established heat source model. When the heat input for per unit length in CTWW COs gas shielded arc welding is 2.9 times more than that in single welding wire （SWW） CO2 gas shielded arc welding, the weld penetration and width are 4 times and 1.7 times of those in SWW CO2 gas shielded welding, respectively. Under the same welding condition, the new welding process has a similar heat efficiency to submerged arc welding （SAW）, but its weld penetration is greater, and its weld width, heat-affected zone width and peak temperature of thermal cycle are smaller. Besides, the residual stress field in CTWW CO2 gas shielded arc welding is close to that in SAW.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2012年第11期1299-1305,共7页
Acta Metallurgica Sinica
基金
国家自然科学基金青年基金项目51105182和51005106资助~~
关键词
高效焊接
缆式焊丝
气体保护焊
工艺机理
有限元分析
high efficiency welding, CTWW, gas shielded arc welding, process mechanism, finite element analysis
