摘要
针对焊接内部裂纹引起圆环链结构强度减弱的问题,对含内部缺陷的圆环链力学性能进行了研究。首先,针对裂纹的不同分布方式,设定竖向、轴向裂纹,利用增材制造技术对含不同尺寸、不同类型缺陷的圆环链进行了预制;然后,采用单向实验测试方法结合有限元软件,进行了单调拉伸载荷作用下含缺陷圆环链力学性能测试及内部裂纹宏观扩展过程分析,研究了不同尺寸、不同分布方式的内部裂纹对圆环链力学性能的影响;最后,采用循环实验测试方法,开展了循环载荷作用下含缺陷圆环链力学性能测试,研究了不同尺寸与不同分布方式的裂纹条件下圆环链力学性能。研究结果表明:随着轴向、竖向内裂纹尺寸的增加,圆环链试件的延性均呈下降趋势,试件应力均随着裂纹尺寸的增加而减小;圆环链内部裂纹竖向布置时裂纹扩展时间以及断裂时间要比圆环链内部裂纹轴向布置时快;含竖向裂纹的链环在拉伸过程中应力值相比链环含横向裂纹时的应力值分布较小;循环拉伸试件的应力均随着轴向与竖向裂纹尺寸的增加而减小,抗拉强度及延性呈降低趋势,试件裂纹尺寸越小,试件的塑性变形更充分。
In order to solve the problem of weakening the structural strength of the annular chain caused by the internal cracks of welding,the mechanical properties of the annular chain with internal defects were studied.First,according to the different distribution methods of cracks,longitudinal and transverse cracks were set.Additive manufacturing technology was used to prefabricate ring chains with different sizes and types of defects.Then,one-way experimental test method combined with finite element software was used to test the mechanical properties of the defective ring chain under monotonic tensile load and analyze the macroscopic propagation process of internal cracks.The effects of cracks of different sizes and distribution modes on the mechanical properties of annular chains were studied.Finally,the mechanical properties of the toroidal chain with defects under cyclic loading were tested by round-robin experimental test method,and the mechanical properties of the toroidal chain under cracks of different sizes and different distribution modes were studied.The research results show that:with the increase of the size of axial and vertical internal cracks,the ductility of the toroidal chain specimens decreases.The stress of the specimen decreases with the increase of crack size.The crack propagation time and fracture time are faster than those in the axial arrangement of the internal cracks of the ring chain.The stress value of the ring chain with vertical cracks is less distributed during the tensile process than that of the chain link with transverse cracks.The stress of cyclic tensile specimens decreases with the increase of axial and vertical crack sizes,and the tensile strength and ductility tend to decrease.The smaller the crack size of the specimen,the more sufficient the plastic deformation of the specimen.
作者
段九君
武彪
王建勇
哈丽琼
DUAN Jiujun;WU Biao;WANG Jianyong;HA Liqiong(Ningxia Polytechnic University,Yinchuan 750021,China;Shizuishan Wanming Juli Machinery Manufacturing Co.,Ltd.,Shizuishan 753000,China;Yinchuan Hongyida Vocational Skills Training School Co.,Ltd.,Yinchuan 750000,China)
出处
《机电工程》
北大核心
2025年第10期1940-1947,共8页
Journal of Mechanical & Electrical Engineering
基金
宁夏职业技术大学-宁夏开放大学横向科研项目(HX2024078)。
关键词
链传动
刮板输送机
裂纹扩展规律
有限元分析
循环拉伸材料
力学性能
应力循环特征
耗能能力
chain transmission
scraper conveyor
law of crack propagation
finite element analysis
cyclic stretching material
mechanical properties
characteristics of stress cycle
energy consumption capacity
