焊接电流作用下熔池形状特征与熔透状态的关系

Relationship between weld pool shape features and penetration state at different currents

熔池形状特征在一定程度上能表征熔透状态。建立了基于GMAW的视觉传感打底焊试验系统,基于熔池图像特点开发图像处理算法,提取熔池面积与长宽比参数。在其他工艺参数保持不变的情况下,改变焊接电流开展打底焊试验,分析焊接电流不同时熔池面积与长宽比的变化规律,探索这2个形状特征参数与熔透状态的对应关系。试验结果表明,随着焊接电流的增大,熔池面积及长宽比增大,二者变化趋势一致。当熔池面积与长宽比分别处于一定的数值范围内时,打底焊缝熔透良好。任何一个参数小于上述数值范围,会出现未熔透;大于上述数值范围,将出现焊漏现象。该结论可为熔透控制研究提供基础数据。

The shape features of weld pool could be used to characterize the penetration state to some extent. A visual sensing test system for backing welding of GMAW was established,and an image processing algorithm was developed based on the characteristics of weld pool images to extract parameters of the pool area and length-width ratio. Backing welding tests were carried out with changing current under the condition that other parameters remain unchanged. The variations of the weld pool area and length-width ratio with current were analyzed,and the relationships between the two shape parameters and the penetration state were discussed. The test results showed that the pool area and length-width ratio increased with the welding current,and the change trends of the two parameters basically kept consistent. The backing weld penetration was good when each parameter of the pool area and lengthwidth ratio was in a certain range,any parameter less than the given range indicated partial penetration,and that greater than the given range indicated partial welding leakage. The above work provided basic data for the study of penetration control.