Q235钢试样低周疲劳过程中表面三维形貌的参数演化规律

为揭示金属低周疲劳过程中表面三维形貌参数演化规律,选取Q235钢试样开展低周疲劳实验,并使用3D轮廓仪获取在同一加载条件、经历不同循环次数的试样表面高度信息,进而对其表面三维形貌进行描述,获取二维粗糙度Ra及三维粗糙度Sa.Vvc.Sal参数特征。结果表明:疲劳过程中表面二维粗糙度Ra及三维粗糙度参数Sa、Vvc、Sal随着疲劳循环次数的增加而增加,且Ra、Sa和Vvc参数在初始与断裂阶段增加幅度较大,中间过程增速较缓。该研究方法及结论可为后续开展形貌相关疲劳寿命评估研究提供基础支撑。

Evolution Law of 3D Morphological Parameters of Q235 Steel Specimen During Low Cycle Fatigue Process

In order to reveal the evolution law of surface three-dimensional shape parameters during low-cycle fatigue of metal,Q235 steel samples were selected to carry out low-cycle fatigue experiments,and 3D profiler was used to obtain surface height information of samples under the same loading conditions and different cycles.Then,the surface three-dimensional shape is described,and the two-dimensional roughness Ra and the three-dimensional roughness Sa,Vvc,and Sal parameters are obtained.The results show that the surface roughness Ra and the three?dimensional roughness parameters Sa,Vvc,and Sal increase with the increase of the number of fatigue cycles,and Ra,Sa The Vvc parameters increase greatly in the initial and fracture stages,and the intermediate process increases slowly.The method and conclusions of this paper can provide basic support for the subsequent research on the appearancerelated fatigue life assessment.