基于分子动力学的金属钛纳米振动切削仿真研究

发布时间：2018-01-17 15:32

本文关键词：基于分子动力学的金属钛纳米振动切削仿真研究　出处：《沈阳航空航天大学》2016年硕士论文　论文类型：学位论文

【摘要】：作为现代航宇、国防工业高精尖产品的支撑材料,金属钛的超精密加工精度需求已越来越高,加工精度已达到纳米级别,这对实际的加工实验提出了很高要求,同时纳米切削机理以及加工中出现的材料微观结构、微磨损和尺寸效应等问题也都和常规切削存在很大差别。分子动力学仿真(Molecular dynamics simulation,MDS)可以解决以上问题,它从研究微观领域探索物质的宏观特性,是从分子、原子的角度研究微、纳米加工机理的可行方法。本文利用分子动力学(Molecular dynamics,MD)的基本理论和方法,结合振动辅助切削(Vibration-assisted Machining,VAM)技术,确定了适合金属钛纳米振动切削的MDS方法,从分子、原子的微观角度研究了金属钛的纳米振动切削过程。首先,本文对MD和振动切削技术的研究现状以及理论方法进行了介绍,运用MD基本理论,建立了适合金属钛的纳米振动切削MDS模型,并开发了相应的仿真程序。其次,确定了合理的仿真条件,对建立的纳米振动切削模型进行弛豫,得到弛豫过程的势能变化曲线。再次,进行了金属钛纳米振动切削过程的MDS模拟,得到了普通切削、单向振动以及EVC切削模式下的瞬时原子位置图像、切削力以及切削温度曲线,并且将模拟结果进行对比与分析。最后,通过仿真不同振动(切削)参数下的纳米加工过程,分析对金属钛纳米振动切削过程中切削力和切削温度等的影响规律。
[Abstract]:As the support material of advanced products in modern aviation and national defense industry, the requirement of ultra-precision machining precision of titanium metal has been higher and higher, and the machining precision has reached the nanometer level, which puts forward a very high requirement for practical processing experiments. At the same time, the mechanism of nano-cutting and the microstructure of materials appeared in machining. The problems of micro-wear and size effect are also very different from conventional cutting. Molecular dynamics simulation of molecular dynamics simulation. MDS) can solve the above problems by exploring the macroscopic properties of matter from the micro field and studying micro from the point of view of molecules and atoms. The basic theories and methods of molecular dynamics molecular dynamics (MD) are used in this paper. Combined with Vibration-assisted Machining (VAM) technology, the MDS method suitable for nano-vibration cutting of titanium metal was determined. The nano-vibration cutting process of titanium metal is studied from the microcosmic angle of atoms. Firstly, the research status and theoretical methods of MD and vibration cutting technology are introduced in this paper, and the basic theory of MD is used. The MDS model of nano-vibration cutting suitable for metal titanium is established and the corresponding simulation program is developed. Secondly the reasonable simulation conditions are determined to relax the established nano-vibration cutting model. The potential energy curves of the relaxation process were obtained. Thirdly, the MDS simulation of the metal titanium nano-vibration cutting process was carried out, and the instantaneous atomic position images in the normal cutting mode, the unidirectional vibration mode and the EVC cutting mode were obtained. The cutting force and cutting temperature curve are compared and analyzed. Finally, the nanocrystalline machining process under different vibration (cutting) parameters is simulated. The influence of cutting force and cutting temperature on the vibration cutting process of titanium nanocrystalline was analyzed.
【学位授予单位】：沈阳航空航天大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TG506.5

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