A fracture criterion for welded joints with internal defects

The development of procedures for the rapid detection of hazardous defects in welded joints during diagnostic tests is an important component of the set of measures to ensure the safe operation of technical objects. A fracture criterion of welded joints with pore or inclusiontype defects is proposed. This criterion is sufficiently simple and accurate to determine the maximum permissible load acting on the defective welded joint if the defect size and weld metal properties are known. The results of breaking tests of butt welds with internal defects are presented. Scientific experiments are conducted to study the mechanical properties of the weld metal. It is shown that the danger of welding defects of this type can be estimated using classical theories of strength by solving the corresponding elastoplastic problem. However, this approach is impractical under actual production conditions due to its complexity and the need to involve qualified designers.

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