抛丸机斗式提升机的设计翻译

1、毕业设计（）英文资料翻译Micro Shot Blasting of Machine Tools学院：西北工业大学明德学院专业：机械设计制造及自动化班级：161003 班姓名：王 志 伟学号：103359指导老师：张 永 红2014 年 6 月Micro shot blasting of machine tools for improving surfacefinish and reducing cutting foranufacturingD.M. Kennedy *, J. Vahey, D. HanneyFaculty of Engineering, Dublin Institute o

2、f Technology, Bolton Street, Dublin 1, IrelandReceived 5 January 2004; accepted 3 February 2004Available online 13 April 2004AbstractMicro blasting of cutting tips and tools is a very effective and reliable method ofadvancing the life of tools under the action of turning, milling, drilling, punching

3、 andcutting. This pr outlines the ways in whiicro blasted tools, both coated anduncoated have benefited from shot blasting and resulted in greatroductivity, lowercutting forThe pro, improved surface finish of the work pieand less machine downtime.s of micro blasting is discussedhe pr. Its effectiven

4、ess depends onmany parameters including the shot media and size, the mechanics of impact and theapplication of the shot via the micro shot blasting unit.Control of the pros to provide repeatability and reliabilityhe shot blasting unitis discussed. Comparisons betn treated and untreated cutting tools

5、 are made andresults of tool life for these cutting tips outlined. The promajor benefitto tool life improvement. 2004 Elseviers has shown to be of.s.Keywords: Micro shot blasting; Surface finish; Machine tools1.roductionMany modern techniques have been developed to enhance the life of components ins

6、ervice, such as alloying additions, heat treatment, surface engineering, surfacecoating, implanion proses, laser treatment and surfahdesign. Prosessuch as thin film technology, plasma spraying, vacuum techniques deiting a rangeof multi-layered coatings have grey enhanced the life, use and applicatio

7、ns ofengineering components and machine tools. Bombardment with millions of microshot ranging in size from 4 to 50 lm wicontrolled pros can lead to dramaticoperating life improvements of components. Standard shot peening wasused in aproduction pros to extend the life of valve springs for Buick and C

8、adillac engineshe early 1930s 1,2 but prior to this it was a well known pros used byblacksmiths and sword makers overtime to improve the toughness of the cutting edgesof their tools and weapons. Today, cutting tips and tools can be grey improved bythe pros of micro shot blasting their surfato induce

9、 compressive residualstresses. The operating life of toolch as drills, turning tips,milling tips, punches,knife edges, slicers, blades, and a range of other working parts cso benefit fromthis pros.Standard components, such as springs, dies, shafts, cams, and dynamiccomponentsachines and engines can

10、be enhanced by this pros. The fatigue lifeof compressor components for exle, treated by shot peening have increaseddramatically as reported by Eckersley and Ferrelli 3. Other factorch as improvedfatiguefinish c, micro crack closure, reduced corroand an improved surfaceso be designedo components as a

11、 result of this the peening pros.Not only can improvements be made to the surface finish of the cutting tips and toolsbut also the surface finish of the work piemachined with these tools haveimproved as a result of this technique. Engineering materialch as tools steels,carbides, ceramics, coated car

12、bides, through to polymers and even rubbers(elastomers) can benefit. The key requirement for this pros is to developanautomated micro blasting pros to fit inside a spraybooth or standard shot blastingbooth. Shot material, size and mass, operating preres, operating velocities, kineticenergy, density

13、and coverage time will need to be perfected and optimised for a rangeof materials. The pros is a line of sight method ban be appd to complexsurfahch as the tips of drill bits.2. Method of operationOne of the primary wayst components fail in ervice is through fatigue. This isclosely assoted with cycl

14、ic stresses and accelerated by tensile stresses, micro crackpropagation and stress corrocracking. Cracks reduce the cross section of amaterial and eventually it will fail to support the appd loads. One simple method ofreducing failure by fatigue is to arrest these tensile stresses by inducing compre

15、ssivestresseso a surface. The benefits obtained with shot peening are a direct result ofthe residual compressive stresses produced in a component. A typical shot striking asurface is shown in Fig. 1. Any appd tensile loads would have toe theresidual compressive stresses before a crack could initiate

16、 as described by Almen 4.Poor machining of materials can result in residual stresses accruing at the surface.Rough surfahave deeper notches, where cracks can initiate due to tensile stressconcentrations at these pos. Many standard machining prosech as grinding,milling, turning, and coating prosech a

17、s electroplating induce residual tensilestresses in surfaand this can lead to early failure of components. Further tensileloading in service would lead to early failure and this can be prevented by shotpeening and micro blasting of component surfa. Micro shot blasting will changethe following in a m

18、aterialrface:(i)(ii)to fatigue fracture;to stress corro;a change in residual stresses;modification of surface finish.It is a cold working pros involving bombardingderch as ceramics, glassand metals of mainly spherical shs against surfaand can be used in conjunctionwith othroses. The main stages invo

19、lvedhis dynamic pros include elasticrecovery of the substrate after impact, some plastic deformation of the substrate if theimpact prere exceeds the yield stress, increased plastic deformation due to anincrease in impact prere and finally some rebound of the shot due to a release ofelastic energy. S

20、ome critical design characteristics of the micro shot peening prosinclude the shot size, sh, hardness, density, durability, angle of impact, velocityandensity. All of these parameters will influence the residual compressive stressesproducedhe substrate.3. Experimental workTool materialch as Tungsten

21、 Carbide, High Speed Steels usedilling andturning tools weresubjected to the micro peening pros using different shot media(ceramic and glass bead) and shot size. Tests prior to and following the blastingpros were conducted to ascertain any improvements resulting from the pros.The micro shot peening

22、unit is shown in Photo 1 it incorporates an air filter, prereregulator and gauge, air flow regulator, prerised blast media container and aventuri blast nozzle for directing the stream of micro shot. The unit is PLC controlledand a stepper motor, used to drive a lead screw, is used to move the blast

23、nozzleacross the sle in order to control media shot coverage.The blast nozzle cso be roed to allow shot media to strike the sles atdifferent angles. Tests undertaken include surface finish and roughness measurement,machining tests on standard lathes and mills, hardness tests, cutting foron turningop

24、erations, tool wear and the determination of surface finish of the work piemachined. Figs. 2 and 3 show a typical high speed steel (HSS) tip prior to andfollowing the micro shot peening pros using ceramic bead at a prere of 5.5 bar.4. Experimental resultsTesting of treated and untreated cutting tips

25、 and tools was conducted on HSSs forturning and milling as well as coated and uncoated carbide inserts. A dynamometerwas used to measure cutting foron the turning tool (Lathe). The cutting prosconsisted of a depth of cut of 2 mm on a standard bright mild steel specimen over alength of 750 mm while m

26、illing tests consisted of machining a 25_25_150 mm pieceof mild steel using a depth of cut of 1 mm wislot milling cutter of 18 mmdiameter. Surface roughness measurements were conducted on the machined components prior to and after machining to establish whether the treated cutting tips had superior

27、performance to the untreated tips. Micro Hardness testing was alsocarried out to establish if there was any increase in surface hardness due to the microshot peening pros. The impact angle of the shot was se90_ as this provides theoptimum compressive layer 5. The shot velocity on impact wisurface is

28、 largelydependent on the nozzle size, the air prere and the distance from the substrate. Theexure time was adequate to give sufficient coverage of the substrate and this wasdetermined by the Almen strip saturation time, work piece indenion time and visualappearance. Harder materialch as carbides wil

29、l obviously require longer exuretime or harder shot media. The micro peening media used was a ceramic bead ofapproximay 40 lm diametroviding high impact strengnd hardness (NF L06-824, approximay 60 HRc).Micro hardness testsCombined Vickers micro hardness tests gave the results and untreated HSS cutt

30、ing tips.Surface roughness valuesable 1. for both treatedIn all surface roughness tests conducted, the micro blasted surface gave animproved surface roughness value. Surface roughness and profile tests were carriedout on boTalyor Hobson Tallysurf instrument and a non contact surfaceprofileometer. Su

31、rface roughness details of a typicatreated HSS cutting tip and atreated one are shown in Figs. 4 and5 and Table 2 shows the results of surfacemeasurement values for other cutting tips and tools and workpie. Fig. 6 shows anuncoated carbide cutting tip which was not subjected to micro blasting. The fl

32、wear was measured using an optical microscope and the value recorded was 150 lm after 676 s of machining. Fig. 7 shows an uncoated carbide tip subjected to microblasting. The flwearhis case is only 90 lm for the same machining time.and5 and Table 2 shows the results of surface measurement values for

33、 other cuttingtips and tools and workpie. Fig. 6 shows an uncoated carbide cutting tip which wasnot subjected to micro blasting. The flwear was measured using an opticalmicroscope and the value recorded was 150 lm after 676 s of machining. Fig. 7 showsan uncoated carbide tip subjected to micro blast

34、ing. The fl90 lm for the same machining time.wearhis case is only4.3. Dynamometer testsFigs. 8 and 9 show the comparison for Dynamometer results for HSS (micro blasted) and untreated ses with relevant comments.he treatedSimilar profiles are shown for coated and uncoated turning tips in both the trea

35、ted(micro blasted) and untreated conditions in Figs. 1013. In all cases, the micro blastedtips provided an increase in cutting tip life with lower cutting forrecorded.5.sThis research work has shownt micro shot blasting of cutting tips and tools has averyitive effect on component surfaby increasing

36、toughness, operating life,improving hardness and surface finish. From the tests conducted, it is obvioust thepros affects the residual stresses at or near the surface in a benefil way byinducing compressive stresses on the substrates tested. The micro blasting provery simple to apply and economical

37、to use. The mechanical properties of thes issubstrates will determine the type of treatment, i.e. shordness, velocity andduration of application in order to obtaaximum benefits from this pros. Insome cases, authors have reported a 4 10 fold improvement in fatigue life in a rangeof dynamic machine pa

38、rtbjected to standard shot blasting. Further testing willneed to be conducted at the micro shot blasting stage to obtain similar benefits. Otherapplications for the micro blasting pros are currently being investigated and rubberbased productst are subjected to fatigue and wear are being tested in or

39、der toremove the surface voidst astress concentrationshese materials.ReferenImpact. Bloomfield, CT: Metal Improvement Company; Fall 1989.Zimmerli FP. Heat treating, setting and shot-peening of mechanicalsprings. Metal pros; June 1952.3 Eckersley JS, Ferrelli B. Using shot-peening to multiply the lif

40、e ofcompressor components. In: The shot peener,ernational newsletterfor shot-peening surface finishing industry, vol. 9, I1; March 1995.e No.4 Almen JC. J.O. Almen on hot blasting. General motors test, USPatent 2,350,440.5 Chaigne J. Controlled shot peening. Elec Inc., Report; 1989.制造业用于提高表面光洁度和减少切削

41、力的抛丸机摘要在旋转，铣削，钻孔，冲孔和切削运动中，微抛丸切削技巧和工具是一种提高工具的非常高效并且可靠的方法。本文概述了应用微抛丸工具的方式，微抛丸对有无镀膜工件的益处，并且创造了更大的生产力，降低了切应力，提高了工件的表面光洁度，减少了机器的停机时间。本文对微抛丸过程进行了。它的效率取决于包括弹丸和型号在内的许多参数，碰撞力学和通过微抛丸单元的弹丸的应用程序。对控制流程提供的可重复性和可靠性的装置进行了探讨。处理和处理的刀具的做出了对比，切割技巧对刀具的影响做出了概述。这个过程体现了提高工具的主要好处。2004 爱思保留所利。:微喷丸,表面光洁度;机床介绍许多现代技术已经开发出来加强服务组

42、件的，例如添加合金，热处理，表面工程，表面涂层，移植过程，激光治疗以及表面外形设计。例如薄膜技术，等离子喷涂，沉淀多层涂料的真空技术都大大加强了，工程和应用程序组件和机床使用。通过控制过程用数以百万计的大小在 4 到 50 微米的微抛丸撞击可以显著提高组件的使用。标准喷丸技术首次使用时在 20 世纪 30 年代提高别克和凯迪拉克引擎气门弹簧的生产过程中，但在此之前该技术就是被铁匠和刀制造商所熟知的来提高他们工具和切削刃韧性的过程。，切割技巧和工具可以通过微抛丸它们的表面的过程来引导压缩参与应力而被大大提高。钻头，车削头，铣削头，冲头，刀刃，切片机，叶片以及一系列的其他工作部分都可以受益于该过程

43、。机器和引擎中的标准组件，例如离合器，柴油机，轴，凸轮以及动态组件等都可以通过该过程提高。由Eckersley和Ferrelli所述，例如压缩机组件的疲劳通过抛丸处理可以显著增加。其他，例如抗疲劳强度，微裂纹闭合，减少腐蚀以及提高表面光洁度都可以被作为喷丸的结果而被设计进组件当中。不仅可以做到切削刀具表面光洁度的提高，而且由这些刀具加工的工件的表面光洁度作为该技术的一个成果也得到了提高。工程材料中，例如工具钢，硬质合金，陶瓷，涂层硬质合金，通过聚合物甚至橡胶（弹性物）都可以受益。这个过程的关键要求是开发一个自动化微抛丸的工艺过程来适用于喷漆柜或者标准抛丸位置。抛丸材料，大小和质量，操作压力，操

44、作速度，动能，密度，覆盖时间都要被完美优化一系列材料。这个过程是一种视线方法却可以应用于复杂外形例如钻孔。操作方法服务组件损坏的主要原因之一是疲劳使用。这是与循环应力密切相关,加速了抗拉应力，微裂纹扩展和应力腐蚀开裂。裂纹减少材料的横截面，最终它将无法支持应用加载。减少疲劳的一个简单方法是通过诱导压应力到表面来停止这些拉伸应力。抛丸加工直接产生的好处是一个组件产生的残余压应力。典型的镜头的表面是图1所示。在由阿尔门4描述的裂纹出现之前，任何应用拉伸加载将不得不克服残余压应力。不良的加工材料会导致残留表面压力积累。粗糙表面有更次的等级，在这些点，由于拉应力会产生裂纹。许多标准磨削，铣削、车削和涂层工艺例如电镀等加工过程，在表面产生残应力，这可能会导致早期失效的组件。进一步拉伸加载服务会导致早期失效，这可以防止喷丸加工和微抛丸组件表面。微抛丸处理将改变以下材料表面：1. 抗疲劳断裂；2. 抗应力腐蚀；3. 残余应力的变化；