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.
出处
《重庆大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2003年第7期93-96,共4页
Journal of Chongqing University
关键词
钢筋
高应变低周疲劳
疲劳寿命
抗震钢
steel bar
high strain low cycle fatigue
fatigue life
anti-seismic steel
