拋丸機(jī)斗式提升機(jī)的設(shè)計(jì)翻譯

1、畢業(yè)設(shè)計(jì)（）英文資料翻譯Micro Shot Blasting of Machine Tools學(xué)院：西北工業(yè)大學(xué)明德學(xué)院專業(yè)：機(jī)械設(shè)計(jì)制造及自動(dòng)化班級(jí)：161003 班姓名：王 志 偉學(xué)號(hào)：103359指導(dǎo)老師：張 永 紅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.制造業(yè)用于提高表面光潔度和減少切削

41、力的拋丸機(jī)摘要在旋轉(zhuǎn)，銑削，鉆孔，沖孔和切削運(yùn)動(dòng)中，微拋丸切削技巧和工具是一種提高工具的非常高效并且可靠的方法。本文概述了應(yīng)用微拋丸工具的方式，微拋丸對(duì)有無(wú)鍍膜工件的益處，并且創(chuàng)造了更大的生產(chǎn)力，降低了切應(yīng)力，提高了工件的表面光潔度，減少了機(jī)器的停機(jī)時(shí)間。本文對(duì)微拋丸過(guò)程進(jìn)行了。它的效率取決于包括彈丸和型號(hào)在內(nèi)的許多參數(shù)，碰撞力學(xué)和通過(guò)微拋丸單元的彈丸的應(yīng)用程序。對(duì)控制流程提供的可重復(fù)性和可靠性的裝置進(jìn)行了探討。處理和處理的刀具的做出了對(duì)比，切割技巧對(duì)刀具的影響做出了概述。這個(gè)過(guò)程體現(xiàn)了提高工具的主要好處。2004 愛思保留所利。:微噴丸,表面光潔度;機(jī)床介紹許多現(xiàn)代技術(shù)已經(jīng)開發(fā)出來(lái)加強(qiáng)服務(wù)組

42、件的，例如添加合金，熱處理，表面工程，表面涂層，移植過(guò)程，激光治療以及表面外形設(shè)計(jì)。例如薄膜技術(shù)，等離子噴涂，沉淀多層涂料的真空技術(shù)都大大加強(qiáng)了，工程和應(yīng)用程序組件和機(jī)床使用。通過(guò)控制過(guò)程用數(shù)以百萬(wàn)計(jì)的大小在 4 到 50 微米的微拋丸撞擊可以顯著提高組件的使用。標(biāo)準(zhǔn)噴丸技術(shù)首次使用時(shí)在 20 世紀(jì) 30 年代提高別克和凱迪拉克引擎氣門彈簧的生產(chǎn)過(guò)程中，但在此之前該技術(shù)就是被鐵匠和刀制造商所熟知的來(lái)提高他們工具和切削刃韌性的過(guò)程。，切割技巧和工具可以通過(guò)微拋丸它們的表面的過(guò)程來(lái)引導(dǎo)壓縮參與應(yīng)力而被大大提高。鉆頭，車削頭，銑削頭，沖頭，刀刃，切片機(jī)，葉片以及一系列的其他工作部分都可以受益于該過(guò)程

43、。機(jī)器和引擎中的標(biāo)準(zhǔn)組件，例如離合器，柴油機(jī)，軸，凸輪以及動(dòng)態(tài)組件等都可以通過(guò)該過(guò)程提高。由Eckersley和Ferrelli所述，例如壓縮機(jī)組件的疲勞通過(guò)拋丸處理可以顯著增加。其他，例如抗疲勞強(qiáng)度，微裂紋閉合，減少腐蝕以及提高表面光潔度都可以被作為噴丸的結(jié)果而被設(shè)計(jì)進(jìn)組件當(dāng)中。不僅可以做到切削刀具表面光潔度的提高，而且由這些刀具加工的工件的表面光潔度作為該技術(shù)的一個(gè)成果也得到了提高。工程材料中，例如工具鋼，硬質(zhì)合金，陶瓷，涂層硬質(zhì)合金，通過(guò)聚合物甚至橡膠（彈性物）都可以受益。這個(gè)過(guò)程的關(guān)鍵要求是開發(fā)一個(gè)自動(dòng)化微拋丸的工藝過(guò)程來(lái)適用于噴漆柜或者標(biāo)準(zhǔn)拋丸位置。拋丸材料，大小和質(zhì)量，操作壓力，操

44、作速度，動(dòng)能，密度，覆蓋時(shí)間都要被完美優(yōu)化一系列材料。這個(gè)過(guò)程是一種視線方法卻可以應(yīng)用于復(fù)雜外形例如鉆孔。操作方法服務(wù)組件損壞的主要原因之一是疲勞使用。這是與循環(huán)應(yīng)力密切相關(guān),加速了抗拉應(yīng)力，微裂紋擴(kuò)展和應(yīng)力腐蝕開裂。裂紋減少材料的橫截面，最終它將無(wú)法支持應(yīng)用加載。減少疲勞的一個(gè)簡(jiǎn)單方法是通過(guò)誘導(dǎo)壓應(yīng)力到表面來(lái)停止這些拉伸應(yīng)力。拋丸加工直接產(chǎn)生的好處是一個(gè)組件產(chǎn)生的殘余壓應(yīng)力。典型的鏡頭的表面是圖1所示。在由阿爾門4描述的裂紋出現(xiàn)之前，任何應(yīng)用拉伸加載將不得不克服殘余壓應(yīng)力。不良的加工材料會(huì)導(dǎo)致殘留表面壓力積累。粗糙表面有更次的等級(jí)，在這些點(diǎn)，由于拉應(yīng)力會(huì)產(chǎn)生裂紋。許多標(biāo)準(zhǔn)磨削，銑削、車削和涂層工藝?yán)珉婂兊燃庸み^(guò)程，在表面產(chǎn)生殘應(yīng)力，這可能會(huì)導(dǎo)致早期失效的組件。進(jìn)一步拉伸加載服務(wù)會(huì)導(dǎo)致早期失效，這可以防止噴丸加工和微拋丸組件表面。微拋丸處理將改變以下材料表面：1. 抗疲勞斷裂；2. 抗應(yīng)力腐蝕；3. 殘余應(yīng)力的變化；