摘要
热影响区低温断裂韧性是影响9%Ni钢焊接结构安全服役的重要性能指标,裂纹尖端张开位移(CTOD)评定方法具有良好的适用性,但CTOD允许值的合理选用是关键。基于Dugdale-Barrenblett模型,建立了三点弯试样的有限元模型,计算了粗晶区在不同温度和载荷作用下的裂纹尖端张开位移。并在室温和不同低温环境下完成粗晶区CTOD特征值测试。结果表明,低温对9%Ni钢粗晶区CTOD特征值的影响呈现阶段性,从室温到低温的整体降幅较大,深冷环境中的CTOD特征值则较为接近。
The low temperature fracture toughness of heat affected zone is an important performance index affecting the safe service of 9% Ni steel welded structures. The crack tip opening displacement(CTOD) evaluation method has good applicability, but the reasonable selection of CTOD allowable value is the key. Based on Dugdale-Barrenblett model, the finite element model of three-point bending specimens was established, and the crack tip opening displacement of coarse grain region under different temperatures and loads was calculated. The CTOD characteristic values of coarse grain region were tested at room temperature and low temperature. The results show that the effect of low temperature on CTOD characteristic values of coarse grain region of 9% Ni steel is not uniform. The overall decrease from room temperature to low temperature is significant, while the CTOD characteristic value in cryogenic environment is closer.
作者
李宇章
沐卫东
蔡艳
LI Yuzhang;MU Weidong;CAI Yan(Shanghai Key Laboratory of Laser Processing and Material Modification, Shanghai Jiaotong University, Shanghai 200240, China;Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration, Shanghai 200240, China)
出处
《热加工工艺》
北大核心
2019年第15期144-149,共6页
Hot Working Technology
基金
国家重点研发计划项目(2017YFB0305000)
关键词
断裂韧性
9%NI钢
低温
粗晶区
CTOD
fracture toughness
9%Ni steel
low temperature
coarse grained region
CTOD
