基于边界效应理论确定热轧碳素钢的韧度与强度  

DETERMINATION OF FRACTURE TOUGHNESS AND YIELD STRENGTH OF HOT ROLLED CARBON STEEL BASED ON BOUNDARY EFFECT THEORY

作　　者：管俊峰 谢超鹏 HU Xiao zhi 姚贤华 白卫峰 GUAN Jun-feng;XIE Chao-peng;YAO Xian-hua;BAI Wei-feng(School of Civil Engineering and Communication, North China University of Water Resources and Electric Power, Zhengzhou, Henan 450045, China)

机构地区：[1]华北水利水电大学土木与交通学院,河南郑州450045 [2]School of Mechanical and Chemical Engineering, University of Western Australia

出　　处：《工程力学》2019年第3期231-239,共9页Engineering Mechanics

基　　金：国家自然科学基金面上项目(51779095;51679092);郑州市科技攻关项目(153PKJGG111;153PKJGG109)

摘　　要：该文研究确定热轧碳素钢的材料韧度与强度特性,提出一种确定热轧碳素钢材料的断裂韧度与屈服强度的模型及方法。建立了等效裂缝长度、名义应力等具体设计参数的计算表达式。通过相同尺寸而不同初始缝高比的单边拉伸Q235B热轧碳素钢板的系列试验,证明所提模型及方法的合理性与适用性。所提模型及方法只需由小尺寸单边裂缝钢板的拉伸试验测得的屈服荷载,即可同时确定出热轧碳素钢平面应力条件下的断裂韧度KC及屈服强度?Y。采用该文所提方法确定热轧碳素钢的材料特性,试验试样不需要满足现行国内外规范对试验试样尺寸、型式,加载条件等的严格规定,试样不需要预制疲劳裂纹。The material properties of hot rolled plain carbon steel were studied using boundary effect theory,linked to the properties of toughness and strength. The method for determining the fracture toughness and yield strength of hot rolled plain carbon steel was proposed. The formulas for design parameters ae and σn were obtained. Based on the experimental research on the identical size steel plates of Q235 under tension with different a-ratio=a0/W(ratio of initial cracks a0 and plate size W), the reasonability and availability of this model and appropriate method were experimentally confirmed. The plain stress fracture toughness and yield strength can be measured through the small size single edge notch test(SENT) hot rolled plain carbon steel specimens of a single size with different initial cracks. On top of that, the specimens using this proposed method do not meet the size, pattern and loading requirement from current codes, and do not need the fatigue cracks.

关 键 词：边界效应理论 热轧碳素钢 断裂韧度 屈服强度 平面应力 

分 类 号：TG142.1[一般工业技术—材料科学与工程]