【摘要】 采用多试样方法,应用国内外不同标准测试了X56管线钢焊接接头的低温(-5℃)J-R曲线并对结果进行了分析比较。采用两个夹式引伸计在-5℃下分别得到焊缝和热影响区(HAZ)的双P-V曲线来计算施力点位移,从而得到J积分值。然后对数据点分别根据国家标准GB2038—91和英国标准BS7448进行处理。结果表明,BS7448标准在钝化线、各界限确定等方面存在着很大的优越性,能够拟合得到J-R曲线,计算出J0.2,确定了材料的断裂韧度。而根据国家标准GB2038—91没有合格数据点,从而不能进行断裂韧度的计算。更多还原

【Abstract】 According to different fracture toughness test standard, J-Resistance curve tests were conducted at-5℃ in welded joints of X56 pipeline steel in the multiple specimen method and the test result were compared. According to the double P-V curves of each weld metal and heat affected zone specimen obtained from the two notch opening displacement the load-line displacement and the value of J were calculated. Finally, the best fited curve was determined the valid data points according to GB2038-91 and BS7448, respectively. The result indicates that BS7448 is superior to GB2038-91 on blunt line, exclusion lines and so on. J-Resistance curves and J_ 0.2 was obtained. But there are no valid data points according to GB2038-91 and no further calculation.更多还原