海洋平台E36钢热处理前后断裂韧性研究

Research on Fracture Toughness of E36 Steel of Offshore Platform before and after Heat Treatment

摘要: 工程上普遍认为，通过焊后热处理（PWHT），如果方法得当，可以提高焊缝金属的断裂韧性值。但是，近年来诸多研究发现，焊后热处理对断裂韧性也并不是都有好的影响，比如，热处理之后，焊接接头热影响区的断裂韧性就可能有恶化的现象。本研究设计了对比CTOD（裂纹尖端张开位移）试验，发现热处理之后热影响区组织变粗大，碳化物大量析出并聚集长大，使得断裂韧性大大降低。

Abstract: Recently, several tests have indicated that post-weld heat treatment(PWHT) may not always have positive influence on the fracture toughness, contradictory to general consensus. For example, the fracture toughness of heat-affected zone may be worse after PWHT. Several crack tip opening displacement (CTOD) tests were conducted and the results showed that the microstructures would be coarser and carbide precipitated, which made the fracture toughness worse.