X90和X100管线钢管HAZ夏比冲击韧性研究

摘要

The Charpy impact test was conducted on X90 and X100 line pipe respectively, it found the toughness of weld HAZ reduces. Through observing metallographic structure, it found lath martensite structure appeared in HAZ in different degree. Through hardness test, it regarded that the presence of the rigid lath martensite decreases weld HAZ toughness index, it is the major reason caused unqualified Charpy impact toughness. The weld HAZ impact toughness of sample were improved evidently after tempering heat treatment under different temperature, it indicated heat treatment can effectively reduce and eliminate the influence of quenched hard structure to weld HAZ impact toughness.%对X90和X100管线钢管进行了夏比冲击试验，发现焊缝HAZ韧性有所降低，通过金相组织观察，发现热影响区出现不同程度的板条马氏体组织，经过硬度试验，认为脆硬的板条马氏体的出现降低了焊缝HAZ的韧性指标，是夏比冲击性能不合格的主要原因。将试样在不同温度下进行回火热处理后焊缝HAZ的韧性性能均有明显提高，说明通过热处理能有效地降低甚至消除淬硬组织对焊缝热影响区冲击韧性的影响。