不同冷却方式锈蚀冷弯薄壁型钢材高温后力学性能  

Mechanical properties of corroded cold-formed thin-walled steel after high temperature under different cooling methods

作　　者：吕晶[1] 郑健龙 王璐瑶 韩文超 尹豪 LÜJing;ZHENG Jianlong;WANG Luyao;HAN Wenchao;YIN Hao(School of Civil Engineering,Chang′an University,Xi′an 710061,China)

机构地区：[1]长安大学建筑工程学院,西安710061

出　　处：《哈尔滨工业大学学报》2025年第2期90-103,共14页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金(51908046);陕西省重点研发计划(2023-YBSF-219);中国博士后基金(2019M653517);长安大学中央高校基本科研业务费专项资金(300102281204)。

摘　　要：为研究冷弯薄壁型钢材料在高温和锈蚀耦合作用下力学性能变化规律,通过中性盐雾锈蚀、高温煅烧、冷却和拉伸试验,对180个经历0~60 d人工加速锈蚀和20~800℃高温煅烧后1.5 mm厚S280GD+Z型冷轧薄钢板在自然冷却和浸水冷却方式下的力学性能进行了试验研究。结果表明:在锈蚀和高温耦合作用下,钢材表面特征和破坏模式受冷却方式影响较大;锈蚀率小于6%时,锈蚀对S280GD+Z钢材力学性能影响较小;受火温度低于600℃时,受火温度及冷却方式对S280GD+Z钢材屈服强度、极限强度影响不显著;在锈蚀和高温耦合作用下,受火温度大于600℃后,钢材强度退化幅度变大并且高温在对钢材强度影响中占主导地位;冷却方式对钢材伸长率影响较大,自然冷却条件下,伸长率随受火温度呈先增加后减小趋势,浸水冷却条件下,伸长率随受火温度整体呈降低趋势。建立了锈蚀与高温耦合作用下,S280GD+Z钢材力学参数与锈蚀率、受火温度之间定量关系的数学模型,基于简化的二次塑流模型建立了锈蚀与高温耦合作用下S280GD+Z钢材本构模型。In order to study the variation of mechanical properties of cold-formed thin-walled steel materials under the coupling effect of high temperature and corrosion,a series of experiments involving neutral salt spray corrosion,high-temperature calcination,cooling and tensile tests were conducted.The mechanical properties of 180 S280GD+Z cold-rolled steel sheets with thickness of 1.5 mm,which underwent accelerated corrosion for 0-60 d and high temperature calcination from 20 to 800℃,were studied under cooling in air and cooling in water.The results indicate that under the coupling effect of corrosion and high temperature,the surface characteristics and failure modes of the steel are greatly affected by the cooling methods.When the corrosion rate is less than 6%,the corrosion has little impact on the mechanical properties of S280GD+Z steel.When the fire temperature is below 600℃,the fire temperature and cooling methods have insignificant effects on the yield strength and ultimate strength of S280GD+Z steel.However,under the coupling effect of corrosion and high temperature,when the fire temperature exceeds 600℃,the strength degradation of steel becomes the dominant factor affecting the strength of steel.The cooling method has a significant impact on the elongation of the steel.Under natural cooling conditions,the elongation increases and then decreases with the increase in fire temperature.Under immersion cooling conditions,the elongation shows an overall decreasing trend with the increase in fire temperature.A mathematical model was established to quantify relationship between the mechanical parameters of S280GD+Z steel and the corrosion rate and temperature under the coupling effect of corrosion and high temperature.Based on a simplified secondary plastic flow model,a constitutive model for S280GD+Z steel under the coupling effect of corrosion and high temperature was established.

关 键 词：高温 锈蚀 耦合作用 冷弯薄壁型钢 力学性能 

分 类 号：TU398[建筑科学—结构工程]