Research on an SVM Prediction of Welding Deformation Rectification for High-Strength Steel Fillet-Welded Joints after Traveling Induction Heating

Abstract

To effectively realize the welding deformation rectification of high-strength steel fillet-welded joints in hull construction, a traveling induction coil was used to research the rectification effect of the welding deformation, and the support vector machine (SVM) method was applied to study the ability to predict the rectification amount. Welding and induction heating experiments were carried out on the fillet-welded joints, and finite element models, which were used to expand the prediction sample library of the SVM model, were established according to the experimental process. Then, the induction current, frequency, moving rate of the induction coil, weld deformation amount, and sheet thickness were selected as the input characteristic parameters of the SVM model to predict the rectification results achieved by traveling induction heating. It can be concluded that the established finite element model can accurately simulate the continuous machining process of welding-induction heating in reality, the induction heating method can actively eliminate welding deformation, and the SVM algorithm based on the radial basis function can predict the rectification result of weld deformation with high precision. The welding process of fillet-welded joints is one of the most common basic construction process units in shipbuilding, and the welding deformation caused by thermal elastoplastic deformation directly threatens the structural strength of hull construction (Liang et al. 2015; Yi et al. 2020). Extensive results indicate that welding deformation and welding residual stress are the main causes of hull structure deformation and stress corrosion; therefore, how to effectively realize the welding deformation rectification of fillet-welded joints has become a research topic of interest (Zhou & Wang 2019). At present, the flame heating method is the preferred method used to rectify a welding deformation; however, some disadvantages in the flame heating method, which include temperature control difficulties, poor automation, harsh construction environments, and ease of material property damage, can seriously affect the quality and strength of a hull structure (Kotani et al. 2016; Kalyankar & Shah 2018). In contrast, electromagnetic induction heating technology, which has a high degree of controllability, environmental friendliness, high heating efficiency, and low dependence on worker experience, has attracted the attention of researchers (Barclay et al. 2013; Haglund & Kristoffersen 2014).