Experimental Study on Fracture Toughness of P 280 GH Used in Main Steam Line

The fracture toughness J-R curve of the main steam pipe material is the necessary design input in LBB application.The fracture toughness of P 280 GH used in main steam line was studied by fracture toughness test according to ASTM E1820-2015 a. The results indicated that the toughness of P 280 GH material was good, and the success rate to obtain effective J-R curve was low by the single sample method. Bounding analysis curve (BAC) was constructed by using effective envelope J-R curve parameters.Resultsshowed that all points representing stresses were located under the BAC, meeting the requirements of LBB application.