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- Restraint (4)
- Austenitic stainless steels (3)
- Cold cracking (3)
- Heat affected zone (3)
- Mechanical properties (3)
- Residual stresses (3)
- Steels (3)
- Weldability tests (3)
- Cooling (2)
- Cracking (2)
Organisationseinheit der BAM
Up to the present, the thermomechanical loads during welding and subsequent cooling under design-specific shrinkage restraint resulting from the interaction between the materials and the structure have often not been taken into consideration approperiately for weldability assessment of components. As compared to previous investigations using small specimens this report presents component weld tests under varying intensities of restraint. Online records of the reaction forces and moments demonstrate in which way the intensity of restraint affects the reaction stresses and moments and their meaning for the evaluation of the load level in welded components.
This study provides an in-depth survey of current technologies and applications for assessing the cold cracking susceptibility of welded joints. From the large variety of existent cold cracking test procedures, the most important and internationally established tests are presented and evaluated in terms of their usefulness and application limits. According to the type of loading, the test procedures are classified into self-restraint and externally loaded tests. Apart from the merely metallurgical weldability tests for determining the cracking susceptibility of base materials, filler materials and weld metals, advanced test methods are presented for evaluating the cold cracking susceptibility of welded components. A salient point brought out in this respect is the fact that the level of external loading in such component weld tests can be applied independently of the welding parameters, reproducing as realistically as possible the practical application case, i.e. the level of the restraint intensity. This study includes a summarized comparison of the cold cracking procedures. It is emphasized that highly accurate consideration and reproduction of the design-specific stiffness conditions is essential in the tests for assessing the cold cracking behaviour of welded joints. Therefore, various numerical analyses are presented in a final chapter for calculating the restraint intensity as a definitive factor affecting cold cracking.