基于响应曲面法的YG8硬质合金刀片化学机械抛光工艺参数优化

为了快速确定YG8前刀面抛光的最佳工艺参数,提高加工效率和精度,利用响应曲面法对YG8硬质合金刀片抛光工艺进行优化试验研究。通过单因素试验确定抛光转速、抛光压力、磨粒粒径和磨粒浓度的水平,并对4个工艺参数进行中心复合设计试验。建立了材料去除率RMR和表面粗糙度Ra的预测模型,基于响应曲面法优化工艺参数获得最佳工艺参数为抛光转速65.5 r/min、抛光压力156.7 kPa、磨粒粒径1.1 μm、磨粒浓度14%,此时得到了最小表面粗糙度预测值Ra=0.019 μm,材料去除率RMR=56.6 nm/min。试验结果表明,基于响应曲面法的材料去除率与表面粗糙度预测模型准确有效。     

螺旋锥齿轮超声研磨加工的机理与实验研究

提出了超声研磨加工螺旋锥齿轮的理论与方法,利用声弹性理论分析了超声波在齿面传播与反射的机理。超声研齿的材料去除以塑性流动去除为主,机理可归结为磨粒锤击微切削、弹跳冲击与研磨液空化效应。试验证明,超声研齿的材料去除率为普通研齿加工的3倍,且齿面质量明显提高,齿面粗糙度Ra为0.2μm,水平截距c为1.2μm。最优工艺参数组合中转矩为0.12 N.m、转速为600 r/m in、研磨剂浓度为20%,其中转矩对材料去除率的影响最为显著,达到68.11%;其次为转速。对最优工艺参数组合所作的验证试验,材料去除率MRR指标与预测值基本相符。     

新型环保抛光液的制备及其对软脆碲锌镉晶片的化学机械抛光

针对软脆碲锌镉晶片的传统加工工艺“游离磨料-抛光-化学机械抛光”存在的缺点,提出“固结磨料研磨-新型绿色环保抛光液化学机械抛光”新方法。固结磨料研磨工艺为：采用3000号刚玉防水砂纸,压力为17kPa,抛光盘与抛光垫转速均为80r/min,研磨时间为5min。新型绿色环保抛光液含有双氧水和硅溶胶,采用天然桔子汁作为pH值调节剂。化学机械抛光工艺为:采用自行研制的化学机械抛光液,绒毛抛光垫,抛光压力为28kPa,抛光盘与抛光垫转速均为60r/min,抛光时间为30min。试验结果表明,经过上述加工可获得超光滑的表面,表面粗糙度算术平均值、均方根值、峰谷值分别可以达到0.568nm、0.724nm、6.061nm。     

集群磁流变变间隙动压平坦化加工试验研究

为了提高光电晶片集群磁流变平坦化加工效果,提出集群磁流变变间隙动压平坦化加工方法,探究各工艺参数对加工效果的影响规律。以蓝宝石晶片为研究对象开展了集群磁流变变间隙动压平坦化加工和集群磁流变抛光对比试验,通过检测加工表面粗糙度、材料去除率,观测加工表面形貌、集群磁流变抛光垫中磁链串受动态挤压前后形态变化,研究挤压幅值、工件盘转速、挤压频率以及最小加工间隙等工艺参数对加工效果的影响规律。试验结果表明：集群磁流变平坦化加工在施加工件轴向微幅低频振动后,集群磁流变抛光垫中形成的磁链串更粗壮,不但使其沿工件的径向流动实现磨粒动态更新、促使加工界面内有效磨粒数增多,而且在工件与抛光盘之间的加工间隙产生动态抛光压力、使磨粒与加工表面划擦过程柔和微量化,形成了提高材料去除效率、降低加工表面粗糙度的机制。对于2英寸蓝宝石晶电（1英寸=2.54 cm）集群磁流变变间隙动压平坦化加工与集群磁流变抛光加工效果相比,材料去除率提高19.5%,表面粗糙度降低了42.96%,在挤压振动频率1 Hz、最小加工间隙1 mm、挤压幅值0.5 mm、工件盘转速500 r/min的工艺参数下进行抛光可获得表面粗糙度为Ra0.45 nm的超光滑表面,材料去除率达到3.28 nm/min。证明了集群磁流变变间隙动压平坦化加工方法可行有效。     

微通道反应器沟槽底面的磨料水射流抛光研究

针对燃料电池微通道反应器的沟槽底面抛光技术难题,开展磨料水射流沟槽抛光仿真与试验研究.采用FLUENT软件,对不同工艺参数下沟槽底部剪切力分布进行了数值模拟;根据仿真结果进行316L不锈钢材料的单沟槽抛光工艺试验,检测分析不同抛光参数下单沟槽底面形貌、材料去除率以及表面粗糙度的变化规律;根据单沟槽底面几何精度和表面粗糙...     

A study on the magneto-assisted spiral polishing on the inner wall of the bore with magnetic hot melt adhesive particles (MHMA particles)

The spiral polishing mechanism employed a fast turning screw rod to drive the abrasive for workpiece surface polishing. In this study, the powerful ring magnet installed around the workpiece would attract the self-developed magnetic hot melt adhesive particles (MHMA particles) during the process of polishing, driving the SiC particles against the workpiece, the inner wall of the bore. At the same time, the flexibility of MHMA particles helped improve the surface quality of the bore by preventing the SiC particles from heavily scratching it. The effects of magnetic flux density, size and concentration of SiC particles, concentration of MHMA particles, viscosity of silicone oil, revolution speed of the spindle as well as machining time and machining gap on operation temperature, slurry viscosity, surface roughness, and material removal were discussed and the best parameter combination was identified based on the results of the experiment. The effects of each machining parameter on the finished surface topography of the workpiece were also examined. Both analysis of variance and F-test indicated that magnetic flux density and the concentration of MHMA particles were the two most important variables affecting the surface roughness. In other words, magnetic force helped improve spiral polishing. Furthermore, the results showed that adding new MHMA particles to the slurry greatly improved the surface quality, at a rate of 90 %, and reduced the workpiece surface roughness from 0.9 μm down to 0.094 μm.     

超薄石英晶片超精密抛光实验的研究

为了解决超薄石英晶片高表面质量的加工问题,以及寻求一种高效低成本的加工方法,将一种新的超精密抛光工艺应用到超薄石英晶片的加工中。给出了加工过程中的抛光原理,制定出了在研磨和抛光过程中的最优实验条件,并对加工后超薄石英晶片的粗糙度和厚度做了详细的分析;讨论了磨粒的尺寸对表面粗糙度和材料去除率的影响,同时对加工过程的材料去除机理做了论述,以表面粗糙度和厚度为评价目标对超薄石英晶片的加工特性和表面质量进行了评价。研究结果表明：使用该实验的工艺加工超薄石英晶片可以得到厚度为99．4μm、表面粗糙度为0．82nm的超光滑表面;同时,该研究还发现通过延长抛光时间可以减小石英晶片的表面残余应力,可有效控制石英晶片四角“翘曲”现象,得到更好的平面度和平行度。     

研磨压力对固结聚集体磨料垫自修正影响

固结磨料研磨过程中磨料的微破碎是实现固结磨料垫自修正特性的主要途径,研磨压力是影响磨粒微破碎的关键参数。选用单晶金刚石和聚集体金刚石作为磨粒制备固结磨料垫,在15 kPa压力下以石英玻璃为加工对象进行研磨实验,比较两者的材料去除率及加工稳定性;制备了4种陶瓷结合剂含量的聚集体金刚石,并制备成固结聚集体金刚石磨料垫,探索了不同压力下的固结聚集体金刚石磨料垫的自修正性能;分析了研磨后的工件表面粗糙度和表面微观形貌。结果表明:采用固结聚集体金刚石磨料垫,研磨后工件表面粗糙度低,去除效率稳定;在15~21 kPa的压力下,结合剂含量次高的聚集体金刚石研磨效率高,材料去除率达到8.94~12.43μm/min,加工性能较稳定,研磨后的工件表面粗糙度R a在60 nm左右;在3.5~7 kPa压力下,结合剂含量次低的聚集体金刚石研磨性能较稳定,材料去除率在2.67~3.12μm/min,研磨后的表面粗糙度R a在40 nm左右。高结合剂含量的聚集体金刚石磨粒更适合高研磨压力条件,而低结合剂的聚集体金刚石磨粒更适合于低研磨压力。     

Effect of machining characteristics on polishing ceramic blocks

In this study, experiments were conducted to examine the effects of polishing parameters such as polishing time, load, rotational speed, diamond size, and concentration when polishing ceramic blocks. It was shown that the material removal rate rises with the increase in polishing time from 20 to 30 min, but drops with the increase from 30 to 40 min. The material removal rate increases with an increase in the load, rotational speed, diamond size, and concentration, respectively. Within the range examined, the surface roughness improves with a longer polishing time, higher rotational speed, smaller diamond size, and lower concentration. The parallelism is highly dependent on the material removal rate. Three main failure mechanisms: cracks, deep pits, and fractures were observed.     

单晶硅同质互抛实验研究

以材料的去除率和表面粗糙度为评价指标设计对比实验,验证了硬脆材料互抛抛光的可行性,得到了抛光盘转速对硬脆材料互抛的影响趋势和大小。实验结果表明：当抛光压力为48 265 Pa（7 psi）、抛光盘转速为70 r/min时,自配抛光液互抛的材料去除率为672.1 nm/min,表面粗糙度为4.9 nm,与传统化学机械抛光方式的抛光效果相近,验证了硬脆材料同质互抛方式是完全可行的;互抛抛光液中可不添加磨料,这改进了传统抛光液的成分;采用抛光液互抛时,材料去除率随着抛光盘转速的增大呈现先增大后减小的趋势,硅片的表面粗糙度随着抛光盘转速的增大呈先减小后增大的趋势。     

光纤端面研磨加工机理研究

给出了研磨光纤时的材料去除机理,选用粒度为微米及亚微米级的金刚石磨料砂纸,在研磨压力为0.48Mpa时,在KE-OFP-12型光纤连接器研磨机上对光纤端面进行了研磨实验.结果表明:光纤研磨加工的材料去除存在脆性断裂、半脆性半延性、延性等3种模式.材料去除模式主要取决于磨料的平均粒度,磨料粒度为3μm时,为脆性断裂到延性研磨的临界转换点.并从理论上对结果进行了分析,光纤以延性模式研磨加工时,光纤表面粗糙度Ra可达到纳米级,其表面看不到任何划痕,而光纤以脆性断裂模式研磨加工时,其表面粗糙度只能达到亚微米级,证明材料以延性模式去除是提高光纤表面质量的有效方法.     

Surface roughness and material removal rate of lapping process on ceramics

Lapping is a widely used surface finishing process for ceramics. An experimental investigation is conducted into the lapping of alumina, Ni−Zn ferrite and sodium silicate glass using SiC abrasive to study the effect of process parameters, such as abrasive particle size, lapping pressure, and abrasive concentration, on the surface roughness and material removal rate during lapping. A simple model is developed based on the indentation fracture and abrasive particle distribution in the slurry to explain various aspects of the lapping process. The model provides predictions for the surface roughness,R _a andR _t , on the machined surface and rough estimation for the material removal rate during lapping. Comparison of the predictions with the experimental measurements reveals same order of magnitude accuracy.     

基于灰色关联度分析响应面法的橡胶软模端面抛磨表面粗糙度预测

为解决复合材料加筋壁板上筋条与蒙皮配合间隙不均匀的问题,需在刚模表面上粘贴橡胶软模,并通过抛磨橡胶软模来消除配合间隙,然而,若打磨参数选择不当,则橡胶软模表面易起毛,致使粗糙度值过大,易吸附磨屑粉尘。针对上述问题,搭建了一套基于机器人的橡胶材料除尘端面打磨系统,探究了磨粒粒度、磨头转速、打磨压力、离边距离等打磨参数对表面粗糙度的影响规律。提出一种基于灰色关联度分析响应面法的机器人橡胶垫抛磨表面粗糙度预测方法,建立了橡胶材料打磨后粗糙度Ra值的预测模型,该模型的拟合系数R2值为0.9878,表明模型拟合效果好。使用该模型计算出的Ra预测值与观测值的均方根误差为0.014 47,验证了模型预测的有效性。基于预测模型,获得粗糙度Ra值最小（3.3 μm）的参数组合为：磨头转速4158.9 r/min、抛磨压力38.4 N、离边距离30 mm。     

研磨工艺对工件表面粗糙度及残余应力的影响

通过试验探讨了研磨过程中磨料粒度、研磨压力和研磨速度等工艺参数对工件表面粗糙度及残余应力的影响。试验结果表明,磨料粒度和研磨压力对工件表面粗糙度的影响较大,而研磨速度的影响较小;研磨使工件表面产生残余压应力,日残余压应力随磨料粒度、研磨压力及研磨速度的增大而增大。     

硬盘巨磁电阻磁头的超精密抛光工艺

硬盘巨磁电阻磁头的抛光可分为自由磨粒抛光和纳米研磨,在自由磨粒抛光中,精确控制载荷和金刚石磨粒的粒径,可以避免脆性去除实现延性去除。通过控制抛光过程中的抛光盘表面粗糙度、金刚石粒径大小及粒径分布和载荷等进行滚动磨粒和滑动磨粒比例的调控,获得较好的磁头表面质量和较高的材料去除率。在自由磨粒抛光阶段,先采用铅磨盘抛光,然后用锡磨盘抛光,以纳米研磨作为最后一道抛光工序对磁头表面进行研磨,获得了亚纳米级粗糙度的磁头表面。用两种工艺制作的纳米研磨盘进行加工,分别获得了0.37nm和0.8nm的磁头表面粗糙度,去除率分别为5.3 nm/min和3.9nm/min。     

精细雾化抛光TC4钛合金抛光液优化研究*

配制适用于TC4钛合金雾化施液抛光的特种抛光液,通过抛光实验获得纳米级的光滑钛合金表面。研究不同磨料、氧化剂和络合剂含量对钛合金材料去除率和表面粗糙度的影响,通过正交试验优化抛光液组成及配比。优化后的抛光液由质量分数20%的SiO2磨料、0.1%的柠檬酸、1%的聚乙二醇-400、2%的H2O2组成,pH值为4。抛光试验结果表明,优化后抛光液的抛光效果较好,材料去除率及试件表面质量均有所提升,其中材料去除率为549.87nm/min,表面粗糙度为0.678 nm。XPS分析表明,抛光过程中钛合金表层在酸性环境下与H2O2和柠檬酸反应,生成了易于通过机械作用去除的氧化层。     

The use of reliability in the Taguchi method for the optimisation of the polishing ceramic gauge block

This paper discusses the optimal parameters using the Taguchi method, but also analyses the Weibull modulus through reliability engineering for polishing ceramic gauge blocks. The optimal polishing parameters for removal rate thus obtained include highest speed, greatest load and a diamond particle size of 3 μm and 30% concentration. The analysis of variance shows that the most significant polishing parameters for removal rate are speed (39.8%) and load (39.2%), followed by concentration (17.9%) and diamond size (3.1%). The optimal polishing parameters for the Weibull modulus are found to be low speed and medium or high load, regardless of diamond size and concentration.     

Prediction of the surface roughness and material removal rate in chemical mechanical polishing of single-crystal SiC via a back-propagation neural network

Chemical mechanical polishing (CMP) is a common method for realising the global planarisation and polishing of single-crystal SiC and other semiconductor substrates. The strong oxidant hydroxyl radicals (·OH) generated by the Fenton reaction can effectively oxidise and corrode the SiC substrate, and are thus used to improve the material removal rate (MRR) and surface roughness (Ra) after polishing of SiC during CMP. Therefore, it is necessary to study the material removal mechanism in detail. Based on the modified Preston equation, the effects of the CMP process parameters on the MRR and Ra after polishing of SiC and their relationship were studied, and a prediction model of the CMP process parameters, MRR, and Ra after polishing was also established based on a back-propagation neural network. The MRR initially increased and then decreased, and the Ra after polishing initially decreased and then increased, with increasing FeSO₄ concentration, H₂O₂ concentration, and pH value. The MRR continuously increased with increasing abrasive particle size, abrasive concentration, polishing pressure, and polishing speed. However, the Ra continuously decreased with increasing abrasive particle size and abrasive concentration, increased with increasing polishing pressure, and initially decreased and then increased with increasing polishing speed. The established prediction model could accurately predict the relationship between the process parameters, MRR and Ra after polishing in CMP (relative prediction error of less than 10%), which could provide a theoretical basis for CMP of SiC.     

SrTiO3陶瓷基片集群磁流变研磨加工表面特性研究

采用集群磁流变效应研磨加工工艺进行SrTiO3陶瓷基片研磨加工,分析了研磨盘材料、磨粒种类、研磨压力和磨粒团聚等因素对SrTiO3陶瓷基片表面粗糙度和表面完整性的影响。 结果表明:磁流变效应研磨工作液中的SiC、Al2O3和CeO2等磨料的大尺寸磨粒在SrTiO3陶瓷基片研磨加工表面产生的局部大尺寸划痕破坏了加工表面的完整性;采用铸铁研磨盘和SiO2磨料的磁流变研磨工作液研磨加工后,原始表面粗糙度Ra从约1.7854μm下降到0.6282μm,并且表面完整,SrTiO3材料与SiO2磨料之间存在的化学机械研磨过程促进了研磨加工表面性能的改善;研磨压力也是影响研磨加工表面粗糙度和大尺寸划痕的主要因素之一,研磨压力取较小值(1.875kPa）为宜。      

Effect of LBM and large-area EBM finishing on micro-injection moulding surfaces

Micro-injection moulding is an efficient process for large series production of thermoplastic polymer micro-parts. The moulding surface quality in the moulds is important and determines the manufacturing specifications for a given micro-engineering component. In this study, melting and vaporisation removal technologies were analysed: laser beam machining (LBM) as the material removal technique and electron beam machining (EBM) as the finishing process. Stainless steel DIN X42Cr13 was used for machining 10?×?10?mm² flat surfaces. LBM parameters, namely intensity, frequency, cutting depth, scanning speed and hatching, and EBM conditions, as energy density, number of irradiation and frequency, were varied. The surface topography and integrity and the micro-structure were characterised by optical and electronic microscopy, roughness profilometry, X-ray spectroscopy and micro- and ultrahardness tests. It was shown that the combination of LBM and large-area EBM is an interesting alternative to polishing by hand lapping of moulding surfaces for micro-moulding, improving surface roughness and surface integrity without cracks and smaller HAZ. The morphology analysis demonstrated that EBM finishing improves corrosion and oxidation resistance compared with conventional heat-treated surfaces.