超精密平面研磨加工速度对精度的影响

为了提高加工精度和减少研磨轮磨损,对研磨加工过程中的加工参数进行分析.针对目前常用的两种不同结构砂轮(放射线研磨轮以及螺旋线研磨轮),采用加工精度系数和砂轮磨损系数的概念描述加工精度与砂轮磨损,并提出相应的数学模型,以分析加工参数与工件精度及研磨轮磨损的关系.着重探讨了研磨轮与工件相对速度变化对加工精度的影响.通过理论分析与实践表明:优化设计砂轮的结构、合理选择加工参数,可以实现提高研磨加工精度及降低砂轮磨损的目的.     

研磨轮结构参数对工件加工精度的影响

通过建立研磨轮和工件的相对运动数学模型，得出研磨轮在工件上的切削运动轨迹方程，由此得到超精密平面研磨中，不同结构参数研磨轮的滑移轨迹长度，引入精度系数的概念，用于评价不同结构参数研磨轮对工件的加工效果，采用微粒金刚石研磨轮对单晶硅和压电陶瓷材料进行研磨实验的结果表明，使用设计合理的研磨轮可以提高研磨的加工精度。     

内圆表面磁性研磨加工的研究

通过对薄壁套筒内表面磁性研磨加工的原理分析和影响加工特性的各种加工因素的实验研究，探讨内表面的最佳磁磨工艺方法，同时表明磁性研磨加工有着十分广阔的应用前景和较主的经济效益。     

柔性磨体振动研磨的原理与应用

本文介绍一种新的研磨加工技术，即柔性磨体振动研磨加工，适用于各类异型截面孔腔，细小沟槽及复杂零件表面的研磨加工，与现有的研磨加工技术相比，有更宽的工艺范围，更高的加工效率，更好的加工表面粗糙度和加工精度，更低的加工成本，该技术有实用价值和推广意义。     

平面磁研磨法的研究：非磁性金属材料的研磨特性和加工机理的考察

利用磁研磨法加工非磁性金属平板的表面时，在通常的磁性磨料中混入大粒径磁性粒子（铁粒子），可以显著提高加工效率。由不锈钢毛病产板的研磨实验中以看到：混入的铁粒子的粒径及其混合比例对加工效率影响很大。在研磨加工中，研磨压力存在最佳值。     

精密零件的大批量研磨工艺

本文介绍用平行砂轮在德国产SLP602S型双盘研磨机上对大批量生产的铁基粉末冶金精密零件进行研磨加工的工艺，并提出了合理的砂轮粒度和硬度、研磨压力、研磨速度及研磨油的技术性能指标，同时给出了适宜于该种研磨加工的砂轮平面度自校正方法。     

球形磁性磨料磁力研磨ZrO2材料机理研究

在磁力研磨加工ZrO 2材料过程中,分析了单颗磁性磨料在加工区域内的受力情况,并对研磨压力的形成进行探讨,利用公式推导计算研磨压力,通过研磨压力的大小分析了磁力光整加工中材料的去除机理,包括脆性断裂去除、塑性变形去除和粉末化去除。通过白光干涉仪、扫描电子显微镜等分析检测仪器对磁力研磨加工后的工件表面进行检测,可知在其他条件相同时,磁力研磨加工后的工件材料精度高于传统的草轮抛光精度,可达到0.59μm。     

磁性磨料研磨加工的实践与研究

本文介绍了磁性磨料研磨的加工原理，不仅对磁极的形状加以分析，还对工件在磁场中的受力情况进行理论分析。对淬硬了的工件外圆进行磁性磨料研磨的加工试验，得出了有轴向振动，无轴向振动，不同的轴向振动频率，以及不同研磨时间对加工表面粗糙度和研磨量的影响；从而得出了优化的磁性磨料研磨的加工参数。对实施实际的磁性磨料研磨的加工有一定的指导和借鉴作用。     

信孚牌特种研磨材料的应用

信孚牌特种研磨材料的应用山西信孚特种磨料有限公司盖耀平我公司生产的信孚牌特种研磨材料是一种新产品，它本身具有的特性使传统的研磨抛光技术变成全新的加工工艺，在机械加工、装配和维修领域有广阔的应用前景。用其他方法无法完成的精密加工，使用该磨料进行研磨和抛...     

磁屏蔽对内圆磁力研磨加工影响的研究

在分析内圆磁力研磨加工原理的基础上，通过适量假设条件的建立，简化了磁力研磨加工区域中的磁场，开利用拉普拉斯方程及必要的边界务件推导出了在磁场中圆柱腔内、外磁感应强度的近似关系，并通过对不同壁厚的45号钢圆柱管的对比试验验证，表明内圆磁力研磨加工只适合加工薄壁磁性材料圆管工件。     

基于无瞬心包络的微细铣刀螺旋槽刃磨分析*

螺旋沟槽属于复杂的空间螺旋面,砂轮与刀具的相对运动复杂,在微细立铣刀的制造过程中耗时最长、难度最大,精确、高效加工螺旋沟槽成为微细铣刀制造过程亟须解决的关键问题之一。基于无瞬心包络原理研究了微细铣刀螺旋沟槽的刃磨过程,提出一种微细螺旋铣刀轴向型线的计算模型,该模型避免了利用接触公法线求解时,因砂轮截形上的奇点和圆滑二次曲线导致无法求解的情况,计算过程与求解简单,适用于对砂轮廓形复杂时刃磨求解。在所建模型基础上分析了砂轮形状和加工参数对螺旋槽型形状的影响,以及砂轮摆角和前刀面宽度对径向前角的影响。通过刃磨验证了模型与分析的正确性,试验证明实际加工的微细铣刀沟槽截形与包络计算的沟槽型线几何形状参数吻合良好。     

点云频域配准的双目双线结构光列车轮对检测

针对单线结构光测量因范围有限以及遮挡等原因而无法检测整个车轮的轮缘及踏面的问题,提出了一种列车轮对双目双线结构光检测方法。该方法采用两组双线结构光传感器进行测量和数据采集。在两传感器产生的点云进行配准的过程中使用截面点云数据还原点云矩阵,然后对其进行傅里叶变换,在计算旋转角度时先进行极坐标转换,最后求取两矩阵的互功率谱,从而得到点云的旋转和平移矩阵。在此过程中考虑到点云噪声的存在,将辛格函数近似代替无噪声的互功率谱傅里叶反变换,从而确定在频域配准时噪声对配准参数的确定并无影响。接着采用相对值比较的算法和主成分分析拟合基准平面,对轮对直径方向进行标定。利用标定值对扫描数据进行处理,得出包括车轮直径、车轮滚动圆径向跳动等对尺寸参数。实验表明:点云频域配准的双目双线轮对检测技术对车轮直径的测量尺寸误差≤±0.05mm,车轮端跳的测量误差≤±0.06mm,车轮径跳的测量误差≤0.04mm。与标准轮对检测数据相比可知,该系统满足轮对检测精度的要求。     

数控成形磨齿机砂轮截形计算

砂轮加工斜齿轮时,斜齿轮齿面法线与砂轮轴线相交。利用这一原理,首先根据斜齿轮方程,计算斜齿轮与砂轮的接触线,求得加工斜齿轮时的砂轮廓形;其次,考虑到实际加工砂轮时金刚轮半径的存在,对砂轮刃形部分和过渡曲线部分分别进行了半径补偿;最后,利用B样条曲线和de boor算法,根据插补步长要求,运用时间分割插补算法,得到金刚轮加工砂轮时的插补点,给出了计算实例,并对砂轮廓形进行了拟合。     

新形蜗杆砂轮无轴向进给磨削圆柱齿轮技术原理

在分析空间相错轴螺旋齿轮传动实现瞬时线接触共轭的条件与方法基础上,新建立了一种齿面直线接触的蜗杆传动方式。提出了以这种蜗杆为砂轮实现无轴向进给磨削圆柱齿轮的原理与方法。论述了运用这种蜗杆原理的双蜗杆磨轮磨削圆柱齿轮的结构实现、磨削进给的实现方法等,并推导了磨削速度计算公式。这种磨削加工方法结构简单、无需轴向进给、相对滑动速度大、效率高,可以用于大批量生产中齿轮的磨削加工或者珩磨加工。     

Surface finishing of flat pieces when submitted to lapping kinematics on abrasive disc dressed under several overlap factors

In machining of pieces that require surface finishing levels finer than grinding can offer, it is necessary to use specific finishing processes. However, these processes, which have lapping as the most classic representative, are usually difficult to setup and demand much time in setting the large number of variables. This paper discusses the investigation of an abrasive process for finishing of flat workpieces based on the combination of important grinding and lapping characteristics. Instead of loosing abrasive grains between the workpiece and the lapping plate, a resinoid grinding wheel of hot-pressed silicon carbide is fixed on the plate of a device resembling to a lapping machine. The grinding wheel is dressed with a single-point diamond for maintaining its form flat and mainly for interfering in the workpieces surface finishing by varying of the overlap factor (Ud). It was noticed that the studied process can simplify the setup and make it easier than in lapping, which is a painstaking process. The surface roughness values and flatness deviations showed to be comparable to those achieved in lapping, or even better. The best surface roughness and flatness deviation found were Ra = 0.8 nm and 0.4 μm with Ud = 3, respectively. The workpiece material was made of quenched and tempered SAE 4340 steel, reaching a hardness of 60 HRC. The process was also monitored by acoustic emission (AE), which indicates to be a promising and suitable technique to be used in this process. Compared to lapping, there is an additional advantage of a less contaminated workpiece surface with a shiny appearance.     

非共轴螺旋后刀面微钻的五轴联动刃磨方法及其钻削性能研究

微细钻头的几何结构是影响刀具钻削性能和微孔加工质量的关键因素。非共轴螺旋面钻尖由连续的螺旋后刀面组成,相比平面钻尖能有效的提高刀具的刃磨效率及其钻削性能。针对非共轴螺旋面钻尖,推导后刀面形成过程中螺旋运动发生线的位置方程,建立了基于砂轮和钻头接触线的后刀面数学模型。根据六轴数控工具磨床的运动原理,提出非共轴螺旋后刀面五轴联动刃磨方法。分析砂轮与螺旋槽之间的相对运动关系,提出微细钻头螺旋槽的数控加工方法。进行非共轴螺旋后刀面微钻的刃磨试验,验证了该刃磨方法的可行性。进而采用制备出的具有相同几何结构参数的平面、锥面和非共轴螺旋面微细钻头进行不锈钢钻削试验,结果表明非共轴螺旋面和锥面微钻的钻削力、后刀面磨损明显小于平面微钻,并且非共轴螺旋后刀面微钻的横刃磨损程度小于平面和锥面微钻。研究证实了所提出的五轴联动刃磨方法可以有效地制备出较高钻削性能的非共轴螺旋后刀面微细钻头。     

Development of a new lapping method for high precision ball screw (1 report)-feasibility study of a prototyped lapping tool for automatic lapping process

Ball screws are being lapped as a finishing process to improve the travel variation, drunkenness and surface finish in order to provide high precision requirements in various mechanical applications. However, the existing manufacturing method is very labor intensive that needs a highly skilled machinist to perform the hand lapping operations using the conventional laps which have two or three slits. These types of lap cannot eliminate and improve the special components of drunkenness such as ellipsoidal, triangular and other polygonal cross sections. This paper presents a new lapping method to determine the technical and operational feasibility of a prototyped lapping tool with the combination of a flexible lap and polyurethane elastomer which can be mounted in the vertical-type automatic lapping machine. This new type lapping tool with six slits, is especially designed which each section can move in radial direction wherein the uniform lapping pressure is applied on the test piece from six directions. Based on experimental results, it showed that the travel variation was greatly reduced along with drunkenness and lapping time.     

Ultra-precision lapping of machinable ceramic Si3N4-BN by in-process electrolytic dressing

The machinable ceramic Si₃N₄-BN is a material which is increasingly being employed for automobile bearings and machinable ceramics. This material is very hard and has high resistance against volatile temperature and wear. It's efficient quality and accurate surfaces have always been of high demand for many applications in the industrial field. Besides, this material is varied by the percentage of BN contained in it, and the characteristics of lapping also varies according to this percentage of BN. Hence, in-process electrolytic dressing for ultra-precision lapping was introduced and used to experiment with the differing BN percentages in machinable ceramic Si₃ N₄. Metal-bonded super-abrasive diamond lapping wheels have superior qualities such as high bond strength, high stability and high machinability. The major problems encountered are wheel loading and glazing, which impedes the effectiveness of the cast-iron bonded diamond lapping wheel and, therefore, dressing should be considered. In this respect, in-process electrolytic dressing (IED) is proposed as an effective method regarding continuous protruding abrasives on the surface of wheels, whereby loading and glazing phenomena can apparently disappear. In this paper, the machining characteristics of machinable ceramic Si₃N₄-BN have been studied by adapting the IED lapping process in terms of the percentage of h-BN material.     

金刚石研磨技术的研究与研磨机的改造

分析了金刚石的研磨技术 ,介绍了金刚石的研磨方法。提出一种研磨机改造方案 ,增强了研磨机的控制功能 ,提高了研磨机的加工精度 ,降低了金刚石刀具的加工成本。