腐蚀后Q355GNH耐候钢力学性能分析及本构模型研究
Research on Mechanical Properties and Constitutive Model of Q355GNH Weathering Steel After Corrosion Damage
兰涛 1康蕾 1李然 2李泽旭 2秦广冲 2张博雅3
作者信息
- 1. 中国船舶集团国际工程有限公司,北京 100121;同济大学材料科学与工程学院,上海 201804
- 2. 中国船舶集团国际工程有限公司,北京 100121
- 3. 四川省建筑设计研究院有限公司,成都 610041
- 折叠
摘要
对 Q355GNH 耐候钢开展了模拟工业海洋大气腐蚀环境乙酸盐雾试验,分析了其耐蚀性能,并通过单调拉伸试验研究腐蚀率对其力学性能指标退化的影响规律,建立了 6、14 mm厚度的耐候钢锈损本构关系模型.研究结果表明:腐蚀导致耐候钢强度降低、延伸率减小,其中腐蚀率对断裂应变的影响最大,其次是屈服强度和极限强度,腐蚀后耐候钢屈强比稳定,拉伸断裂形式仍为韧性断裂;钢材厚度越小,腐蚀后钢材承载力下降越明显;随着腐蚀率增加,钢材应力-应变曲线的屈服平台、塑性强化阶段缩短,腐蚀 40 天后 6 mm厚板件的屈服平台消失.基于未腐蚀耐候钢本构关系,通过引入参数k1、k2、k3、C,提出了相应厚度的锈蚀耐候钢本构模型,与试验获得的应力-应变曲线各阶段吻合良好.
Abstract
In this study,acetic acid salt spray test was carried out on Q355GNH weathering steel,and its weathering performance in industrial marine atmospheric corrosion environment was analyzed.After the cor-rosion tests,the monotonic tensile test was carried out to study the degradation trend of the mechanical properties of pre-corroded Q355GNH with the increase of corrosion rate,and the corrosion damage constitu-tive model of Q355GNH with 6 mm and 14 mm thickness was established.The results showed that the ten-sile strength and elongation of the weathering steel decreased after corrosion.The corrosion rate had the greatest influence on the fracture strain,followed by the yield strength and ultimate strength;the yield ratio of weathering steel was always stable after corrosion,and the tensile fracture mode was still ductile fracture;the smaller the thickness of steel was,the more obvious the decrease of mechanical properties of steel after corrosion was;with the increase of corrosion time,the constitutive curve of Q355GNH steel changed,the yield platform and plastic strengthening stage gradually became shorter,and the yield platform of 6 mm ma-terial specimen disappeared just after 40 days of corrosion.Based on the constitutive model of Q355GNH weathering steel with smooth surface,the constitutive model of pre-corroded weathering steel was proposed by introducing parameters k1,k2,k3,C,which was in good agreement with the constitutive curve of Q355GNH after corrosion.
关键词
Q355GNH耐候钢/耐蚀性能/本构模型/力学性能Key words
Q355GNH weathering steel/corrosion resistance/constitutive model/mechanical properties引用本文复制引用
出版年
2024
NETL
NSTL
万方数据