摘要
为解决SiC/Al功能梯度材料在混粉电火花加工工作液中固体粉末颗粒分布不均匀的问题,建立了搅拌装置的三维模型及搅拌槽内固体粉末颗粒运动的数学模型,利用Fluent软件完成了对搅拌装置内部混粉工作液的流场及其固液悬浮特性的仿真分析,模拟了搅拌装置内部混粉工作液的流场、固体粉末颗粒及湍动能的分布情况,研究了搅拌槽的槽型、深径比、桨叶设计角度、桨叶安装高度以及固体粉末颗粒的体积分数对其影响规律,另外对混粉电火花加工设备中搅拌槽的结构及尺寸进行了优化。采用深径比为0.8、桨叶设计角为45°、桨叶安装高度为120 mm的球底搅拌槽,固体粉末颗粒的悬浮均匀性最终达到最优状态。Al粉末浓度为4 g·L^-1、脉宽为175μs、脉间为75μs时,进行了SiC/Al功能梯度材料常规与混粉电火花加工对比试验。结果表明:采用混粉电火花加工,与常规电火花加工相比,效率提高了16.34%,表面粗糙度降低了27.28%,为实际生产中高效、高质量地加工SiC/Al功能梯度材料提供了理论依据和实验依据。
In order to solve the problem of non-uniform distribution of the solid powder particles in the electrical discharge machining(EDM)working fluid during the powder mixed EDM of SiC/Al functional gradient material,the three-dimensional model of the stirring device and the mathematical model of the powder particle movement in the stirring tank were established.The simulation and research of the internal flow field and solid-liquid suspension characteristics of the stirring tank were carried out by Fluent.The distribution of the flow field,solid powder particles and the turbulent kinetic energy in the stirring tank was simulated.And the effects of the groove type,the depth-to-diameter ratio,the design angle of the blade,the installation height of the blade and the volume fraction of the solid powder particles were studied.In addition,the structure and size of the stirring tank in the powder mixed EDM equipment were optimized.When the depth-to-diameter ratio of the spherical stirring tank was 0.8,the design angle of the blade was 45°and the installation height of the blade was 120 mm,the suspension uniformity of solid powder particles was the best.Using the stirring device,a comparative test of SiC/Al functional gradient material about the powder mixed EDM and the conventional EDM was carried out when Al powder concentration is 4 g·L^-1,pulse width is 175μs and pulse interval is 75μs.Compared with the conventional EDM,the efficiency of the powder mixed EDM increased by 16.34%and the surface roughness decreased by 27.28%.Therefore,theoretical and experimental basis is provided in practice for the high-efficiency and high-quality processing of SiC/Al functional gradient materials.
作者
冀蕴
唐霖
张新运
任磊
JI Yun;TANG Lin;ZHANG Xinyun;REN Lei(School of Mechatronic Engineering,Xi’an Technological University,Xi’an 710021,China)
出处
《西安工业大学学报》
CAS
2020年第6期605-616,共12页
Journal of Xi’an Technological University
基金
国家自然科学基金项目(51405365)
陕西省自然科学基础研究计划项目(2019JM-579)
陕西省教育厅服务地方专项产业化计划项目(17JF010)。
关键词
SiC/Al功能梯度材料
混粉电火花加工
搅拌装置
固液悬浮特性
SiC/Al functional gradient material
powder mixed electrical discharge machining
stirring device
solid-liquid suspension characteristic
