2004 年 22 巻 1 号 p. 94-100
It is an important subject to clarify the mechanism of welding crack formation to eliminate defects in welds in structures. Thus, the authors developed a finite element method (FEM) using temperature dependent interface elements in order to analyze all the processes of the crack formation, propagation and its arrest. The proposed method is applied to the Trans-Varestraint hot cracking test and the influences of the parameters included in the interface element are clarified. In the proposed model of hot cracking, the scale parameter r0 and BTR (Brittleness Temperature Range) need to be determined. If these parameters for alloys with different chemical compositions are accumulated as a database, the formation and propagation of hot cracking can be predicted for wide range of materials used in real welded structures. The procedure to determine the values of these parameters is proposed. Further, the validity or the general applicability of the parameters as material constants is demonstrated through the cross examination between the Trans-Varestraint test and the Houldcroft test. From these results, it is found that the results of experiments and computations agree well with each other quantitatively for both of the hot cracking tests. This suggests that the formation and propagation of hot cracking can be predicted using the proposed method.