热风铜钎焊炉热处理后不锈钢力学性能试验研究  

Experimental Study on Mechanical Properties of Stainless Steel after Heat Treatment in Hot Air Brazing Furnace

作　　者：吴佳东 颜东煌 许红胜 张超 潘权 陈星烨 WU Jiadong;YAN Donghuang;XU Hongsheng;ZHANG Chao;PAN Quan;CHEN Xingye(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China;Broad Sustainable Building Co.Ltd,Yueyang 414600,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114 [2]远大可建科技有限公司,湖南岳阳414600

出　　处：《湖南大学学报（自然科学版）》2022年第3期43-56,共14页Journal of Hunan University:Natural Sciences

基　　金：国家重点基础研究计划(973计划)资助项目(2015CB057706);国家自然科学基金资助项目(51678068,51878073)。

摘　　要：为了研究国产奥氏体S30408不锈钢桥面芯板的材料力学性能及其本构关系,开展了多种不锈钢试件室温单向拉伸试验研究.考虑试件厚度、取向和热风升降温处理等因素,共设计了12组共60个拉伸试件,得到不锈钢试件的名义应力-应变曲线及初始弹性模量、屈服强度、抗拉强度、应变硬化指数等参数,揭示了厚度和取向对不锈钢试件力学性能参数的影响程度,并将试件的名义应力-应变试验曲线与经典本构模型进行对比分析.结果表明:不锈钢材料具有明显的非线性与各向异性;通过SEM扫描电镜微观形貌分析,确定不锈钢断口属于韧性断口;不锈钢原材料8 mmS型试件塑性比6 mmS型试件好,而8 mmQ型试件塑性比6 mmQ型试件差;芯板轧制方向的试件伸长率与收缩率要高于垂直于轧制方向试件与斜向45°试件;经热风铜钎焊炉高温处理后的不锈钢材料力学性能明显改变,屈服强度与抗拉强度较不锈钢原材料低,塑性性能变差,但初始弹性模量几乎不变;应变ε<ε_(0.2)时,各本构模型与试验曲线拟合良好,但应变ε≥ε_(0.2)时,R-O模型结果偏差大,Rasmussen模型拟合效果最好,可适用于不锈钢芯板结构的设计和研究.In order to study the material mechanical properties and constitutive relationship of domestic austen⁃itic S30408 stainless steel bridge deck sandwich panel,uniaxial tensile tests of various stainless steel specimens were carried out at room temperature.Considering several parameters including the thickness,orientation,and hot air heating and cooling treatment of specimens,a total of 12 groups of 60 tensile specimens were designed.The nominal stress-strain curve and parameters such as initial elastic modulus,yield strength,tensile strength,and strain harden⁃ing index of stainless steel specimens were obtained,the influence degree of thickness and orientation on mechanical properties of stainless steel specimens were revealed,and the nominal stress-strain test curves of the specimens were compared with the classical constitutive models.The results show that stainless steel has obvious nonlinearity and an⁃isotropy;the microscopic morphology is analyzed by SEM,and it is determined that the fracture of stainless steel be⁃longed to ductile fracture;8 mm S type specimens have better plasticity than 6 mm S type specimens for the stainless steel,and the plasticity of 8 mm Q type specimens are worse than that of 6 mm Q type specimens;the elongation and shrinkage of specimens in the rolling direction of sandwich panel are higher than those in the vertical rolling direc⁃tion and the oblique 45°;the mechanical properties of stainless steel are obviously changed after high-temperature treatment in hot air brazing furnace,the yield strength and tensile strength are lower than those of stainless steel,and the plasticity is worse,but the initial modulus of elasticity is almost constant;whenε<ε_(0.2),each constitutive models fit well with the test curves,but whenε≥ε_(0.2),R-O model has a large deviation.Rasmussen model has the best fit⁃ting effect and can be applied to the design and research of stainless steel sandwich panel structures.

关 键 词：桥梁结构 本构关系 试验研究 不锈钢芯板 力学特性 

分 类 号：U443.5[建筑科学—桥梁与隧道工程]