管线钢平面应变断裂韧性经验模型研究

为了研究高钢级管线钢断裂韧性受试样厚度影响的变化规律,对X80管线钢不同厚度的试样进行了系列断裂韧性试验,建立了X80管线钢平面应变断裂韧性和临界壁厚关系的经验估算模型。基于试验结果以及三维断裂力学理论和准则,对所建立的经验模型进行了验证。结果表明,对于X80管材,平面应变的临界壁厚大约在50 mm,与厚壁弯管的爆破试验结果基本吻合;经验估算模型的预测结果较为准确,能够满足工程应用的需要。

Study on Empirical Model of Plane Strain Fracture Toughness for Pipeline Steel

The high grade pipeline steel fracture toughness is affected by specimen thickness, in order to study the influence change rule, a series of fracture toughness tests were carried out for different thickness X80 pipeline steel specimen. The empirical estimation model between X80 pipeline steel plane strain fracture toughness and critical wall thickness was established. Based on test results and three-dimensional fracture mechanics theory and criterion, the empirical model was validated. The result showed that, for X80 pipe material, the critical wall thickness of plane strain is about 50 mm, it is basic consistent with the blasting test results of thick wall bends; the predicating results of experience estimation model are more accurate, can meet the requirements of engineering application.