【作者】 潘艳；

【导师】 计时鸣； 王忠飞；

【作者基本信息】 浙江工业大学 ， 机械电子工程， 2009， 硕士

【摘要】 模具制造中存在大量的细小结构化表面,受尺寸形状限制,难以使用工具进行接触式光整加工,为此,提出一种基于“软性”磨粒流的模具结构化表面光整加工新方法,其特色为:1)设计约束模块与结构化表面组合,构成特定形状的磨料流道,利用软性磨粒流弱黏或无黏特点,使其在流道中形成湍流流动,并可流入任何复杂截面流道,与壁面形成良好接触;2)利用湍流中磨粒对壁面的频繁微力微量切削实现光整加工,切削方向的随机性消除了表面纹理的明显方向趋势,有助于实现镜面级加工;3)磨粒在流动中受流道约束,对表面进行反复碰撞,可有效提高加工效率。本文研究的内容主要包括以下几个部分:1)本文介绍了“软性”液-固两相磨粒流精密光整加工的研究意义,并概括了国内外该方面的研究现况,提出了基于“软性”液—固两相磨粒流的模具结构化表面光整加工的方法,并分析了其原理。根据原理设计并加工了试验平台和约束模块。2)给出了“软性”液—固两相磨粒流加工的控制方程,设计了矩形截面流道,并对矩形截面流道以及管道等进行一系列的Fluent仿真,包括压力场和速度场的仿真,不同矩形截面流道的数值模拟等。3)最后在加工完成的试验平台和约束模块上进行了一系列的验证试验,验证了其原理的正确性和该方法的可行性。然后进行了基于正交试验法的九组工艺试验,并对试验数据进行了分析,得到了系统脉冲压力峰值P,抛光时间T,流量qv等3个参数对加工效果的影响曲线。从试验中得到结论,三个因素对试验结果的影响主次顺序为:脉冲压力峰值＞抛光时间＞设定流量,从试验最优条件组合可以得知,较大脉冲压力峰值P为,较长抛光时间T和较大设定流量qv可以得到较好的加工效果。最后根据试验数据推导出经验公式。更多还原

【Abstract】 There are a lot of tiny structural surfaces in mould manufacture. They can’t be polished by tools because of the little size or the shape. Therefore, a new method of the technologic research of mould structural surface polishing processing based on flexible liquid-solid two phase abrasive flow is brought forward. The characteristic of this method are: 1) The special flow passage is formed from the designed restricted module in combination with the structural surface. Based on the low viscosity or zero viscosity of the flexible abrasive flow, the turbulent flow is formed in the flow passage, and flow into any complicated section flow passage. The walls of the mould is well touched by the flow; 2) The polishing machining based on the frequent low-strength low-speed cutting by the abrasive grain of turbulent flow to the wall of work piece is good for the mirror finishing, because the random of the cutting direction eliminates the direction tendency of surface veins. 3) Abrasive grains are restricted by the flow passage. They hit the surface again and again. The processing efficiency is availability improved. In this paper introduced:1) The research meaning of the mould structural surface polishing processing based on flexible liquid-solid two phase abrasive flow is introduced. The research situation at home or abroad is gathered up. And the mould structural surface polishing processing based on flexible liquid-solid two phase abrasive flow is brought forward while the principle of this method is analyzed. Based on the principle, the experiment platform and the restricted module are designed and processed.2) Then the control equation is given. Design the rectangle path in the restricted module while a series of Fluent emulation the rectangle paths and the pipes are worked out, including the analyze of the pressure field, the emulation of the speed field and the numerical simulation of different flow passage. The abrasive grains are dynamics analyzed systematic.3) Finally, a series of proof experiments are done using the platform and restricted module which shows the principle of this method is right and the polishing processing method is useful. 9 groups of technologic experiments based on the orthogonal experiments method are done. Working on the results of these experiments, the curve charts showing the influences of the top system impulse pressure P, the polishing time T, and the flow rate qv to the processing effect are worked out. The influence level of the 3 elements to the effect of polishing goes to: the top system impulse pressure P> the polishing time T> the flow rate qv. From assembling the best experiment condition shows: the larger top system impulse pressure, the longer polishing time and the bigger flow rate, the better experiment result. The experience formula is worked out.更多还原