摘要
该文建立了预测低合金钢结构断裂破坏的弹塑性断裂理论与模型。将两个独立判据 强度及韧度准则联系起来,搭起结构特性与材料参数间的纽带桥梁:可由处于弹塑性断裂控制的小尺寸低合金钢试样的结构特性确定其材料参数;基于确定的材料参数,可建立起预测低合金钢结构破坏的全过程曲线。该文进行了多组相同尺寸而不同裂缝长度的 Q345B 钢的单边拉伸试验,基于所提模型及试验结果,确定出无尺寸效应的断裂韧度、屈服与极限强度等材料参数;进而构建了可涵盖所有试验点的 Q345B 钢的安全设计曲线(±10%界限)。研究成果可为确定金属材料参数及预测金属结构破坏提供新思路。
It proposes an elastoplastic fracture theory and an associated model that can be used to predict the fracture of low-alloy high-strength steel specimen. By combining two independent criteria for material parameters, namely strength and fracture toughness, this model further establishes the link between structural characteristics and material parameters. Only structural characteristics obtained from the tensile test of small-size specimen in elastoplastic fracture status are required to de’termine the material characteristics of low-alloy high-strength steel. The elastoplastic fracture of low-alloy high-strength steel structure is predictable with the simple model if the strength and fracture toughness are available. Single-edge-notch specimens of low-alloy high-strength steel Q345B with identical size but different notch lengths under tension were tested. The independent material parameters of Q345B, such as fracture toughness under plane stress condition, yield strength, ultimate strength, and other material characteristics were determined using the proposed model. The safety-design diagrams with upper and lower limits (±10%) that can cover all test results were constructed. It provides a new idea for the determination of material parameters and prediction of the structure fracture of metals.
作者
管俊峰
宋志锴
白卫峰
姚贤华
陈珊珊
谢超鹏
GUAN Jun-feng;SONG Zhi-kai;BAI Wei-feng;YAO Xian-hua;CHEN Shan-shan;XIE Chao-peng(School of Civil Engineering and Communication,North China University of Water Resources and Electric Power,Zhengzhou,Henan 450045,China)
出处
《工程力学》
EI
CSCD
北大核心
2020年第1期218-229,共12页
Engineering Mechanics
基金
国家自然科学基金面上项目(51779095
51679092)
河南省高校科技创新人才支持计划项目(20HASTIT013)
关键词
低合金钢
结构特性
材料特性
弹塑性断裂
断裂韧度
强度
low-alloy high-strength steel
structural behavior
material behavior
elastoplastic fracture
fracture toughness
strength
