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1、<p><b>  附錄A</b></p><p><b>  外文翻譯</b></p><p><b>  原文:</b></p><p>  Putting Ceramic Tool to Rational Use </p><p>  ----W. C. Ye,

2、 F. Zhou, Huaiyin Institute of Industrial Engineering </p><p>  Abstract: Ceramic tool is one of main cutting tools for processing precisely. Because of its excellent performance and high ratio of property t

3、o price, it is in user’s good grace. This paper introduces the types of domestic cutting tool material, the choice of name and the methods of making rational use. </p><p>  Keywords: Ceramic tool; Duration o

4、f cutter; Use </p><p>  Ceramic tool is one of main cutting tools for processing precisely. Owing to the high hardness of ceramic(91-95HRA)and good wear-resistance that is four times higher than that of ceme

5、nted carbides, the duration of ceramic tool is several to tens times as long as cemented carbide tool’s. Ceramic can maintain higher hardness(80HRA)at temperatures as high as 1200 J and therefore can be used at much high

6、 temperatures. In has small affinity, low friction coefficient, high bonding resistance , prolife</p><p>  1. Choice of proper names and types of ceramic tool </p><p>  The types of domestic cut

7、ting tool ceramic include: puteAl2O3 ceramic, Al2O3-carbide ceramic, Al2O3-TiC-metal ceramic etc. Al2O3 ceramic, which contains more than 99.9% of Al2O3, is normally white, so it is called White Ceramic. P1(Originally na

8、med AM) produced by Chengdu Tool Research Institute belongs to this type. Because of its good wear resistance, Al2O3 ceramic is available for machining of gray cast iron and plain carbon steel. However, the disadvantages

9、 of low strength, bad thermal vibra</p><p>  Al2O3-carbide ceramic is obtained by adding carbide such as TiC, WC, Mo2C, TaC, NbC and Cr3C2 to Al2O3 and pressing. Among the carbides, what is used widest is Ti

10、C. On one hand, the property of this kind of ceramic is superior to pure Al2O3 ceramic, on the other hand, its machinability varies along with the content of TiC. Al2O3 carbide ceramic is mainly used to machine of harden

11、ed-steel and all sorts of wear-resisting cast iron. In our country, M 16(originally named T8), AG2, SG3 and SG4 are al</p><p>  Al2O3-TiC metal ceramic, which is called ceramic-metal, is made by adding bondi

12、ng metals (e. g. Ni, Mo) to Al2O3-TiC ceramic to improve its use range and bonding strength between Al2O3 and TiC, so it is useful for roughing. Our domestic ceramic-metal include AT6, LT35, LT55, M4, M5, M6 etc. AT6 con

13、tains 50% Al2O3, 40%TiC, 5%Ni, 4.5%Mo and 0.5% Mg. Its bending strength is 0.88-0.93 GPa, and hardness is 93.5-94.5 HRA. When machining of high-strength quenching and tempering steel, the cutting speed</p><p&g

14、t;  Al2O3-SiC ceramic is a high property ceramic that is made by adding 20%-30% SiC crystal whisker(an element crystal containing some fiber structure whose diameter is less than 0.6μm, its tensile strength is 7GPa and t

15、ensile elasticity coefficient is more than 700GPa). SiC crystal whisker, just like reinforcing bar in reinforced concrete, acts as obstacle that hinder and change the developing directions of crackle and greatly improve

16、its value of fracture toughness Kc to 9MPa (while the Kc of Al2O</p><p>  Si3N4 based ceramic which is developed in 1980’s, is a non-oxide ceramic. It is very hard (3000 to 5000 HV, is the material whose har

17、dness is second only to diamond, CBN and BC ) and it heat resistance is so good that it can cut at temperature as high as 1300℃-1400. Meanwhile, its strength (bending strength is 1℃-1.5 GPa) and toughness are better than

18、 Al2O3 based ceramic and its shock resistance is good, so it is especially available for big feed or interrupted cutting. Because of higher thermal</p><p>  Thus it can see. There are so many names and types

19、 of cutting tool ceramic that have their own characteristics and use range that we should choose the correct ceramics according to the property of workpiece material and the manufacturing characteristics, never believing

20、 some advertisements who boast their products all-powerful. Practice has proved that during machining of workpiece materials which contain A1 and Ti, it is easy to cause some unhealthy phenomenon such as diffusion wear,

21、chip-bondi</p><p>  2. Choice of proper cutting tool geometry and cutting conditions </p><p>  Besides of high-strength and new style of ceramic tool, it is necessary to choose proper cutting to

22、ol geometry and cutting conditions so that it can match the workpiece material. </p><p>  At present, although some new ceramics have made effective progress in strength and toughness, but being brittle mate

23、rial, they have lower bending strength and higher compressive strength of ceramic tool, negative tool orthogonal rake is usually used to process. In general, γ0=-5°--10°,tool orthogonal clearance α0=5°--12

24、°,inclination angle λs=0—5°,tool cutting edge angle κr=30°--75°.To strengthen cutting edge, negative first face is need to grind for, and the width of first face bγ1=0.1—0.3㎜, to</p><p> 

25、 Owing to good heat-resistance and wearability of ceramic tools. Its effect of cutting conditions to tool wear is far less than cemented carbide. During manufacturing, we should apply higher cutting speed and bigger dept

26、h as possible as we can to make full use of its good high-temperature property under the admission of machine tool power, rigidity of process system and strength of tool tip. For example, when Changzhou Diesel Engine Wor

27、k milled surfaces (Φ㎜ 160×134) of cylinder lid (HT200) with S</p><p>  3. The structure, tool grinding and check of ceramic tool </p><p>  At present, main structure of ceramic tool is inde

28、xable inserts tip. The shapes of tool tip include triangle, square, lozenge and circle. The location and clip of tool tip on shank must be firm and reliable, meanwhile the direction of clip force must make the tip keep c

29、lose to the location face. </p><p>  In order to ensure quality, during grinding , the ceramic tool must be clipped in special fixture on tool grinder. Now diamond grinding wheel with resin glue are widely u

30、sed to grind cutting tools. During rough grinding , the size number of wheel is 80/100—100/120, finish and polish grind use wheel of size number 170/200—325/400, consistency 50%--100%. During too grinding , the cutting c

31、onditions are: grind speed 20—30m/s,depth 0.005—0.002 P/double travel (rough grinding with bigger value, finis</p><p>  During checking ceramic tool, not only whether tool tip and tool spacer or shank are pr

32、essed together firmly needs checking, but the defects of cutting edge and quality of tip are ought to check as well. Practice has shown that the quality of tool tip influences the use to a great extent, so users must do

33、hardness and interrupted cutting experiment is: at first, random sample 3% to 5% from a batch of product, and then do HRA experiment by checking three points on per tip, at last, justify the qu</p><p>  4. C

34、hoice of proper equipments </p><p>  The machine tools using ceramic tools must have high stiffness, high power and high turning speed. Only so, its property can be make full use of and get good economic ben

35、efit. Besides, to avoid vibration and tool damages, high precise machine tool, dependable fixture or clamping apparatus are need. It must be pointed out that many equipments of factories can not satisfy the manufacturing

36、 requests of ceramic tool in production now. In the day to come, in pace with wide application of ceramic tool</p><p>  It must be explained that although some excellent ceramic tools are more expensive than

37、 cemented carbide tools, because of their good cutting property and high duration, cutting tool cost on per workpiece is far less than cemented carbide tool’s. Besides, it also can be used in turning and milling instead

38、of grinding, reduce working procedure. Judging from composite economic index, using ceramic tool is reasonable. To some high-efficiency equipments such as CNC machine tool, MC, FMS(FMC) and AL,</p><p><b&

39、gt;  譯文:</b></p><p><b>  陶瓷工具的合理使用</b></p><p>  ----W. C. Ye, F. Zhou淮陰工程設(shè)計(jì)學(xué)院 </p><p>  摘要:陶瓷工具是一種主要的精加工切割工具。由于它具有優(yōu)越的性能和高的性價(jià)比,所以它受到使用者的廣泛歡迎。這篇文章主要介紹國內(nèi)切削工具材料的類型,選擇的

40、名字和合理使用的方法。 </p><p>  陶瓷工具是一種主要的精加工切割工具。陶瓷在高硬度(91-95HRA)和耐磨性方面是水泥涂的碳化物的四倍多,陶瓷工具的使用壽命幾乎是水泥涂的碳化物的十倍。陶瓷在溫度高達(dá)1200J的同樣條件下比水泥涂的碳化物保持更高的硬度,因此它能夠被用在非常高的溫度下。在有小親合力、低摩擦系數(shù)、高接合抵抗、激增抵抗和很難形成一個(gè)建筑密集的邊緣的因素,所有這些因素使陶瓷工具表面質(zhì)量好象經(jīng)

41、過機(jī)械加工一樣,陶瓷工具和金剛石工具和CBN切割工具的切削性能是幾乎一樣的,然而陶瓷工具的價(jià)格遠(yuǎn)遠(yuǎn)低于金剛石工具和CBN切割工具。除一般生鐵和鋼以外,陶瓷工具還可以加工低切削性鋼,例如硬化鋼、高強(qiáng)度鋼、變冷的鋼和鎳合金。另外,它可能被用于車削和磨削代替研磨以提高生產(chǎn)效率。但是,陶瓷工具有更低的強(qiáng)度和更高的易碎性不利因素, 因此它長期以來主要被使用在精密加工中。在各種各樣的切割工具材料里, 它占領(lǐng)了較少比例。近年來, 由于原材料的純度和晶

42、粒尺寸成功的控制, 把碳化物和金屬通過熱壓加工(熱壓機(jī))和熱等壓加工(熱等壓機(jī))的方法結(jié)合到一起, 不僅彎曲強(qiáng)度被改進(jìn)到0.9 到1 GPa(甚至達(dá)到了1.3 到1.5 GPa, 等效與水泥</p><p>  1.給陶瓷工具選擇合適的名稱和類型 </p><p>  國內(nèi)切割工具陶瓷類型包括:純Al2O3陶瓷,Al2O3硬質(zhì)合金陶瓷,Al2O3-TiC金屬陶瓷等。Al2O3陶瓷包含Al2

43、O3超過99.9%,通常是白色,因此它被叫做白色陶瓷。P1(原來名字為AM)所有這類型產(chǎn)品都是由成都工具研究所生產(chǎn)。由于它的耐磨性好, Al2O3 陶瓷適合加工灰口鑄鐵和普通的碳鋼。但是, 低強(qiáng)度、差的熱防振和破裂韌性等不利因素使它容易破碎,因此它無法被使用在粗磨。然而冷壓加工卻是非常便宜。 </p><p>  Al2O3硬質(zhì)合金陶瓷的獲得是通過把碳化物例如TiC 、WC 、Mo2C 、TaC 、NbC 和Cr

44、3C2 添加到Al2O3中然后擠壓而成。在這些碳化物之中, TiC是被使用最廣泛的。一方面, 這種陶瓷的特性優(yōu)于純Al2O3陶瓷,另一方面, 它的可切削性變化是隨著TiC的含量變化的。Al2O3硬質(zhì)合金陶瓷是主要被用來加工硬化鋼和各種各樣的耐磨性生鐵。在我們國家,M16(原來的名字是T8),AG2,SG3和SG4都是屬于Al2O3硬質(zhì)合金陶瓷的成分,在它們之中,SG3和SG4包含WC。 </p><p>  Al

45、2O3-TiC金屬陶瓷被叫做陶瓷金屬, 主要是把接合金屬(即Ni, Mo) 加入到Al2O3-TiC 陶瓷中改進(jìn)它的使用范圍和Al2O3 和TiC的接合強(qiáng)度, 因此它對粗磨是有益的。我們國內(nèi)陶瓷金屬包括AT6 、LT35、LT55 、M4 、M5, M6 等。AT6 包含50% Al2O3 、40%TiC 、5%Ni 、4.5%Mo 和0.5% Mg。它的彎曲強(qiáng)度是0.88-0.93 GPa, 并且硬度是93.5-94.5 HRA 。當(dāng)

46、機(jī)器加工高強(qiáng)度淬火和回火鋼時(shí), 切削速度可能達(dá)到一般用水泥涂的碳化物工具的速度的一到三倍,而且它的使用壽命是一般水泥涂的碳化物工具的六到十倍。所以這種陶瓷適合在高速下切削灰口鑄鐵和耐磨鑄鐵。但是需要注意的是當(dāng)切削硬化鋼,使用Al2O3-TiC化合物陶瓷比使用Al2O3-TiC 金屬陶瓷的效果好。 </p><p>  Al2O3-SiC陶瓷是增加20%-30% SiC 晶須的一種高特性陶瓷 (一個(gè)晶體元素包含一些

47、纖維結(jié)構(gòu)直徑要遠(yuǎn)遠(yuǎn)小于0.6μm, 它的抗拉強(qiáng)度是7GPa 并且拉伸彈性系數(shù)是要遠(yuǎn)遠(yuǎn)超過700GPa) 。SiC晶須, 就象把障礙物加強(qiáng)在鋼筋混凝土上, 作為障礙物就是阻礙或改變裂紋的發(fā)展方向,并且極大地提高了破裂韌性Kc的值達(dá)到9 MPa (然而Al2O3化合物陶瓷的Kc值是4), 因此它也被叫做晶須加強(qiáng)陶瓷。這種陶瓷可以被用在切斷, 粗磨, 精磨, 刨削和鉆削, 它還對切削鎳合金、變冷的鋼和硬化鋼有幫助的, 但它的價(jià)格是一般Al2O

48、3陶瓷工具的多倍。我們國內(nèi)叫這種陶瓷的名字是AW9 和SG5 。 </p><p>  Si3N4陶瓷被開發(fā)在80 年代, 是一種非氧化物陶瓷。它是非常堅(jiān)硬(3000 到5000 HV, 是僅次于金剛石, CBN 和BC的第二堅(jiān)硬材料) 的材料并且它熱抵抗能力是非常的好以至于它可以在溫度高達(dá)1300℃-1400℃下進(jìn)行切削 。同時(shí), 它的強(qiáng)度(彎曲強(qiáng)度是1-1.5GPa) 并且韌性比Al2O3陶瓷好,它的抗震動能

49、力好, 因此它特別適合大量供給或用做切斷刀具。由于更高的導(dǎo)熱性、更低的熱膨脹系數(shù)和Si3N4的小彈性系數(shù), 它的熱沖擊抵抗力被明顯提高了。這種陶瓷適合加工鑄鐵、高溫合金和鎳合金。我們國內(nèi)給它們起的名字是FD01 、FD02 、FD03 、SM 、SM21 、TP4 、SC3, 等。在他們之中, 主要成分TP4 和 SC3是被叫做 Sialon 的Si3N4- Al2O3-Y2O3 。通常, Si3N4陶瓷并不比Al2O3化合物陶瓷好,

50、但是Si3O4新化合物陶瓷例如FD (國民發(fā)明第二等的價(jià)值) 由北京方達(dá)陶瓷高新技術(shù)公司發(fā)明的, SW21 由湖南長沙陶瓷公司生產(chǎn),這兩種陶瓷對于加工硬化鋼(60-68 HRC), 高錳鋼, 高鉻鋼和抗拉鋼是非常適合的, 因?yàn)樵赟W</p><p>  因此我們可以看到,有如此多名字和型號的陶瓷切削工具他們擁有各自的特點(diǎn)和使用范圍,我們可以根據(jù)工件材料的特性和制造特點(diǎn)選擇正確的陶瓷,沒必要相信一些廣告吹噓他們的產(chǎn)

51、品是全能的。實(shí)踐證明,在加工包含A1和Ti的工件材料時(shí),很容易引起某種對健康有害的現(xiàn)象,例如擴(kuò)散磨損、芯片接合和A1 涂層。由于許多陶瓷可以被用于同種材料的加工, 在實(shí)際生產(chǎn)過程中, 在確定最適合的陶瓷名字之前, 我們通常做些切削和比較的測試。</p><p>  2.選擇合適的切削工具的幾何角度和切削條件 </p><p>  除了陶瓷工具高強(qiáng)度和新樣式以外, 有必要選擇適當(dāng)?shù)那懈罟ぞ叩?/p>

52、幾何角度和切削情況以便它能夠與工件材料相匹配。當(dāng)前, 雖然一些新陶瓷已經(jīng)在強(qiáng)度和韌性上獲得了有效的進(jìn)展,但是作為易碎的材料, 陶瓷工具有更低彎曲強(qiáng)度和更高的耐壓強(qiáng)度,刀具陰面的直角傾斜一般用在處理過程中的??傊?,γ0=-5°--10°,后角α0=5°--12°刃傾角λs=0—5°,主偏角κr=30°--75°。為加強(qiáng)刀鋒, 陰性第一平面需要研磨, 第一平面的寬度bγ1

53、=0.1—0.3㎜,工具在第一平面上的前角γ01∠-20°。當(dāng)加工非常堅(jiān)硬的材料或在進(jìn)行材料切斷時(shí),就需要考慮刀具的幾何角度: bγ1=0.2--0.3㎜, γ01=-20°--30°,拐角處需要圓整其半徑為=0.5㎜, 但是帶有圓角的切削刀具在切削時(shí)就會增加切削阻力。所以當(dāng)加工韌性低、長而薄的工件時(shí),陰面是禁止使用的。 θr由于陶瓷工具具有耐熱性好和耐磨損性好的特點(diǎn),所以它的作用是陶瓷刀具在切削條件相同下

54、刀具磨損遠(yuǎn)遠(yuǎn)小于水泥涂的碳化物。在加工期間,在加工工具能承受范圍內(nèi)、嚴(yán)格按照系統(tǒng)步驟、刀尖強(qiáng)度承受范圍內(nèi)充分應(yīng)用陶瓷刀具可以在高溫下工作的優(yōu)點(diǎn)盡量提高切削速度、</p><p>  3.根據(jù)工具的結(jié)構(gòu)和研磨情況檢驗(yàn)陶瓷工具 </p><p>  當(dāng)前, 陶瓷工具主要結(jié)構(gòu)是在刀身前部鑲?cè)氲都?。整個(gè)刀尖形狀有三角形、正方形、菱形和圓形。用卡盤卡住刀尖的位置必須是牢固而可靠的,同時(shí)卡盤夾緊力方向

55、要使刀尖接近卡緊位置的正方向。為了保證質(zhì)量, 在研磨期間, 陶瓷工具必須在專用研磨機(jī)上被研磨掉一部分?,F(xiàn)在用樹脂膠結(jié)合的金剛石研磨輪子被廣泛使用在切削工具的研磨。在粗研磨期間,輪子的大小是80/100-100/120,磨光和磨光研磨用的輪子大小170/200-325/400, 連貫性能達(dá)到50% -- 100% 。在精研磨期間, 切削條件是: 研磨速度20-30m/s, 研磨深度0.005-0.002 P/double (粗磨用較大的值

56、,磨光和磨光研磨用較小的數(shù)值),進(jìn)給速度是10-15m/min 。 </p><p>  在檢查陶瓷工具時(shí), 無論刀尖和刀身或者卡盤被壓在一起是否牢固都需要檢查,而且刀鋒缺陷和刀尖質(zhì)量也應(yīng)該檢查。實(shí)踐表示, 刀尖在很大程度上影響刀具的使用, 因此使用者必需做堅(jiān)硬而且難加工的切削實(shí)驗(yàn): 起初, 隨意從一批產(chǎn)品中抽取樣品3% 到5%, 然后做HRA 實(shí)驗(yàn)來檢查每個(gè)刀尖上的三點(diǎn), 最后, 證明這批堅(jiān)硬而且難加工的切削實(shí)

57、驗(yàn)的質(zhì)量是:第一次隨機(jī)從一批產(chǎn)品中抽取樣品1% -- 3% ,然后在車床上試驗(yàn),工件可能是六角花鍵軸 (55-62HRC),切削條件應(yīng)該是: ν=100m/min, f=0.1mm/r, ap=0.5mm。切割工具的幾何角度也許是: γ0=-5°,αo=5°,λs=-5°, κr=45°--75°,bγ1=0.2ΦP, γ01=-20°, 工具圓角半徑rε=0.5mm 。在這些

58、情況下, 如果刀尖可以承受5000次沖擊而不破裂,然后我們就可以肯定這批產(chǎn)品是合格的。對于要使用在數(shù)控上的陶瓷工具,加工中心和自動生產(chǎn)線我們必須做檢查測試。 </p><p>  4.選擇適當(dāng)?shù)脑O(shè)備 </p><p>  機(jī)械工具使用陶瓷工具必須有高剛度、大功率和很高的轉(zhuǎn)動速度。只有這樣, 它的特性才能被充分利用和得到好的經(jīng)濟(jì)效益。除此之外, 盡量減少振動和工具損傷, 高精確的機(jī)械工具,

59、可靠的裝置或夾緊用具是非常必要的。必須被指出的是在許多工廠的設(shè)備根本無法滿足陶瓷工具生產(chǎn)的要求。在將來的某一天,隨著陶瓷工具的廣泛應(yīng)用,促使我們必須對機(jī)械工具制造業(yè)進(jìn)行改革和開發(fā)和然后進(jìn)一步促進(jìn)陶瓷工具的應(yīng)用。 </p><p>  值得解釋的是雖然一些好的陶瓷工具比用水泥涂的碳化物工具貴, 因?yàn)樗麄兊暮玫那邢魈匦院烷L時(shí)間的使用壽命,陶瓷工具在切削每個(gè)工件的損耗比用水泥涂的碳化物工具的損耗要低的多。除此以外,它還

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