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1、<p>  The New Concept Of Cutting Processing</p><p>  The nowadays cutting tool company cannot only be again the manufacture and the sales cutting tool, in order to succeed, they must be consistent with

2、the globalization manufacture tendency maintenance, through enhances the efficiency, cooperates with the customer reduces the cost. Approaches the instantaneous global competition after this after NAFTA, the WTO time, th

3、e world company is making quickly to the same feeling, is lighter, a cheaper response. In other words, they make the product and th</p><p>  For example, takes the modular cast iron to say that, it has becom

4、e the engine part and other automobiles, the agriculture the material which see day by day with the equipment and in the machine tool industry components. This kind of alloy provides the low production cost and the good

5、machine capability combination. They are cheaper than the steel products, but has a higher intensity and toughness compared to the cast iron. But at the same time the modular cast iron is extremely wear-resisting, </p

6、><p>  May estimate that, the high degree of hardness and the high wear-resisting cutting material quality must consider the modular cast iron the high resistance to wear. And the material quality contains extr

7、emely hard TiC in fact (carbonized titanium) or TiCN (carbon titanium nitrides) thick coating when cutting speed each minute 300 meters processes the modular cast iron to prove usually is effective. But along with cuttin

8、g speed increase, scrap/The cutting tool junction plane temperature also is i</p><p>  The chemical stability becomes an important performance performance dividing line compared to the resistance to wear the

9、 factor, the speed and the temperature is decided in is processed the modular cast iron the crystal grain structure and the performance. But usually thick coating of TiCN and TiC or only ductile iron oxides in the soil c

10、oating is applied to, because the today majority of this kinds are processed the material the cutting speed in each minute 150 to 335 meters between. Is higher </p><p>  In order to cause this scope performa

11、nce to be most superior, the mountain high researched and developed and has promoted in view of modular cast iron processing material quality TX150. This kind of material quality has hard also the anti- distortion subst

12、rate, is very ideal regarding the processing modular cast iron. Its coating the oxide compound coating which hollowly wears by thick very wear-resisting carbon titanium nitrides and a thin anti- crescent moon, the top is

13、 thin layer TiN. This k</p><p>  The coating ceramics also display can effectively process the modular cast iron. In the past, the aluminum oxide ceramics application which not the coating tough good such as

14、 nitriding silicon and the silicon carbide textile fiber strengthened the work piece material chemistry paralysis limit. Today but could resist the scrap distortion process through the use to have the high thermal coatin

15、g cutting tool life already remarkably to increase. But certain early this domains work piece processing u</p><p>  When machining, the work piece has processed the surface is depends upon the cutting tool a

16、nd the work piece makes the relative motion to obtain.According to the surface method of formation, the machining may divide into the knife point path law, the formed cutting tool law, the generating process three kinds.

17、</p><p>  The knife point path law is depends upon the knife point to be opposite in the work piece surface path, obtains the superficial geometry shape which the work piece requests, like the turning outer

18、annulus, the shaping plane, the grinding outer annulus, with the profile turning forming surface and so on, the knife point path are decided the cutting tool and the work piece relative motion which provides in the engin

19、e bed; </p><p>  The formed cutting tool law abbreviation forming, is with the formed cutting tool which matches with the work piece final superficial outline, or the formed grinding wheel and so on processe

20、s the formed surface, like formed turning, formed milling and form grinding and so on, because forms the cutting tool the manufacture quite to be difficult, therefore only uses in processing the short formed surface gene

21、rally; </p><p>  The generating process name rolls cuts method, is when the processing the cutting tool and the work piece do unfold the movement relatively, the cutting tool and the work piece centrode make

22、 the pure trundle mutually, between both maintains the definite transmission ratio relations, obtains the processing surface is the knife edge in this kind of movement envelope, in the gear processing rolls the tooth, th

23、e gear shaping, the shaving, the top horizontal jade piece tooth and rubs the tooth and so</p><p>  The machining quality mainly is refers to the work piece the processing precision and the surface quality (

24、including surface roughness, residual stress and superficial hardening).Along with the technical progress, the machining quality enhances unceasingly.The 18th century later periods, the machining precision counts by the

25、millimeter; At the beginning of 20th century, machining precision Gao Yida 0.01 millimeter; To the 50's, the machining precision has reached a micron level; The 70's, the ma</p><p>  The influence ma

26、chining quality primary factor has aspects and so on engine bed, cutting tool, jig, work piece semifinished materials, technique and processing environment.Must improve the machining quality, must take the suitable measu

27、re to the above various aspects, like reduces the engine bed work error, selects the cutting tool correctly, improves the semifinished materials quality, the reasonable arrangement craft, the improvement environmental co

28、ndition and so on. </p><p>  Enhances the cutting specifications to enhance the material excision rate, is enhances the machining efficiency the essential way.The commonly used highly effective machining met

29、hod has the high-speed cutting, the force cutting, the plasma arc heating cuts and vibrates the cutting and so on. </p><p>  The grinding speed is called the high-speed grinding in 45 meters/second above cut

30、tings.Uses the high-speed cutting (or grinding) both may enhance the efficiency, and may reduce the surface roughness.The high-speed cutting (or grinding) requests the engine bed to have the high speed, the high rigidity

31、, the high efficiency and the vibration-proof good craft system; Requests the cutting tool to have the reasonable geometry parameter and the convenience tight way, but also must consider the safe re</p><p> 

32、 The force cutting refers to the roughing feed or cuts the deep machining greatly, uses in the turning and the grinding generally.The force turning main characteristic is the lathe tool besides the main cutting edge, but

33、 also some is parallel in the work piece has processed superficial the vice-cutting edge simultaneously to participate in the cutting, therefore may enhance to feed quantity compared to the general turning several times

34、of even several times.Compares with the high-speed cutting, t</p><p>  The vibration cutting is along the cutting tool direction of feed, the attachment low frequency or the high frequency vibration machinin

35、g, may enhance the cutting efficiency.The low frequency vibration cutting has the very good chip breaking effect, but does not use the chip breaking equipment, makes the knife edge intensity to increase, time the cutting

36、 total power dissipation compared to has the chip breaking installment ordinary cutting to reduce about 40%.The high frequency vibration cutting</p><p>  To lumber, plastic, rubber, glass, marble, granite an

37、d so on nonmetallic material machining, although is similar with the metal material cutting, but uses the cutting tool, the equipment and the cutting specifications and so on has the characteristic respectively. </p&

38、gt;<p>  The lumber product machining mainly carries in each kind of joiner's bench, its method mainly has: The saw cuts, digs cuts, the turning, the milling, drills truncates with the polishing and so on. <

39、;/p><p>  The plastic rigidity is worse than the metal, the easy bending strain, the thermoplastic thermal conductivity to be in particular bad, easy to elevate temperature the conditioning.When cutting plastic

40、, suitably with the high-speed steel or the hard alloy tools, selects the small to feed quantity and the high cutting speed, and uses compressed air cooling.If the cutting tool is sharp, the angle is appropriate, may pro

41、duce the belt-shaped scrap, easy to carry off the quantity of heat. </p><p>  Glass (including semiconducting material and so on germanium, silicon) but degree of hardness high brittleness is big.To methods

42、and so on glass machining commonly used cutting, drill hole, attrition and polishing.To thickness in three millimeters following glass plates, the simple cutting method is with the diamond or other hard materials, in gla

43、ss surface manual scoring, the use scratch place stress concentration, then uses the hand to break off.</p><p>  To the marble, the granite and the concrete and so on the hard material processing, mainly use

44、s methods and so on cutting, turning, drill hole, shaping, attrition and polishing.When cutting the available circular saw blade adds the grinding compound and the water; The outer annulus and the end surface may use the

45、 negative rake the hard alloy lathe tool, by 10~30 meter/minute cutting speed turning; Drills a hole the available hard alloy drill bit; The big stone material plane available hard alloy</p><p>  Cutting too

46、l in hot strong alloy application</p><p>  The aviation processing also changes rapidly. For example, nickel base heat-resisting alloy like several years ago the most people had not heard Rene88 now occupies

47、 to the aircraft engine manufacture uses the total metal quantity 10~25%. Has very good showing and the commercial reason regarding this. For example, these heat strong alloy will be able to increase the engine endurance

48、 moreover to permit the small engine work on the big airplane, that will enhance the combustion efficiency and reduc</p><p>  As a result of changes in these conditions, can be very pleased to have processed

49、 many titanium alloys and nickel-based alloy materials C-2 hard metal alloys, in the application to today's cutting edge of blade to the crushing and cutting depth of the trench lines badly worn. But using the latest

50、 high-temperature processing of small particles hard metal alloys to be effective, cutlery life improved, but more importantly to enhance the reliability of applications in high-temperature alloys. Small</p><p

51、>  PVD (physical gas phase deposition) coating also by certificate effective processing heat-resisting alloy. TiN (titanium nitrides) the PVD coating was uses and still was most early most receives welcome. Recently,

52、TiAlN (nitrogen calorization titanium) and TiCN (carbon titanium nitrides) the coating also could very good use. In the past the TiAlN coating application scope and TiN compared the limit to be more. But after the cuttin

53、g speed enhances them is a very good choice, enhances the producti</p><p>  Recently, used in the heat-resisting alloy application material quality already developing, these coating but became by several com

54、binations. The massive laboratories and the scene test has already proven this kind of combination and other any kind of sole coating compares in time the very wide scope application is very effective. Therefore aims at

55、the heat-resisting alloy application the PVD compound coating possibly to become the focal point which the hard alloy new material quality research a</p><p>  Dry processing</p><p>  Including t

56、he refrigerant question is technical and the commercial expansion industrial production tendency another domain which the cutting tool makes. North America and the European strict refrigerant management request and the b

57、iggest three automobile manufacturer forces them the core supplier to obtain the ISO14000 authentication (the ISO9000 environment management edition), this causes the refrigerant processing cost rise. To the car company

58、and their core supplier said obviously one of res</p><p>  Recently, already appeared some to concern this topic to promulgate the speed, to enter for, the coating chemical composition and other parameters v

59、ery substantial comprehensive nature very strong useful technical papers. Wants to concentrate the elaboration in here me "does the processing viewpoint" in the operation and commercial meaning automobile manuf

60、acturer new.</p><p>  The metal working jobholders can the very good understanding related refrigerant use question, but majority cannot understand concerns except the technical challenge (for example row of

61、 filings) beside does the processing question in the cutting tool - work piece contact face between. Usually may observe to the refrigerant disperser scrap which flows out, but the pressure surpasses 3,000 pounds/An inch

62、 2 high speed refrigerant also can help to break the filings, specially soft also the continual</p><p>  Uses does the cutting craft the components result is the engine bed uses the wet type processing compo

63、nents to be hotter than. Whether before you do allow them to survey in the open-air natural cooling? If processes newly the hot components put frequently to the turnover box, elevates the environment temperature, whethe

64、r components full cooling and just right enough permission precision examination? Also has the handling side several dozens on hundred components to be able to operate the worker</p><p>  With many cutting t

65、ools/The work piece technical question same place, these latent questions need to state whether dryly adds the ability line. Luckily, has very many ways to elaborate these questions. For example, the compressed air was p

66、roven row of filings becomes the question in very many applications the situation to have the successful echo.</p><p>  Another plan is called MQL (minimum lubrication) a technology, it replaces the traditio

67、nal refrigerant by the application the quite few oil mists constitution. This is a recognition compromise plan, this kind of minimum technology can large scale reduce the refrigerant the headache matter, moreover the smo

68、oth finish which processes in many applications very is also good. This domain still had very many research to do, moreover the cutting tool company positively participated in such research was</p><p>  In t

69、he factory the special details design other perhaps better plan according to the world in. The manufacturing industry jobholders possibly still could ask why they do have to use recent development the technology to repla

70、ce the refrigerant method diligently which the tradition already an experience number generation of person improved enhances, because implemented especially does the experiment and the defeat which the processing or the

71、subarid processing produced possibly causes the higher s</p><p>  Perhaps does the dry processing is not all suits to each application, but above discusses likely other processing questions are same, needs f

72、rom a wider operation, the environment and the commercial angle appraises. Will be able to help the cutting tool company which the customer will do this to have the competitive advantage, but these will not be able to pr

73、ovide unceasingly is in the passive position.</p><p>  Cutting tool and nanotechnology</p><p>  Can fiercely change the cutting tool industry the enchanting new domain is the miniature manufactu

74、re, or the processing small granule forms the product which needs. Must refer to is its here does not have about the cutting tool miniature manufacture first matter; Second must say the matter is it is not remote. </p

75、><p>  Why the miniature manufacture and are the cutting tool related. Because most main is the particle size smaller, the hard alloy toughness of material better also is more wear-resisting. (Some experts defi

76、ne with the nanometer level pellet for are smaller than 0.2 mu m, but other people persisted a nanometer pellet had to be smaller than the hard alloy tools prototype which 0.1 mu m) made already to complete and the test,

77、It is said that wear resistant theatrically increase. The question is the nan</p><p><b>  切削加工新概念</b></p><p>  現(xiàn)今的刀具公司再也不能只是制造和銷售刀具,為了成功,他們必須與全球化制造趨勢(shì)保持一致,通過(guò)提高效率、同客戶合作來(lái)降低成本。在這個(gè)近乎瞬間的全球

78、競(jìng)爭(zhēng)的后NAFTA、后WTO時(shí)代,全世界的公司正對(duì)相同感覺(jué)作出更快、更輕、更便宜的反應(yīng)。換句話說(shuō),他們制造的產(chǎn)品和零件包含能在高速下運(yùn)轉(zhuǎn),由于成本的壓力,最好、更輕而且要制造更便宜。取得這些目標(biāo)的一個(gè)最佳途徑是通過(guò)發(fā)展和應(yīng)用新材料,但這些新的和改進(jìn)的材料通常都難以加工。這種商業(yè)上的動(dòng)力和技術(shù)上的困難的組合在汽車和航空工業(yè)尤其突出,并已成為有見(jiàn)識(shí)的刀具公司研發(fā)部門的首要驅(qū)動(dòng)力。 </p><p>  例如,拿球墨鑄

79、鐵來(lái)說(shuō),它已成為發(fā)動(dòng)機(jī)零件和其它汽車、農(nóng)用設(shè)備和機(jī)床工業(yè)上的零件的日益見(jiàn)的材料。這種合金提供較低的生產(chǎn)成本和良好的機(jī)械性能的組合。他們比鋼材便宜,而比鑄鐵有更高的強(qiáng)度和韌性。但同時(shí)球墨鑄鐵非常耐磨,有快速磨壞刀具材料的傾向。這種耐磨性很大程度上受珠光體含量影響。某一已知球墨鑄鐵的珠光體含量越高,它的耐磨性越好,而且它的可加工性越差。另外,球墨鑄鐵的多孔性導(dǎo)致斷續(xù)切削,這更加降低壽命。 </p><p>  可以預(yù)

80、計(jì),高硬度和高耐磨的切削材質(zhì)需考慮球墨鑄鐵的高耐磨性。并且事實(shí)上材質(zhì)包含極硬的TiC(碳化鈦)或TiCN(碳氮化鈦)的厚涂層在切削速度每分鐘300米時(shí)加工球墨鑄鐵被證明通常是有效的。但是隨著切削速度的增加,切屑/刀具結(jié)合面的溫度也在增加。當(dāng)發(fā)生這樣的情況,TiC涂層傾向于和鐵發(fā)生化學(xué)反應(yīng)并軟化,更多的壓力作用在抗月牙洼磨損的涂層上。在這些條件下,希望有一種化學(xué)穩(wěn)定性更好的涂層,如Al2O3(雖然在較低的速度下不如TiC硬或耐磨)。

81、 化學(xué)穩(wěn)定性比耐磨性更成為一個(gè)重要的表現(xiàn)性能分界的因素,速度和溫度取決于被加工球墨鑄鐵的晶粒結(jié)構(gòu)和性能。但是通常厚涂層的TiC或TiCN和僅有氧化物的較薄涂層是針對(duì)球墨鑄鐵應(yīng)用的,因?yàn)榻裉齑蟛糠诌@類被加工材料的切削速度在每分鐘150到335米之間。對(duì)于速度高于每分鐘300米的應(yīng)用,人們對(duì)這種材料是滿意的。 為了使這個(gè)范圍性能最優(yōu),山高研發(fā)和推出了針對(duì)球墨鑄鐵加工的材質(zhì)TX150。這種材質(zhì)有一個(gè)硬且抗變形的基體,對(duì)于加工球墨鑄鐵

82、很理想。它的涂層由一層較厚的很耐磨的碳氮化鈦和一層較薄的抗月牙洼磨損的氧化物涂層,頂面是一薄層TiN。這種涂層運(yùn)用</p><p>  切削加工時(shí),工件的已加工表面是依靠切削工具和工件作相對(duì)運(yùn)動(dòng)來(lái)獲得的。按表面形成方法,切削加工可分為刀尖軌跡法、成形刀具法、展成法三類。</p><p>  刀尖軌跡法是依靠刀尖相對(duì)于工件表面的運(yùn)動(dòng)軌跡,來(lái)獲得工件所要求的表面幾何形狀,如車削外圓、刨削平面、

83、磨削外圓、用靠模車削成形面等,刀尖的運(yùn)動(dòng)軌跡取決于機(jī)床所提供的切削工具與工件的相對(duì)運(yùn)動(dòng);</p><p>  成形刀具法簡(jiǎn)稱成形法,是用與工件的最終表面輪廓相匹配的成形刀具,或成形砂輪等加工出成形面,如成形車削、成形銑削和成形磨削等,由于成形刀具的制造比較困難,因此一般只用于加工短的成形面;</p><p>  展成法又稱滾切法,是加工時(shí)切削工具與工件作相對(duì)展成運(yùn)動(dòng),刀具和工件的瞬心線相互

84、作純滾動(dòng),兩者之間保持確定的速比關(guān)系,所獲得加工表面就是刀刃在這種運(yùn)動(dòng)中的包絡(luò)面,齒輪加工中的滾齒、插齒、剃齒、珩齒和磨齒等均屬展成法加工。有些切削加工兼有刀尖軌跡法和成形刀具法的特點(diǎn),如螺紋車削。</p><p>  切削加工質(zhì)量主要是指工件的加工精度和表面質(zhì)量(包括表面粗糙度、殘余應(yīng)力和表面硬化)。隨著技術(shù)的進(jìn)步,切削加工的質(zhì)量不斷提高。18世紀(jì)后期,切削加工精度以毫米計(jì);20世紀(jì)初,切削加工的精度最高已達(dá)0

85、.01毫米;至50年代,切削加工精度已達(dá)微米級(jí);70年代,切削加工精度又提高到0.1微米。</p><p>  影響切削加工質(zhì)量的主要因素有機(jī)床、刀具、夾具、工件毛坯、工藝方法和加工環(huán)境等方面。要提高切削加工質(zhì)量,必須對(duì)上述各方面采取適當(dāng)措施,如減小機(jī)床工作誤差、正確選用切削工具、提高毛坯質(zhì)量、合理安排工藝、改善環(huán)境條件等。</p><p>  提高切削用量以提高材料切除率,是提高切削加工

86、效率的基本途徑。常用的高效切削加工方法有高速切削、強(qiáng)力切削、等離子弧加熱切削和振動(dòng)切削等。</p><p>  磨削速度在45米/秒以上的切削稱為高速磨削。采用高速切削(或磨削)既可提高效率,又可減小表面粗糙度。高速切削(或磨削)要求機(jī)床具有高轉(zhuǎn)速、高剛度、大功率和抗振性好的工藝系統(tǒng);要求刀具有合理的幾何參數(shù)和方便的緊固方式,還需考慮安全可靠的斷屑方法。</p><p>  強(qiáng)力切削指大進(jìn)

87、給或大切深的切削加工,一般用于車削和磨削。強(qiáng)力車削的主要特點(diǎn)是車刀除主切削刃外,還有一個(gè)平行于工件已加工表面的副切削刃同時(shí)參與切削,故可把進(jìn)給量比一般車削提高幾倍甚至十幾倍。與高速切削比較,強(qiáng)力切削的切削溫度較低,刀具壽命較長(zhǎng),切削效率較高;缺點(diǎn)是加工表面較粗糙。強(qiáng)力切削時(shí),徑向切削力很大故不適于加工細(xì)長(zhǎng)工件。</p><p>  振動(dòng)切削是沿刀具進(jìn)給方向,附加低頻或高頻振動(dòng)的切削加工,可以提高切削效率。低頻振動(dòng)

88、切削具有很好的斷屑效果,可不用斷屑裝置,使刀刃強(qiáng)度增加,切削時(shí)的總功率消耗比帶有斷屑裝置的普通切削降低40%左右。高頻振動(dòng)切削也稱超聲波振動(dòng)切削,有助于減小刀具與工件之間的摩擦,降低切削溫度,減小刀具的粘著磨損,從而提高切削效率和加工表面質(zhì)量,刀具壽命約可提高40%。</p><p>  對(duì)木材、塑料、橡膠、玻璃、大理石、花崗石等非金屬材料的切削加工,雖與金屬材料的切削類似,但所用刀具、設(shè)備和切削用量等各有特點(diǎn)。

89、</p><p>  木材制品的切削加工主要在各種木工機(jī)床上進(jìn)行,其方法主要有:鋸切、刨切、車削、銑削、鉆削和砂光等。</p><p>  塑料的剛度比金屬差,易彎曲變形,尤其是熱塑性塑料導(dǎo)熱性差,易升溫軟化。故切削塑料時(shí),宜用高速鋼或硬質(zhì)合金刀具,選用小的進(jìn)給量和高的切削速度,并用壓縮空氣冷卻。若刀具鋒利,角度合適,可產(chǎn)生帶狀切屑,易于帶走熱量。</p><p>

90、  玻璃(包括鍺、硅等半導(dǎo)體材料)的硬度高而脆性大。對(duì)玻璃的切削加工常用切割、鉆孔、研磨和拋光等方法。對(duì)厚度在三毫米以下的玻璃板,最簡(jiǎn)單的切割方法是用金剛石或其他堅(jiān)硬物質(zhì),在玻璃表面手工刻劃,利用刻痕處的應(yīng)力集中,即可用手折斷。</p><p>  對(duì)大理石、花崗石和混凝土等堅(jiān)硬材料的加工,主要用切割、車削、鉆孔、刨削、研磨和拋光等方法。切割時(shí)可用圓鋸片加磨料和水;外圓和端面可采用負(fù)前角的硬質(zhì)合金車刀,以10~3

91、0米/分的切削速度車削;鉆孔可用硬質(zhì)合金鉆頭;大的石料平面可用硬質(zhì)合金刨刀或滾切刨刀刨削;精密平滑的表面,可用三塊互為基準(zhǔn)對(duì)研的方法,或磨削和拋光的方法獲得。</p><p>  刀具在熱強(qiáng)合金中的應(yīng)用 </p><p>  航空加工也變化迅速。例如,鎳基高溫合金如幾年前多數(shù)人未聽(tīng)說(shuō)過(guò)的Rene88現(xiàn)在占到航空發(fā)動(dòng)機(jī)制造使用總金屬量的10~25%。對(duì)于這個(gè)有很好的表現(xiàn)和商業(yè)理由。例如,這些

92、熱強(qiáng)合金能增加發(fā)動(dòng)機(jī)壽命而且允許較小的發(fā)動(dòng)機(jī)工作在大飛機(jī)上,那將提高燃燒效率并降低運(yùn)營(yíng)成本。這些韌性好的材料也把費(fèi)用呈現(xiàn)在刀具上。它們的耐熱性導(dǎo)致刀尖上的溫度更高,從而降低了刀具壽命。相似地,這些合金里的碳化物顆粒顯著增加了摩擦,從而縮短刀具壽命。 作為這些條件改變的結(jié)果,曾經(jīng)能很滿意地加工很多鈦合金和鎳基合金的硬質(zhì)合金材質(zhì)C-2在應(yīng)用到當(dāng)今的合金時(shí)遭受切削刃的壓碎和切削深度線處嚴(yán)重的溝槽磨損。但是用最新的細(xì)顆粒硬質(zhì)合金能有效

93、加工高溫合金,刀具壽命得到提高,更重要的是提高在高溫合金應(yīng)用時(shí)的可靠性。細(xì)顆粒硬質(zhì)合金有比傳統(tǒng)硬質(zhì)合金材質(zhì)更高的壓縮強(qiáng)度和硬度,只是在韌性方面增加少量的成本。而結(jié)果是在高溫合金加工上比傳統(tǒng)硬質(zhì)合金抵抗常見(jiàn)失效模式更有效。 PVD(物理氣相沉積)涂層也被證明有效加工高溫合金。TiN(氮化鈦)PVD涂層是最早使用的并仍然是最受歡迎的。最近,TiAlN(氮鋁化鈦)和TiCN(碳氮化鈦)</p><p>  

94、干切削,包括冷卻液在內(nèi)的問(wèn)題是刀具制造的科技和商業(yè)擴(kuò)大產(chǎn)業(yè)化趨勢(shì)的另一個(gè)領(lǐng)域。北美和歐洲嚴(yán)格冷卻液管理的要求和最大的三家汽車制造商強(qiáng)制它們的核心供應(yīng)商取得ISO14000認(rèn)證(ISO9000的環(huán)境管理版本),這使得冷卻液處理成本上升。對(duì)汽車公司和他們核心供應(yīng)商來(lái)說(shuō)明顯受歡迎的反應(yīng)之一是在特定的加工應(yīng)用里完全免除冷卻液的使用。這種干加工的新世界給刀具供應(yīng)商提出了一系列挑戰(zhàn)。 </p><p>  最近,已經(jīng)出現(xiàn)了一

95、些有關(guān)這個(gè)專題揭示速度、進(jìn)給、涂層化學(xué)成分和其它參數(shù)的很充實(shí)的綜合性很強(qiáng)的有用的技術(shù)文章。在這里我想集中論述在操作和商業(yè)含義上的汽車制造商的新“干加工觀點(diǎn)”。 </p><p>  金屬加工從業(yè)人員能很好理解有關(guān)冷卻液使用的問(wèn)題,但大多數(shù)不能理解有關(guān)除在刀具-工件接觸面間技術(shù)挑戰(zhàn)(例如排屑)之外的干加工問(wèn)題。通常可以觀察到流出的冷卻液分散切屑,但壓力超過(guò)3000磅/英寸2的高速冷卻液也能幫助斷屑,特別是軟且連續(xù)的

96、切屑會(huì)引起刀具-工件接觸面上的麻煩。 采用干切削工藝的零件的結(jié)果是機(jī)床比采用濕式加工零件的更熱。你是否允許它們測(cè)量前在露天自然冷卻?如果新加工的熱零件經(jīng)常放到周轉(zhuǎn)箱,升高周圍環(huán)境溫度,是否零件充分冷卻并正好足夠允許精度檢測(cè)?還有處置身邊幾十上百的零件會(huì)對(duì)操作工人增加額外負(fù)擔(dān)。 同許多刀具/工件的技術(shù)問(wèn)題一起,這些潛在的問(wèn)題需要陳述是否干加工能行。幸運(yùn)地,有很多途徑闡述這些問(wèn)題。例如,壓縮空氣被證明在很多應(yīng)用里排屑成為

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