X80管线钢自动焊焊缝冲击能量分配研究OA北大核心CSTPCD

The impact energy distribution and temperature sensitivity of the weld metal were studied using the instrumented impact test method for the automatic weld metal using solid wire for X80 pipe steel.The research results show that the automatic weld metal using solid wire for X80 pipe has good impact toughness(128～195 J)under the condition of common test temperature(-10℃)in engineering.The fluctuation of the total shock absorption energy data is significantly greater than the crack formation energy.It is mainly caused by large fluctuations in the absorption energy during crack propagation;Through a series of temperature tests,it is found that the total absorption energy and crack formation energy have the characteristics of the upper platform,but the upper platform temperature range(-40～20℃)of cracks form energy data curves is larger.With the increase of the test temperature,the proportion of crack formation energy shows a nonlinear decrease in the proportion of crack formation energy.In the design temperature range of long-distance pipeline engineering(-40～20℃),the weld metal crack formation energy test results have temperature-independent characteristics,and the acceptance index is formulated according to the temperature test results of the upper platform,which may not be conducive to the control of weld metal crack initiation.It is suggested that further relevant research should be carried out to formulate the crack toughness index of weld metal,so as to fundamentally control the initiation of weld metal cracks.