1988 年 28 巻 10 号 p. 876-882
Concerning a heat source model for estimating thermal cycles near the fusion line in an arc welding from the heat conduction theory, the details of the frame model formed by line heat segments which correspond to heat transfers due to the plasma stream and molten metal flow have been proposed and can be determined using a personal computer system designed for the following steps:
1) Rough selection of line segments on the basis of an expert knowledge of the weld pool and simplification for practical use,
2) Evaluation of an effect of each segment on the thermal cycle by the multiple regression analysis, and
3) Checking adaptability of the segments from the distribution of the residuals and the time at a maximum temperature-elevation due toeach segment.
As a result, the model for a given welding condition can be obtained on the basis of the data of the weld penetration measured by many engineers for a long time.
Moreover, the system to predict hardness and microstructural constituents in the heat affected zone and to determine optimum welding conditions has been developed by using an estimated thermal cycle and the database of CCT diagram for welding.
