【作者】 洪晓祥；

【导师】 陈鹏；

【作者基本信息】 西南交通大学 ， 材料加工工程， 2011， 硕士

【摘要】 随着我国高速铁路的快速发展,高速列车的速度不断的提升,高速列车的生产质量要求也相应的提高。焊接作为高速列车生产的重要手段,焊接残余应力和残余变形一直是生产过程面临的难题,焊接残余变形不仅会影响列车外形的美观,而且会导致车体装配尺寸出现偏差；焊接残余应力对列车的疲劳强度有较大的影响。因此,掌握铝合金焊接残余应力和残余变形规律可以为设计、生产提供帮助。本文使用SYSWELD有限元软件,对某型号的高速列车铝合金车体进行焊接模拟。铝合金车体是由底架、侧墙、车顶等结构组成,使用的材料为A5083P-O、A6N01 S-T5、A7N01S-T4、A7N01S-T5。.在进行焊接模拟过程中,需要提供四种材料的性能参数,如果通过实验测试材料性能参数,所需要的成本较高。因此,本文使用JMatPro4.1软件对四种材料进行计算,并利用获得的不同温度下材料参数建立铝合金材料数据库。通过对铝合金车体构件温度场模拟,获得焊接过程中热量的变化规律及构件经历的热循环曲线,为应力场分析提供依据。利用SYSWELD软件对铝合金车体构件在现有焊接工艺下进行应力场模拟,结合实际测试结果分析焊接残余应力的分布规律。计算结果显示铝合金焊接残余应力的最大值出现在焊缝及近缝区,大小为材料屈服强度的0.6-0.8。改变焊接顺序和约束载荷,分析两者对应力场的影响。更多还原

【Abstract】 With the rapid development of high-speed railway in China, the high-speed train speed is continuously increasing. As a result, the production of high-speed train is Corresponding improved in quality requirements. Welding was regarded as an important means of high-speed train production; the welding residual stress and residual deformation have been a difficult issue in the Production process. Not only does residual deformation of the train affect the appearance of shape, but also it will result in deviation of the body assembly dimensions. Welding residual stress on fatigue strength of the train has a greater impact. Therefore, mastering the alloy welding residual stress and residual deformation can provide help for the design and the production.The S YSWELD software was used in this article. It was used for a type of high-speed train simulation of welding aluminum alloy body. Aluminum body is formed by a chassis, side walls and a roof. The materials used are the A5083P-O, A6N01S-T5, A7N01S-T4 and A7N01S-T5. During the welding simulation, the performance parameters of these materials were needed. If the material properties were tested by experiments, it would need the high cost. Therefore, the JMatPro4.1 software was use to calculate these four materials properties in this article and the materials obtained at different temperatures were used to establish parameters of aluminum alloy material database. The variation of heat obtained in the Welding process and thermal cycling curves of components obtained, provided the basis for the stress field analysis through the simulation of temperature field of aluminum body components. Under the existing welding process, the aluminum alloy bodywork component has been simulated stress with SYSWELD software, and analysis welding residual stress distribution rule combining with actual simulated stress. Calculation results show that the maximum of aluminum alloy welding residual stress is in the weld seam appear near and area, and the size is 0.6 to 0.8 for material yield strength. Change the welding sequence and constraint load, and analyzed the influence to the stress field.更多还原