陶瓷加工专用套料钻的研制

简要介绍了工程陶瓷材料的性能;选择了加工方式和工具材料;分析了套料加工原理;讨论了金刚石套料钻的结构及制作工艺,给出了套料钻的主要性能参数。     

钎焊套料钻钻削碳纤维增强复合材料层合板出口撕裂缺陷的成因分析

针对碳纤维增强复合材料钻孔时钻头寿命短、易产生加工缺陷等问题,将钎焊金刚石套料钻应用于碳纤维增强复合材料的钻削加工中。为更好地说明钎焊金刚石套料钻的加工性能,选取了复合材料钻削中常用的金刚石涂层麻花钻进行比较,并选择了实际加工中严重影响加工质量的出口撕裂缺陷进行成因分析。通过检测与分析出口处加工质量,得到以下结论：对于不同结构形式的钻头,仅依靠轴向力及扭矩并不能判断是否产生撕裂缺陷;在相同工艺参数下,钎焊金刚石套料钻的轴向力及扭矩均小于金刚石涂层麻花钻的轴向力及扭矩,使用钎焊金刚石套料钻更有利于减少撕裂缺陷,提高加工效率。     

钎焊金刚石刀具钻削新型复合板试验

为解决新型“三明治”复合层板“凯芙拉复合材料-特种陶瓷-铝合金”孔加工的难题，文中尝试在Z5125立式钻床上采用电镀金刚石套料钻和最新研制的钎焊金刚石套料钻钻削通孔。试验结果表明：电镀金刚石套料钻仅钻削1／2个孔，金刚石磨料就完全脱落；钎焊金刚石套料钻连续钻削10个孔，切削部位无明显变化，加工效率高且孔表面光滑平整，完全满足技术要求，为新型复合材料层板“凯芙拉复合材料-特种陶瓷-铝合金”孔加工寻到了一条方便、经济、有效的新途径。     

C/SiC复合材料钻削工具载荷及磨损研究

采用HAM PCD焊刃麻花钻、KENNA CVD涂层麻花钻、金刚石套料钻(普通钻削与超声辅助钻削两种方法)三种工具对C/Si C复合材料进行了钻削试验,并对工具磨损情况、钻削力及扭矩进行了对比分析。结果表明:累计钻削深度lT=160mm后,套料钻普通钻削、超声辅助钻削磨损程度较轻,而HAM PCD焊刃麻花钻,KENNA CVD涂层麻花钻磨损严重。不同工具钻削加工时钻削力及扭矩随着工艺条件的变化呈现不同的变化趋势;采用套料钻加工时,与普通钻削相比,超声辅助钻削可有效降低钻削力及扭矩,最大降低幅度分别达到23%、56%。整体而言,套料钻超声辅助钻削加工时钻削力及扭矩较小、工具磨损较轻,是一种适合于C/Si C复合材料制孔的工艺方法。     

套料钻的快速刃磨方法

在陶瓷板材上加工通孔时，常采用套料方式。套料钻以人造金刚石与金属粉末为原料烧结制成，使用效果良好，但自锐性差，经过一段时间后，金刚石不出刃，刀具逐步磨钝，需要频繁刃磨。由于套料钻的端面、内外圆等三个表面都承担切削任务，用砂轮磨削或金刚石笔修整，既费时费力，成本又高，特介绍一种刃磨该类刀具的简单方法。     

金刚石套料刀

金刚石套料刀的试制成功改变了电子、光学工业部门历来采用的极为落后的散砂工艺套料半导仕、光学玻狱的加::八沙。经有关单位使用鉴定,金刚石套料刀用作必17'1毫米的硅片套料仅4c秒nIl可套料一片,提高工效叨倍     

永磁材料套孔加工轴向进给力经验公式的建立

钕－铁－硼永磁材料的性能优于所有传统永磁体材料，它可使仪器仪表电子设备的元器件微型化，具有广阔的发展前景。钕－铁－硼永磁材料比较昂贵，为节约原材料，加工时应尽可能减小去除量，尤其是进行孔加工时，应采用套孔加工，芯柱可留作他用。用套料刀具在实心材料上环形切割称为套孔加工，套孔与钻孔相比不仅能减少轴向载荷，提高生产效率，而且能减少材料的损耗。用金刚石工具加工钕－铁－硼永磁材料是一种十分有效的加工方法。刀具结构如图所示。刀头上电镀金刚石并开有４个槽，在套孔时整个刀具的端面都参与切削，轴向抗力与工具的轴…     

镍铁合金电沉积金刚石工具的研制

提出了采用镍铁合金作为电沉积金刚石工具结合剂的构想。通过分析研究 ,确立了工艺方案 ,对影响镍铁合金沉积层质量的主要因素进行了分析 ,优化了底层沉积、上砂沉积以及加厚沉积时的镀液温度、阴极电流密度等。金刚石套料钻的研制成功 ,证实了镍铁合金作为电沉积工具结合剂的可行性。     

工程陶瓷材料孔加工技术的试验

立足于传统加工方法 ,考虑加工的经济性、实用性和易操作性 ,采用新研制的单层高温钎焊金刚石套料钻及专用钻套夹具对工程陶瓷材料进行了钻孔加工试验 ,试验结果表明 ,该工艺方法可高效、简便地加工出高质量的陶瓷孔 ,具有实用和推广价值。     

方舱用工程陶瓷材料孔加工技术的试验研究

从加工的经济性、实用性和易操作性考虑,立足于传统加工方法,采用了最新研制的单层高温钎焊金刚石套料钻,设计了专用夹具,对工程陶瓷进行了钻孔加工试验。试验结果表明,这种工艺方法可以高效简便地加工出较高质量的陶瓷孔,具有实用和推广价值。     

Nd-Fe-B烧结永磁体材料的超声加工机理

对Nd-Fe-B烧结永磁体材料超声振动加工过程中的材料去处机理进行了理论研究,研究结果对实际生产具有一定的指导作用,并进行了加工实验研究。     

Nd-Fe-B烧结永磁材料的车削加工研究

对Nd-Fe-B烧结永磁材料的车削加工进行了试验研究。用线性断裂力学的方法建立了硬脆材料车削加工时的材料去除模型。探讨了车削过程中背吃刀量、进给量和车削速度对车削力及加工表面质量的影响，采用多元回归分析方法得出了主车削力的经验公式，并给出了用于检验回归结果与试验结果符合程度的误差评判参数。分析了Nd-Fe-B烧结永磁材料车削过程中刀具的磨损状况，以及刀具几何参数对加工质量的影响。     

A comparative study of material phase effects on micro-machinability of multiphase materials

In the mechanical micro-machining of multiphase materials, the cutting process is undertaken at a length scale where material heterogeneity has to be considered. This has led to increasing interest in optimising the process parameters for micro-machining of such materials. In this study the micro-machinability of two steels, a predominantly ferrite material (AISI 1005) and a near-balanced ferrite/pearlite microstructure (AISI 1045) was studied. Workpiece sample deformation properties were characterised by nano-indentation testing. Additionally, metallographic grain size evaluation was undertaken for the workpiece microstructures. Surface roughness, workpiece microstructure and burr size for micro-machined parts as well as tool wear were examined over a range of feed rates. The results suggest that for micro-machined parts, differential elastic recovery between phases leads to higher surface roughness when the surface quality of micro-machined multiphase phase material is compared to that of single phase material. On the other hand, for single phase predominantly ferritic materials, reducing burr size and tool wear are major challenges. Thus, the paper elucidates on material property effects on surface and workpiece edge quality during micro-milling.     

烧结钕-铁-硼永磁材料的研究进展

钕-铁-硼磁体被称为第三代稀土永磁材料,烧结钕-铁-硼磁体是目前综合磁性能最高的永磁材料。介绍了烧结钕-铁-硼磁体的研究现状、应用领域,阐述了烧结钕-铁-硼磁体的有关理论及先进生产工艺的特点,重点分析了低氧湿压、片铸、放电等离子烧结等工艺的特点,指出了目前国内烧结钕-铁-硼磁体存在的主要问题及今后的研究方向。     

电化学磁粒光整加工实验

从电化学磁粒光整加工对材料去除量和表面粗糙度影响规律的实验结果表明,由于磁粒加工过程中不断地去除钝化膜,使表面露出的新基体,从而进一步加速了电化学过程,实现表面整平,磁粒光整加工和电化学过程的复合,使光整加工效率和表面质量得到提高。     

The coupled effect of magnetic field,electric field,and electrolyte motion on the material removal amount in electrochemical machining

Electrochemical machining (ECM) has a strong advantage in dealing with difficult-to-machine materials and complex shaped parts. In order to improve machining accuracy, some researchers, based on the principle of interactions between the magnetic field and electric field, proposed the magnetic field-assisted ECM technology that is advantageous in improving surface roughness and facilitating material removal amount. Pitifully, little attention has been attached to effects of the coupled magnetic field, electric field, and electrolyte motion on the amount of materials removed. This paper aims to find out how arrangements of magnetic fields and coupled of the three energy (which were magnetic field, electric field, and electrolyte motion) will work on the amount of material removed in ECM. Here established a Navier-Stokes equation and a model of material removal amount in the anode under the electromagnetic field. Physical and mathematical models of the electrolyte’s flow characteristics and material removal amount were constructed through the COMSOL Multiphysics software, and simulations were carried out. An experiment was implemented to test models and the simulations. Simulation results indicated that different arrangements of the magnetic field had delivered different impacts on flow characteristics of the flow field and material removal amount. Experiment results revealed that the material removal amount had increased regardless of arrangements of magnetic fields and that the flow rate of the electrolyte had played a role in this connection. The study involved in this paper showed that the introduction of the magnetic field worked favorably to lift the material removal amount and that arrangements of magnetic fields also had the same effect in this regard. Also, it was found that a growing flow rate of the electrolyte had hindered the increases of the material removal amount.     

超磁致伸缩超声振动系统的机电转换效率研究

为提高超声振动系统的能量转换效率和功率容量,提出超磁致伸缩超声振动系统的设计方法,研究导磁体材料特性对超声系统振动性能的影响规律。采用硅钢、铁氧体和磁粉心三种磁性材料设计导磁体,并建立超声振动系统的等效电路模型;通过阻抗分析建立3种超声振动系统的阻抗圆曲线,得到谐振频率和机电转换系数等参数,提出导磁材料特性对系统机电能量转换效率的影响规律。为验证阻抗分析结果的正确性,试验测定3种超声系统在不同电压幅值激励下的振幅-电流灵敏度与频率的关系曲线,验证导磁材料参数与系统机电能量转换效率之间的关系。结果表明：高磁导率铁氧体材料可提高超声振动系统在小功率工作条件下的机电能量转换效率,而对于大功率超声振动系统而言,需要兼顾磁导率和饱和磁通密度,使导磁体工作于非磁饱和状态,以提高系统换能效率,这有助于指导不同功率大小超声振动系统的导磁体材料选择。     

Examination and Research of the Surface Topography of Ultrasonic Vibration Honing Nd-Fe-B

The mechanism of ultrasonic vibration honing Nd-Fe-B has been briefly elaborated after the introduction of the strategic significanoe of processing Nd-Fe-B.Based on the formation principle of Scanning Electrvnic NTicroscope (SFM),and at the exarrnination with the aid of SEM to the ultrasonic vibration honing Nd-Fe-B materials superficial microscopic topography,the paper discusses the new processing mechanism according to the SFM examination picture.The research indicates that as a result of supersonic high frequency vibration,the path of the abrasion extends at the same time,and the supersonic cavitation effect fonts the intense shock-wave,impacting Nd-Fe-B material's internal surface,providing the supersonic energy for the superficial abrasive dust's elimination,which directly explain tat the honing processing efficiency is entranced,and the processing surface rwghness is high.     

Precision Grinding of Mn-Zn Ferrite with In-Process Electro-Discharge Dressing

Ferrite is widely used as a material for magnetic heads for hard disks, but it is difficult to grind because its high hardness and brittleness. Therefore, a superabrasive diamond wheel is used for precision surface grinding of this material. However, the conventional dressing method cannot be applied to a superabrasive diamond wheel. This study describes a new method for carrying out effective in-process electro-discharge dressing (IEDD) of a superabrasive diamond wheel. Using IEDD, the surface roughness of the Mn-Zn ferrite was improved, and the grinding force was reduced. IEDD is a good method for obtaining efficient surface grinding of ferrite.     

超声磁力复合研磨钛合金锥孔的试验研究

为了提高钛合金锥孔的研磨质量和研磨效率,提出了采用超声波振动辅助磁力研磨的复合加工方案。加工时,磨粒在磁场束缚下切削锥孔表面,并对其进行不断撞击,且因为磁场力、超声振动力和离心力等综合影响的原因,磨粒的切削轨迹呈现明显的多向性。针对钛合金锥孔,与传统磁力研磨法进行试验对比,并分析研磨后试件的材料去除量、表面粗糙度和表面形貌等来验证超声磁力复合研磨的效果。结果表明：超声磁力复合研磨加工效率得到提高;锥孔的材料去除量增加至1.6倍;研磨后锥孔平均表面粗糙度由原始的R_a1.23 μm降至R_a0.25 μm,下降率是传统工艺的1.3倍;试件表面的微波峰、凹坑和加工纹理均被去除,锥孔表面质量得到显著提高,且试件形状精度得到改善。