铝合金复杂薄壁件精密加工技术研究

发布时间：2018-02-28 20:10

本文关键词： 铝合金薄壁件有限元低应力振动时效检测技术　出处：《北华航天工业学院》2017年硕士论文　论文类型：学位论文

【摘要】：铝合金复杂薄壁件由于具有良好的综合力学性能,已被广泛用于导弹武器装备系统、航空航天产品中,但其在实际加工生产中存在变形难控制、高精度尺寸及形位公差无法保证的问题,追求结构材料的轻量化,导致其无法满足设计使用要求,使其在实际生产中受到制约。本文针对实际加工中遇到的几个主要因素,采用理论和实践相结合的方法,对铝合金复杂薄壁件精密加工技术进行了研究。本文具体研究内容如下:首先,对影响精密加工变形的残余应力进行研究,找出合适的测量方法。应用频谱谐波振动时效的方法消除残余应力,在此基础上建立了有限元振动时效仿真模型,优化了进给量、转速、切深等主要切削工艺参数,给出了消除内应力振动时效参数,并通过试验的方法进行验证,为控制加工变形提供了理论依据。然后,分析了低应力装夹过程对精密加工的影响,建立综合工件-工装的刚度分析模型,利用有限元仿真技术分析对比了不同装夹下应力及变形情况,得出最优的装夹方案,并对装夹及采样点的分布确定进行了研究,研究优化切削许用值对精密加工变形的影响,分析得出最优的参数组合,实现低应力装夹在精密加工中的优化应用。最后,对结构件进行了精密加工性能的检测和分析,以验证结构件是否满足型号使用要求。其中三维尺寸、内部质量、表面粗糙度、残余应力检测用于结构件质量与缺陷检测,模态、振动试验用于验证结构件性能是否满足使用需求。
[Abstract]:Aluminum alloy complex thin-walled parts have been widely used in missile weapon systems and aerospace products because of their good comprehensive mechanical properties, but the deformation is difficult to control in actual processing and production. The problems of high precision size and tolerance of shape and position can not be guaranteed, and the pursuit of lightweight structural materials leads to its inability to meet the requirements of design and use, which makes it restricted in actual production. This paper aims at several main factors encountered in practical processing. The precision machining technology of complex thin-walled aluminum alloy is studied by combining theory and practice. The main contents of this paper are as follows: firstly, the residual stress which affects the deformation of aluminum alloy is studied. The method of spectrum harmonic vibration aging is used to eliminate residual stress. On this basis, the finite element simulation model of vibration aging is established, and the main cutting process parameters, such as feed rate, rotational speed and cutting depth, are optimized. The vibration aging parameters for eliminating internal stress are given and verified by experimental method, which provides a theoretical basis for controlling machining deformation. Then, the influence of low stress clamping process on precision machining is analyzed. The stiffness analysis model of integrated workpiece and tooling is established. The stress and deformation under different clamps are analyzed and compared by using finite element simulation technology. The optimal clamping scheme is obtained, and the distribution of clamping and sampling points is studied. The effect of the allowable value of optimal cutting on the deformation of precision machining is studied, and the optimal parameter combination is obtained to realize the optimal application of low stress clamping in precision machining. Finally, the precision machining performance of structural parts is tested and analyzed. In order to verify that the structural parts meet the requirements of the use of the model. The three-dimensional dimension, internal quality, surface roughness, residual stress detection for structural quality and defect detection, modal, Vibration tests are used to verify that the performance of the structure meets the operational requirements.
【学位授予单位】：北华航天工业学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG156.92;TG506

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