摘要
为高速车轮服役性能评价及失效分析提供依据,在-60~400℃温度及6.67×10-4~3 782s-1应变速率范围内对高速车轮钢进行拉伸及压缩试验,测量其屈服应力、抗拉强度、断面收缩率、伸长率、应变硬化指数、应变硬化系数等材料力学参量,研究材料力学参量随温度和应变速率的变化。结果表明：在试验范围内高速车轮钢的屈服应力、抗拉强度随应变速率常用对数的升高而线性增加,随温度的升高而基本呈线性降低;屈服应力在试验温度上升范围内下降了225 MPa,在试验应变速率增加范围内上升了270 MPa,而断面收缩率和伸长率则随温度的升高而增加、随应变速率的增加而略有降低;应变硬化指数基本不随温度的变化而变化,但随加载速率的增加而降低;应变硬化系数随温度和应变速率的增加而降低;温度及加载速率对高速车轮钢材料塑性本构关系的定量影响可通过包含温度和应变速率参数的Hollomon方程描述。
Tensile and compression tests were carried out on high speed wheel steel in the range of the temperature from-60 to 400℃and the strain rate from 6.67×10-4 to 3 782s-1 in order to provide the basis for the service performance evaluation and failure analysis of high speed wheel.The yield stress,tensile strength,reduction of area,elongation,strain hardening index and strain hardening coefficient were measured,and the effects of temperature and strain rate on these parameters were studied.The results showed that the yield stress and tensile strength of high speed wheel steel increased linearly with the increase of the common logarithm of strain rate within the test range,but decreased linearly with the increase of temperature.The yield stress decreased 225 MPa with the increase of test temperature from-60 to 400℃and increased 270 MPa with the increase of test strain rate from 6.67×10-4 to 3 782s-1.The reduction of area and elongation increased with the increase of temperature but decreased slightly with the increase of strain rate.The strain hardening index was basically independent of temperature,but decreased with the increase of loading rate.The strain hardening coefficient decreased with the increase of temperature and strain rate.The quantitative effects of temperature and loading rate on the plastic constitutive relation of high speed wheel steel could be described by Hollomon equation including temperature and strain rate parameters.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2015年第3期88-93,共6页
China Railway Science
基金
国家自然科学基金资助项目(51171020
U1234207)
关键词
高速车轮钢
温度
应变速率
力学性能
本构方程
High speed wheel steel
Temperature
Strain rate
Mechanical property
Constitutive equation
