摘要
特种车辆设备中的异种金属焊接件是影响其使用性能的关键部位,而且不同的工作温度也会对裂纹的断裂行为产生不同的影响.为了研究温度对异种金属焊接件准静态断裂扩展的影响,本文以细化裂纹尖端网格的扩展有限元为基础,利用考虑热载荷作用下的相互作用积分,构建了热载荷作用下焊接区域裂纹尖端应力强度因子的计算方法和对不同温度下裂纹准静态扩展路径的模拟方法,并与解析解对比证明了应力强度因子计算方法的正确性和积分区域无关性.本文研究对于特种车辆的使用性能预测具有十分重要的工程意义.
Dissimilar metal welds in special vehicles and equipment are essential parts that significantly influence their performance.This study focuses on how different working temperatures affect crack propagation behavior in these welds.The research employs the extended finite element method(XFEM)as its numerical analysis tool.By refining the local mesh at the crack tip,it avoids complex crack-tip field enhancement function found in traditional methods.Temperature effects are integrated into the interaction integral,and its form is simplified to isolate terms related to material properties and temperature.The method for extracting mode Ⅰ and mode Ⅱ stress intensity factors is provided.Thus,a numerical calculation method for the stress intensity factor at the crack tip of dissimilar metal welds in special vehicles has been established.Taking a two-dimensional infinite plate with a crack as an example,stress intensity factors are calculated under various temperature loads and crack lengths and compared with the analytical solution.It is found that the relative error between the two is less than 1.3%,and changes in different integration regions have minimal impact on results.The correctness and integral region independence of this method have been verified.Then,based on the maximum circumferential stress criterion and the above research content,a quasi-static crack growth numerical simulation method is established for different temperatures.Simulations are conducted at low,normal,and high temperatures to examine crack propagation paths at various locations.Initial crack growth angles and paths reveal that crack propagation in the welding zone is predominantly mode Ⅰ at normal temperatures.However,low and high temperatures have opposite effects on crack direction.Additionally,cracks may propagate across weld boundaries.This finding significantly advances the prediction of performance at different working temperatures in dissimilar metal welds of special vehicles and provides crucial guidance for durability and safety design in engineering applications.
作者
王标
尚杰
赵波
梁展搏
于红军
Biao Wang;Jie Shang;Bo Zhao;Zhanbo Liang;Hongjun Yu(Shanghai Electro-mechanical Engineering Institute,Shanghai,201109;Department of Astronautic Science and Mechanics,Harbin Institute of Technology,Harbin,150001)
出处
《固体力学学报》
北大核心
2025年第2期218-229,共12页
Chinese Journal of Solid Mechanics
