磁性复合流体的深孔抛光工艺试验研究

针对深孔零件光整加工技术的难题,提出了基于针式抛光头的磁性复合流体（MCF）深孔抛光的加工方法。首先利用COMSOL Multiphysics有限元软件建立不同的永磁铁磁场组合模型,根据仿真结果设计磁场分布均匀且强度较强的针式抛光头;再建立MCF深孔抛光的磁流场耦合模型,分析MCF的流动特性;以黄铜H62的深孔零件为加...     

磁场电化学光整加工研究

建立了磁场电化学光整加工中离子运动轨迹方程,通过旁通分析了磁场对光整加工的作用及整平机制。研究结果表明：（１）磁场活跃了离子运动轨迹,改变了离子到达试件表面的方式,从而改善了表面粗糙度;（２）磁场的搅拌作用,加强了液相对流,离子的扩散和迁移,改变了电化学反应,使极间电流强度增大,加工效率提高;（３）磁场、电场和电极间隙存在最佳匹配关系。     

微沟槽周期结构表面的磁性复合流体微纳光整研究及实验教学装置应用

针对磁性复合流体黏度可控的特性,研究一种微纳沟槽表面可控抛光加工方法及工艺,实现低成本、可控微纳结构表面加工技术,并将其应用于微纳加工实验教学。采用磁性复合流体作为抛光液,设计端面式和圆周面式两种磁性复合流体抛光机构;根据周期性微米级沟槽表面结构特点,采用圆周面式磁性复合流体抛光机构进行微结构表面抛光加工实验;设计加工工艺,通过实验对比微沟槽周期结构表面加工效果,验证了实验装置及微结构可控抛光加工方法的有效性,实现微沟槽周期结构表面材料可控去除加工。该装置结构紧凑,使用与维护成本低,有效填补面向机械专业制造类课程的微纳加工实验教学装置技术空白。     

磁流变抛光头形状对加工表面粗糙度的影响

设计了4种不同形状的抛光头,并使用自制的磁流变抛光液体在三轴数控铣床上对K9平面玻璃进行了磁流变抛光工艺试验.分析了在不同的磁场强度、磁极转速,加工间隙等多种情况下抛光头形状对加工表面粗糙度的影响.试验结果表明:槽型平面抛光头的抛光效果最好;同等条件下,在抛光头上开槽能有效地提高加工效率和加工质量.     

Viscosity behavior of magnetic suspensions in fluid-assisted finishing

Magnetic fluid-assisted finishing has been verified both theoretically and experimentally as an effective fabrication technology for optical mirrors and lenses. The purpose of this paper is to introduce a novel design of polishing tool and demonstrate the possible applications of this technology. The work includes studying the viscosity of the magnetic suspensions of micrometer-sized Carbonyl iron particles under the influence of a magnetic field. Both the cases of magnetizable suspension with and without abrasive cerium oxide particles are studied for their ensuing polishing effectiveness. Determination of material removal function is conducted using a Wyko Nat1100 interferometer. Experiments to reduce surface roughness with the proposed tool are also performed using a K9 mirror as the work-piece. Results show that the surface accuracy is improved over three times to less than 0.5 nm after two cycles of polishing.     

Viscosity behavior of magnetic suspensions in fluid-assisted finishing

Magnetic fluid-assisted finishing has been verified both theoretically and experimentally as an effective fabrication technology for optical mirrors and lenses. The purpose of this paper is to introduce a novel design of polishing tool and demonstrate the possible applications of this technology. The work includes studying the viscosity of the magnetic suspensions of micrometer-sized Carbonyl iron particles under the influence of a magnetic field. Both the cases of magnetizable suspension with and without abrasive cerium oxide particles are studied for their ensuing polishing effectiveness. Determination of material removal function is conducted using a Wyko Nat1100 interferometer. Experiments to reduce surface roughness with the proposed tool are also performed using a K9 mirror as the work-piece. Results show that the surface accuracy is improved over three times to less than 0.5 nm after two cycles of polishing.     

Viscosity behavior of magnetic suspensions in fluid-assisted finishing

Magnetic fluid-assisted finishing has been verified both theoretically and experimentally as an effective fabrication technology for optical mirrors and lenses. The purpose of this paper is to introduce a novel design of polishing tool and demonstrate the possible applications of this technology. The work includes studying the viscosity of the magnetic suspensions of micrometer-sized Carbonyl iron particles under the influence of a magnetic field. Both the cases of magnetizable suspension with and without abrasive cerium oxide particles are studied for their ensuing polishing effectiveness. Determination of material removal function is conducted using a Wyko Nat1100 interferometer. Experiments to reduce surface roughness with the proposed tool are also performed using a K9 mirror as the work-piece. Results show that the surface accuracy is improved over three times to less than 0.5 nm after two cycles of polishing.     

难加工合金材料复杂曲面磁性磨料光整加工技术

磁性磨料光整加工技术是一种非常重要的光整加工技术,与低频振动和超声振动相结合,可实现高精度、高质量和高效率的光整加工。介绍了磁性磨料光整加工、振动辅助磁性磨料光整加工及超声辅助磁性磨料光整加工技术的原理和特点及相关的国内外研究现状。根据难加工合金材料复杂曲面的特点,提出实现复杂曲面磁性磨料光整加工,需要就以下问题开展进一步研究和探索:通过提高加工间隙的磁通量密度及磁能与其他能量复合来提高光整加工效率;建立复杂曲面磁性磨粒光整加工过程控制函数;探讨在磁极工具的空间几何约束作用下复杂曲面磁性磨料光整加工工艺的规划方法等。     

TC4钛合金磁流变抛光的磁感应强度分布及参数

使用磁流变抛光技术对钛合金进行抛光,为了获得更好的表面质量,分别对磁感应强度分布、磁流变液和抛光参数进行了研究。首先,优化了加工区域的磁感应强度分布,通过在加工区域添加两块铁板,磁感应强度分布变得均匀,从而提高抛光后钛合金工件的表面质量。其次,分析了磁流变液的组成,即基液、磨粒类型以及磁性粒子和磨粒的质量占比对工件表面粗糙度的影响。随后,研究了四个基本抛光参数,即磨粒目数、工件转速、磁感应强度和抛光时间,找出这些参数对表面质量的影响规律。采用响应面法获得了工件表面粗糙度变化率的模型,并进行了方差分析以检查模型的显著性。最后,找出最优的抛光参数并对其进行了实验验证。     

具有公自转运动形式的可更新磁流变抛光工具

在光学自由曲面的成形抛光加工当中,加工去除的稳定性对工件加工质量具有重要的影响,而抛光液的更新是保证去除稳定的关键。该文提出了一种具有公自转运动形式的可更新磁流变抛光工具,能够完成磁流变抛光液内部磁链的重组更新,使得加工去除稳定。针对此抛光工具,使用刚体润滑理论获得理论去除轮廓,通过实验获得其在单自转状态下的去除轮廓,与理论分析吻合。峰值去除量时间的实验表明,该抛光头的去除效果受时间的影响很小,抛光去除稳定。     

磁力研磨机理研究

磁力研磨是1种利用磁性磨料和磁场作用进行研磨加工的工艺方法.阐述了磁力研磨的特点,分析了研磨过程中材料的去除机理,研究了磁性磨料、磨粒的受力状况和磁力研磨的磨削原理.     

磁性复合抛光体配制及其抛光性能试验研究

介绍一种新的磁性复合抛光体（MPT）的配制及检测方法．新的磁性抛光体是将磁性复合流体和磨粒、植物纤维素均匀混合,通过外加磁场压缩制成的,在磁场作用下为半固态．MPT的主要成分及规格：煤油基纳米直径Fe3O4的磁流体（MF）、微米级直径的铁粉、微米级直径的纯Al2O3磨粒．对几种混合比例的MPT分别进行了SEM的显微观察和抛光作用力的三维检测,在给定压力下对MPT的剪切力和抛光性能进行了试验．结果表明：磁性复合抛光体的配比影响着MPT最大剪切力,具有承受剪切力大的磁性抛光体的抛光效果较好．该研究为复杂曲面的高效、高质量抛光提供了应用依据．     

Nanoscale electropolishing of high-purity nickel with an ionic liquid

High purity(99.9% composition) nickel metal specimens were used in electropolishing treatments with an acid-free ionic liquid electrolyte prepared from quaternary ammonium salts as a green polishing solution. Voltammetry and chronoamperometry tests were conducted to determine the optimum conditions for electrochemical polishing. Atomic force microscopy(AFM) revealed nanoscale effectiveness of each polishing treatment. Atomic force microscopy provided an overall observation of the material interface between the treated and unpolished regions. Surface morphology comparisons summarized electrochemical polishing efficiency by providing root-mean-square roughness averages before and after electrochemical polishing to reveal a mirror finish six times smoother than the same nickel metal surface prior to electropolishing. This transition manifested in a marked change in root-mean-squared roughness from 112.58 nm to 18.64 nm and producing a smooth mirror finish. Finally, the mechanism of the ionic liquid during electropolishing revealed decomposition of choline in the form of a transient choline radical by acceptance of an electron from the nickel-working electrode to decompose to trimethylamine and ethanol.     

光学元件磁性复合流体抛光特性研究

采用磁性复合流体(MCF)对BK7玻璃进行定点抛光实验,对抛光斑进行三维模型重构,并对磁场空间分布进行仿真与实验分析,阐明抛光材料去除机理,确定材料去除率、表面粗糙度及硬度随抛光时间的变化规律,建立了材料去除量与磁通密度的关系曲线。实验结果表明:抛光形成的抛光斑表面轮廓为蝶形,其沿抛光轮轴向的截面轮廓呈"W"形;材料去除量与磁场强弱及抛光时间密切相关,抛光深度去除率最高可达553 nm/min;表面粗糙度随抛光时间的增加先上升后下降,MCF抛光可获得表面粗糙度Ra6 nm的光滑表面,且粗糙度与硬度呈现一定的正相关关系。     

超声电流变复合抛光试验

针对模具微结构光整加工,利用电流变效应对磨料的聚集作用和超声振动对磨料的驱动作用,提出了超声电流变复合抛光工艺.开发了超声电流变复合抛光加工系统.正交试验结果表明超声振动的振幅和施加的电场强度对表面粗糙度的影响最大.通过单因素试验研究了超声电流变复合抛光工艺参数对抛光后表面粗糙度的影响规律.试验结果验证了超声电流变复合抛光工艺可行性,为后续工艺优化和实际应用奠定了基础.     

磁性研磨的加工特性

磁性研磨是一种利用磁场中的磁性磨料对具有相对运动的工件表面进行光整加工的新技术，具有表面质量好、适应性能广泛的优点。     

脉冲电化学光整加工表面质量的神经网络模型研究

利用神经网络方法研究了脉冲电化学光整加工表面质量与各主要工艺参量之间的复杂非线性关系,建立了二者之间的神经网络预测模型,预测结果与实验结果较为吻合。研究结果表明,神经网络计算用来预测脉冲电化学光整加工的工艺性能是可行的。     

Progress in material removal mechanisms of surface polishing with ultra precision

Chemical mechanical polishing (CMP) process is commonly regarded as the best method for achieving global planarization in the field of surface finishing with ultra-precision. The development of investigation on material removal mechanisms for different materials used in computer hard disk and ultra-large scale integration fabrication are reviewed here. The mechanisms underlying the interaction between the abrasive particles and polished surfaces during CMP are addressed, and some ways to investigate the polishing mechanisms are presented.     

聚氨酯微孔抛光衬垫

研制的抛光衬垫,是一种微孔弹—塑性聚氨酯泡沫制品,在其结构中含有固体的磨料或抛光剂,用快速三步法制备,在机床加工成为图片。 这类抛光村片,成功地用于精密光学镜片和眼镜片的抛光,亦用于合金和其它材料的抛光和精加工。 聚氨酯基体材料和其它聚合物互穿网络,能提高衬片的承载性能。     

镍铬合金钢脉冲电流电化学抛光工艺研究

机械零件的表面质量直接影响其使用寿命.采用电化学机械复合抛光,可以大大提高机械零件的抛光效率,但对于深小孔等抛光工具(磨头)很难深入的小结构,采用此方法工艺上很难实现.脉冲电流电化学抛光可以经济有效地对复杂形状的零件型腔进行抛光.对镍铬合金材料试件进行了脉冲电流电化学抛光的工艺试验,讨论并分析了实验结果,得出了加工参数对表面粗糙度的影响规律,以及各加工参数影响表面粗糙度的经验公式.