2001 年 19 巻 4 号 p. 628-633
In the present work, a three-dimensional (3-D), non-stationary thermal model for MAG (Metal Active Gas) welding is developed. The transient temperature distribution on the base metal is numerically analyzed in order to estimate the molten pool size by using a finite difference model based on the heat flow equation, and the theoretical configuration of molten pool is calculated, taking account of the balance of gravity, surface tension and arc pressure. The developed model can be applied to various welding processes such as multi-pass welding, lap welding and welding with torch weaving. To evaluate the validity of the model analysis, the calculated results are compared with the experimental results in MAG welding. Good correspondence is demonstrated between experiment and calculation. Accordingly, it is concluded that the model is capable of predicting MAG arc welding process.