摘要
本文通过设计防屈曲装置,对2.3mm厚度汽车薄板SAPH440在室温下进行了单轴拉伸、低周疲劳和高周疲劳等一系列试验.给出该材料静态力学参数,低周疲劳曲线(E-N曲线)、高周疲劳曲线(S-N曲线)以及相关疲劳性能参数.分别得到了在应力比R=0.1和R=-1状态下的疲劳寿命公式.通过考察低周循环应力-应变曲线,发现材料在试验控制的循环应变幅范围内发生了循环软化,具有明显Masing特性.此外,通过对疲劳断口形貌分析,初步给出了疲劳裂纹的扩展机理.
A series of tests of uniaxial tension, low cycle fatigue, high cycle fatigue were conducted on auto thin sheet SAPH440 with 2.3mm thickness at room temperature. A set of anti-buckling devices was designed to help carry out the tension-compression fatigue test. The static mechanical parameters, low cycle fatigue curve（E-N curve）, high cycle fatigue curve（S-N curve） and relevant fatigue property parameters were obtained. Formula were given to predict fatigue life at stress ratio R equal to 0.1 and-1 respectively. From the low cycle stress-strain curve, it can be seen that cyclic softening occurred to the material at the controlled cyclic strain amplitudes, indicating obvious massing properties. In addition, the preliminary mechanism of fatigue crack propagation is presented through fatigue fracture morphology analysis.
出处
《力学季刊》
CSCD
北大核心
2016年第3期559-564,共6页
Chinese Quarterly of Mechanics
基金
国家自然科学基金(11102107)
上海市自然科学基金(16ZR1417700)
关键词
SAPH440
薄板材料
高低周疲劳
应变控制
疲劳性能
SAPH440
thin sheet material
high and low cycle fatigue
strain controlled
fatigue property
