20MnSiVHRB400钢筋的低周疲劳性能分析  

Analysis on High Strain Low Cycle Fatigue Properties of 20MnSiVHRB400 Reinforced Steel Bars

作　　者：秦斌[1] 盛光敏[1] 龚士弘[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400044

出　　处：《重庆大学学报（自然科学版）》2003年第7期93-96,共4页Journal of Chongqing University

摘　　要：对Ф2 5mm和Ф32mm两种规格 2 0MnSiVHRB4 0 0钢筋的高应变低周疲劳性能进行了研究。采用控制总应变幅不变试验 ,测定了 2 0MnSiVHRB4 0 0钢筋高应变低周疲劳过程中的循环应力响应特征、循环应力与应变的关系。用Basquin公式和Manson-Coffin公式拟合得到了两种规格钢筋的疲劳寿命计算公式 ,据此计算了Nf=10 0时的σa·Δεt值 ,发现试验钢筋的高应变低周疲劳性能较 2 0MnSiⅡ级钢筋有了较大的提高。断口扫描发现 ,由于第二相质点和夹杂物的存在 ,形成微孔洞和微裂纹 ,裂纹之间因内颈收缩 。High strain low cycle fatigue properties of 20MnSiVHRB400 reinforced steel bars with diameters of 25 mm and 32 mm were investigated. Based on the tests of total strain controlling, cycle strain response character of 20MnSiVHRB400 and the relationship between cycle stress and strain were researched. Basquin and Manson-coffin formulas were used to induce fatigue life formulas of two kinds of steel bars, and then the values of σ a·Δ ε t were gained when N f=100, calculated results show that the high strain low cycle fatigue properties of steel bars tested are much better than 20MnSiⅡsteel bars. Rupture surface scan reveals that second particles and some other mixtures cause small openings and micro-holes, whose expanding lead to fracture.

关 键 词：钢筋 高应变低周疲劳 疲劳寿命 抗震钢 

分 类 号：TG142.2[一般工业技术—材料科学与工程]