The place in treatment of war industry product uses the new development of cutting tool material

W.

Taylor) and bosom of division of Cheng of smelt metal metalworking are special (M.

White) invented high-speed steel. The composition at that time is: C0.

67% , w18.

91% , cr5.

47% , mn0.

11% , v0.

29% , fe surplus. It can bear temperature of cutting of ℃ of 550 ～ 600, cutting is common rolled steel, can use 25 ～ the cutting speed of 30 M/min. The occurrence of high-speed steel, make cutting speed and cutting efficiency compared steel of carbolic element tool, alloy tool steel to rise respectively 4 times with 2.

5 times above. Arrive from 19 centuries end at the beginning of 20 centuries, high-speed steel ever made cutting level appeared a leap, make the mechanical manufacturing industry of the United States and world each country gets developing quickly, obtained enormous economic benefits. As level of human life, production rise, high-speed steel cutting tool already cannot satisfy the new requirement of tall treatment efficiency and tall treatment quality. People seeks the data of new-style cutting tool with higher performance. 20 time metaphase goes to 20 centuries at the beginning of 30 time, appeared tungsten is cobaltic kind with tungsten titanium cobalt kind hard alloy. Hardness of hard alloy normal temperature amounts to HRA 89 ～ 93, can bear the cutting temperature of above of ℃ of 800 ～ 900, the 3 ～ that cutting speed is high speed cutting tool 5 times, get applied gradually consequently. During the Second World War, as a result of large quantities of quantities, efficient the need that produces weapon, beautiful, flower, revive, heart each country already used hard alloy cutting tool partly: The escalate after World War II is used. After liberating, our country introduces a few hard alloy from Russia. 20 centuries after 50 time metaphase, begin to be produced by oneself and be used extensively. 20 centuries second half period, the mechanical function of workpiece material rises ceaselessly, the breed of the product and batch are added gradually much, the demand that machines precision rises increasingly, the structure of workpiece and appearance complication ceaselessly and diversification, raised newer, taller requirement to cutting tool, hard alloy cutting tool produced major effect in these new requirements. And hard alloy itself also has development, appeared a lot of new breed, its function rises ceaselessly. But hard alloy is more fragile, tenacity is insufficient, machinability far under high-speed steel, can use at lathe tool and milling cutter only in the begining, other cutting tool expands after, but cannot use at all cutting tool. because of such, high-speed steel can make the cutting tool of all sorts of types, occupational from beginning to end very large position. And high-speed steel also developed a lot of new breed, cutting function had compared with the common high-speed steel first very big rise. Arrive in recent years, high-speed steel and hard alloy still are data of uses at most two kinds of cutting tool, hard alloy a bit more than half. Through half century, hard alloy actually occupational so capacious position, it is people is in what what do not expect at the outset. Hard alloy cutting tool still cannot satisfy the requirement of the superprecision of material of workpiece of contemporary tall hardness, then newer cutting tool material appears in succession. 20 centuries 30 time appeared alumina pottery and porcelain, again nitrogen changes silicon pottery and porcelain later. Make a nitrogen of man-made cubic metre change boron and man-made to get together again with 60 time to 50 time stone of brilliant gold steel, their hardness substantially prep above is other cutting tool material. The hardness of pottery and porcelain is tallish at hard alloy, dan Jiren sex and machinability inferior at hard alloy. The place on put together is narrated, in 20 centuries, the rate that cutting tool material grows is gotten more quickly than in the past much. Let a hundred flowers blossom, get rid of the stale and bring forth the fresh, make a person dazzling, too many things to see. Its breed, type, amount and function all have than in the past substantially development, driving human material civilization to advance quickly. High-speed steel of material of 2 contemporary and new-style cutting tool is in contemporary cutting treatment, the function of high-speed steel is not quite advanced already, but good because of its stability, can accept form cutting, reason can in order to makes all sorts of cutting tool. In the high-speed steel in total wastage of cutting tool material nearly half. Traditional common high-speed steel is a delegate with W18Cr4V and W6Mo5Cr4V2. In tungsten department high-speed steel, divide MC, m2C, outside M23C, m6C is its main carbide, namely Fe3W3C and Fe4W2C. In tungsten department high-speed steel, m6C is Fe3(W, mo)3C and Fe4(W, mo)2C. In all high-speed steel, chromic content mark all maintains in 3.

5% ～ 4.

5% , it is the main element that increases high-speed steel temper by dipping in water to appear a gender. Cr23C6 is formed in steel. Vanadium content classification increases, the wearability of steel rises subsequently, but it is difficult to make cutting tool accepts blade to grind, and brittleness increases. The carbide of vanadium is VC and V4C3. Contain V 1% ～ the high-speed steel of 2% is used at most; V ＞ 3% person use lesser, and the cutting tool with avoid shaped complex form. After adding cobaltic element, can form exceed hard high-speed steel. Cobalt does not form carbide, but can rise quench temperature, enhance sclerotic result 2 times, raise high temperature hardness. American M42(110W1.

5Mo9.

The HSP-15(W9Mo3Cr4VCo10) of 5Cr4VCo8) and Sweden is the tall cobalt with good performance exceeds hard high-speed steel. China lacks cobaltic resource, cobaltic price is high. Developed those who do not have cobalt or little cobalt to exceed hard high-speed steel consequently. Co5Si(W12Mo3Cr4V3Co5Si) is the person that belong to little cobalt, the Co3N(W12Mo3Cr4VCo3N) of new development also is little cobalt, performance is good. Aluminous element can generate Al2O3, AlN in steel; And remove a hammer to plunge into action, prevent a fault, increased the hardness of material and strength thereby. China does not have cobaltic, little cobalt to exceed respect of hard high-speed steel in development, made larger contribution. Pulverous high-speed steel makes high-speed steel with pulverous metallurgy method, can eliminate carbide to slant analyse, raise the hardness of steel and tenacity, when vanadium content is high can better land blade is ground. Of pulverous high-speed steel cut can high-speed steel of function excel fusion. Home masters the skill of this respect. Abroad has product of pulverous high-speed steel, vanadium content is as high as 6% ～ 8% . On the matrix of high-speed steel, deposit of photograph of the regulating the flow of vital energy and removing obstruction to it that use thing (layer of material of wear-resisting of Fu of PVD) law besmear (be like TiN, the) such as TiAlN, can improve cutting tool life and treatment surface quality significantly, reduce cutting force. Cutting tool of high-speed steel of this kind of coating already got applied extensively. Hard alloy hard alloy is carbide (WC, TiC) pulverous metallurgy goods, normally cent is: The tungsten cobaltic series with cast-iron cutting (K kind, YG kind) , the tungsten titanium cobaltic series of cutting steel products (P kind, YT kind) , still have current series (M kind, YW kind) . New-style hard alloy has following 6 kinds. After the hard alloy that adds TaC and NbC is added, can effective land increases intensity of normal temperature hardness, high temperature and high temperature hardness, refine grain, rise fight the ability that diffuse and fights oxidation. In addition, still can increase fight plasticity metabolic ability. Form in alloy (W, ta, nb)C solid solution, WC of prep above of its chemistry stability and TiC. In new-style P, m, k kind form in hard alloy (W, ta, nb)C solid solution, WC of prep above of its chemistry stability and TiC. In new-style P, m, k kind in hard alloy, added TaC, NbC very much more. Fine grain and the hardness that alloy can raise after exceeding bead of fine grain hard alloy to refine and wearability, bending strength still can increase after adding cobaltic content appropriately. Average grain dimension is brand of common cutting tool and alloy 3 μ of 2 ～ M, fine grain alloy is 1 ～ 2 μ M, inferior imperceptible grain alloy is 0.

1 μ of 5 ～ M, exceed fine grain alloy for 0.

5 μ M is the following. In the past fine grain and exceed fine grain structure multi-purpose at K kind alloy, in recent years P kind, M kind alloy also develops to the direction that refines grain. Cutting tool of our country hard alloy already amounted to the level of fine grain of fine grain He Yawei. TiC radical and Ti(C, n) radical YT of hard alloy cermet, YG, in YW alloy, WC is bases, its content amounts to 65% ～ 97% , it is cohere agent with Co, tiC radical alloy is bases with TiC, occupy 60% ～ 80% above, contain a few WC only, make cohere lotion with Ni-Mo. With photograph of WC radical alloy is compared, the density of TiC radical alloy is small, hardness is taller, factor of the attrition when cutting steel products is minor, fight cohere and fight diffusing ability stronger, the fights model to change ability of Dan Jiren sex is a bit weak. Ti(C, n) radical alloy is had with the good point with TiC radical same alloy, dan Jiren sex and fight model to change TiC of ability prep above base alloy. Much in order to of this kind of alloy processes the rolled steel that did not quench. The hard alloy that adds rare-earth element adds the rare-earth element such as a few cerium, yttrium, increase the tenacity of alloy and bending strength effectively, wearability also has rise certainly. Because,this is rare-earth element aggrandizement horniness photograph and cohere photograph, purified crystal boundary, improved carbide solid solution to be opposite the wet sex of cohere photograph. This kind of alloy most apply to brand of rough machining cutting tool, yi Ke is used at semifinishing machining brand; In mine tool, top the hammer, model that pull silk uses foreground of broad development of the Yi Youan in hard alloy. Our country rare-earth element is resourceful, the research that adds rare land in hard alloy precedes somewhat. P, m, k kind alloy already developed a name that adds rare land. The method such as CVD of exterior coating hard alloy or PVD, in hard alloy razor blade apparently besmear Fu TiC, tiN, ti(C, n) , the layer such as Al2O3, form coating hard alloy. The function of mechanical, physics that is not coating hard alloy is the integral performance of horniness photograph and cohere photograph, reason its hardness and wearability the function under horniness photograph oneself. And the exterior hardness of hard alloy and wearability mirror little layer completely the function of the coating material oneself such as TiC, reason can improve cutting tool life and treatment efficiency, reduce cutting force, rise to already machined exterior quality. Come nearly 20 years, cutting tool of coating hard alloy had very great progress, in industry advanced country already was in 50% ～ can be occupied in dislocation cutting tool 60% above. The matrix of coating hard alloy still is the hard alloy of WC radical, the requirement has taller tenacity. As matrix different, this kind of alloy can make P kind, M kind or K kind hard alloy is used, and suitable scope is broader. Gradient hard alloy is the new breed that in recent years development rises, each composition can try to adjust according to need. Cent of material of cutting tool of pottery and porcelain of pottery and porcelain is 3 kinds. Alumina base pottery and porcelain joins TiC in Al2O3 matrix commonly, WC, siC, the composition such as TaC and ZrO2, become compound pottery and porcelain via heating up suppress. Hardness amounts to HRA 93 ～ 95, bending strength is amounted to 0.

7 ～ 0.

9GPa. To raise tenacity, chang Tian is added a few Co, the metal such as Ni. The nitrogen that nitrogen changes what silicon radical pottery and porcelain uses is Si3N4+TiC+Co changes silicon radical compound pottery and porcelain, its tenacity Al2O3 of constant prep above base pottery and porcelain. Hardness comparatives. Compound nitrogen changes silicon - composition of chemistry of alumina pottery and porcelain is Si3N4 77% about, al2O3 13% , y2O3 10% , hardness can amount to HV1800, bending strength can amount to  1.

20GPa. This kind of pottery and porcelain weighs Sai Along (Sialon) , alloy of optimum cutting high temperature and cast-iron. The hard alloy of excel of high temperature capability of pottery and porcelain, reason suits to be used at high speed cutting. Al2O3 base with Si3N4 base compound pottery and porcelain suits cutting temper by dipping in water hard steel, tall hard cast-iron reach general and cast-iron; Al2O3 base compound pottery and porcelain can effectively cutting not makings of hard steel of temper by dipping in water, and Si3N4 base cutting of pottery and porcelain is general rolled steel wears away in the begining rapid. Exceeding material of strong cutting tool to exceed hard data is to show diamond and cubic nitrogen change boron (CBN) . Their hardness is very more severalfold than tower above of material of other cutting tool. Diamond is the best material in nature, the hardness of CBN is next to diamond. In recent years, exceed material of strong cutting tool development is rapid. Cent of material of diamond cutting tool is 5 kinds. Natural diamond (ND) . Man-made gets together brilliant diamond (PCD) . It is raw material with black lead, high pressure of classics high temperature is made. Man-made gets together brilliant diamond is compound piece (PCD/CC) . It is base with hard alloy, the surface has a diamond (about 0.

5mm) , production method and PCD are identical. Cutting tool of diamond film coating (CD) . With CVD craft, in cutting tool surface besmear Fu makes an appointment with 10 ～ one layer the film of 25 μ M. Cutting tool of diamond thick film (TFD) . Yi Cai uses CVD technology, on another matrix besmear goes out 0.

The thick film of 2 Mm above, become thick film cut certain size again, next solder is used on hard alloy razor blade. The crystallization anisotropy of ND, must choose when the use that undertakes the knife is ground bring about appropriate way. Isotropy of making synthetic diamond, its hardness under ND, but intensity and ND of tenacity prep above. Diamond cutting tool can process stuff of the metal that be not iron and metalloid data effectively, if the nonferrous metal such as copper, aluminium reachs his,all sorts of alloy, pottery and porcelain, hard alloy, fiber and grain strengthen composite material, plastic, balata, black lead, glass and lumber to wait, but diamond avoid cuts steely etc metal of iron a group of things with common features. TFD has very good integral performance, it holds natural diamond and man-made concurrently to get together the advantage of brilliant diamond, as firm as base union, facilitate for many times grind again, reason has good applied value and development perspective. The production method of CBN and PCD or PCD/CC are similar. Change boron to be raw material with 6 nitrogen, high pressure of classics high temperature makes Cheng Jujing CBN or compound a CBN/CC. CBN basically is used at processing hard metal of hard steel of temper by dipping in water, tall hard cast-iron etc and metalloid data. With hard alloy or cutting of cutting tool of pottery and porcelain certain good fragile material, life is very brief, or can be competent far from, and those who exceed hard data to be opposite is easy to do. Diamond cutting tool can be executed to nonferrous metal exceed accurate cutting, it is its original part. The cutting tool data that the place of mankind of chemical part ancient time of material of 3 cutting tool uses is natural material more, the material that be like stone, natural diamond, still had used meteoric iron even. Arrive contemporary, material of great majority cutting tool uses artifical data, can assure a large number of supply, make quality of a material even, reliable.  reviews all sorts of cutting tool data, the raw material that removes making synthetic diamond is black lead (carbolic element) outside, other breed cannot leave carbide, nitride, oxide and boride. These compound have tall hardness, high melting point, high stretch standard to measure (see a table 1 ～ expresses 4) , this is the property that place of cutting tool stuff needs. Express the R(g/cm3)4 of density of TiCZrCHfCVCTaCNbCWC of property carbide property of all sorts of 1 carbide.

85 ～ 4.

936.

44 ～ 6.

9012.

20 ～ 12.

705.

36 ～ 5.

7714.

48 ～ 14.

657.

8215.

60 ～ 15.

℃ of Q(of 70 melting point) 32503175 ～ of 3180 ～ 38902810 ～ of 35403885 ～ 38803500 ～ of 28653740 ～ 2900 hardness of 38002627 ～ (32022800180024002400 stretch models measure 320026002533 ～ of HV)2900 ～ 448323 ～ of E (GPa)316 ～ 274371 ～ of 489433260 ～ 721 carbide of 389344536 ～ R(g/cm3)8 of property MO2CB4CSiCCr3C2Cr7C3Cr23C6Fe3C density.

92.

50 ～ 2.

543.

21 ～ 3.

226.

686.

926.

97 ～ 6.

℃ of Q(of 99- melting point) 24702200 ～ of 2 6902350 ～ 2700 decompose 1895178215181650 hardness (3500180018821663860 stretch models measure 37003000 ～ of HV)1 5002400 ～ 458345 ～ of E(GPa)544295 ～ 422380- - the R(g/cm3)5 of density of TiNZrNHfNVNTaNNbNWN of property carbide property that expresses all sorts of 2 nitride.

447.

3513.

946.

0814.

18.

26 ～ 8.

408.

℃ of Q(of 33 melting point) 32202930 ～ of 2900 ～ 33072050 ～ of 29803300 ～ 336020502420 hardness of 23602980 ～ (21001400 ～ of HV)1800 ～ 17001500106014001720 stretch models measure 16001500 ～ E (GPa)616---NB(of 587493- carbide property is cubic) Si3N4AlNCrNCr2NMo2NWN density R(g/cm3)3.

48 ～ 3.

493.

18 ～ 3.

193.

25 ～ 3.

306.

106.

518.

℃ of Q(of 04- melting point) 2720 ～ 3000 decompose 1900 decompose 2200 ～ 2300 decompose 1500- - 800 hardness (80002670 ～ of HV)7000 ～ model of 11881522 ～ 1629630- flexibility measures 12301000 ～ of 32601225 ～ E (GPa)720470281 ～ 352----Express the R(g/cm3)4 of density of TiO2ZrO2HfO2V2O5Ta2O5Nb2O5WO3Al2O3Cr2O3 of property carbide property of all sorts of 3 oxide.

246.

279.

683.

368.

734.

956.

473.

975.

℃ of Q(of 21 melting point) 188529002780 ～ of 1855 ～ 6851755 ～ of 2790670 ～ 2130205024202309 ～ of 18151473 ～ 2359 hardness (1500940 ～ of HV)10001300 ～ 270017202915 stretch models measure ～ of 1100-890 ～ 1290-2300 E (GPa)240 ～ 290250-----370- expresses the R(g/cm3)4 of density of TiB2ZrB2HfB2VB2TaB2NbB2W2B5CrB2FeBFe2B of property carbide property of all sorts of 4 boride.

386.

1710.

505.

06 ～ 5.

2812.

386.

9711.

05.

227.

157.

℃ of Q(of 34 melting point) 2790320032502400303730002370220016501410 hardness (34302230 ～ of HV)3310 ～ 34002797 ～ of 22742400 ～ 254026002650 ～ of 28132460 ～ 21801600 ～ of 26752020 ～ E (GPa)540350-273262650790215350290 of quantity of 1390 stretch models is like 17001290 ～ steel of carbolic element tool, its bases is Fe3C, alloy has compound carbide in tool steel, be like alloy cementite (Fe, cr)3C. There are more compound carbides in high-speed steel.

The horniness photograph of hard alloy basically is WCT and TiC, but often join Ta, nb wait for an element and fashion compound solid solution, and must use Co, ni for cohere material. The base material of pottery and porcelain is commonly used Al2O3 and Si3N4, but joined carbide, other oxide and nitride again, even boride. Cubic nitrogen changes boron is a kind of metalloid nitride. In cutting tool material, carbide is used at most. All sorts of metal carbide are divided 1 model, 2 model, 3 model, 6 model, 7 model and 23 model etc, namely MC(is like TiC, SZrC to wait) , M2C(is like Mo2C to wait) , M3C(is like Cr3C2, Fe3c to wait) , Mvalue="6">6C(is like Fe3(W, mo)3C6) , M7C(is like Cr7C3 to wait) wait for) like Cr23C6 with M23C(. Each model of carbide generate, all follow definite pattern. They also can form compound carbide, but its physics, mechanical nature examines exact data hard.  in recent years in, nitrogen, carbon and metal (one plant or 2 kinds) compound compound is in cutting tool coating is useful more. According to Baerchasi (the data of Balzer) coating company, listed the physics of material of a few kinds of coating, mechanical function, as a way of is referenced. The performance data name that expresses material of a few kinds of 5 coating is microscopical hardness (the dry attrition factor of HV) and steel is highest and applicable temperature (℃ ) color TiCN23000.

AlCrN32000 of 4400 blue gray.

TiAlN33000 of 351100 blue gray.

The sort of 4900 blue gray or violet gray carbide, nitride, oxide and boride is so numerous, very big effect was produced in develop and be used of cutting tool material. But already was used and be being returned heply for people place is among them minority only, most and outstanding all application, this one circumstance is expressed from watch 1~ 5 in can see. Accordingly, when people is developing material of new cutting tool, in the Shang Youxuan on chemical constituent choose leeway and very great potential can be dug. Of course, the compound that lists in the watch is not useful the likelihood that go up, because cannot consider corporeal performance only, still answer the element such as attend to resource, price and craft. 4 cutting tool of  of material and workpiece material match war industry product multi-purpose difficult treatment material, if hard steel of steel of high strenth, extra high strength, tall manganese steel, temper by dipping in water is mixed cold hard alloy of alloy of cast-iron, stainless steel, high temperature, titanium, composite material. The mechanical, physics of two respects material and chemical function must get cutting tool, workpiece match reasonably, cutting process square can on the rails, acquire normal cutting tool life; Otherwise, cutting tool may wear away quickly, cutting tool life is very brief. For example, the workpiece stuff with expensive hardness, must be machined with stronger cutting tool; Hardness of high-speed steel cutting tool is insufficient, cannot use cutting oil hard steel and cold hard cast-iron, hard alloy and cutting tool of pottery and porcelain can be competent, CBN cutting tool is much better. Process hard fragile data, ask cutting tool has very tall hardness not only, still ask to high stretch standard is measured, otherwise blade ministry is propped up hard. With hard alloy cutting tool hard steel of treatment temper by dipping in water reachs other hard fragile data, must introduce stretch model the volume is higher (WC composition is more) K kind or M kind brand. Above is mechanical function match. The normal temperature that considers cutting tool data not only is mechanical function, still should consider its high temperature capability. When the work that processes thermal conductivity difference, should use the tool with better thermal conductivity, in order to make heat in metal cutting is able to come out. Drop cutting temperature thereby. This is the example that physical sex can match. If the chemical element in material of both sides of workpiece, cutting tool has easy chemical combination, mutual hair to biochemistry learns action or diffuse action person, should try evasive. For example, the metallic material that contains titanium -- stainless steel of titanium alloy, high temperature alloy, austenite, the cutting tool that cannot use the element that contain titanium undertakes cutting. That is to say, p kind hard alloy, TiC radical and Ti(C, n) radical hard alloy, coating hard alloy (most coating material contains titanium) all cannot use; Should use K kind hard alloy or high-speed steel. Data of every treatment plasticity produces long cut bits and with before the person that knife range occurs clash, should special attention knife - of element of bits both sides diffuse each other, material of hard steel of temper by dipping in water of cause treatment blame ought to use P kind hard alloy or Al2O3 base pottery and porcelain, and cannot use K kind alloy and Si3N4 base pottery and porcelain. Diamond is when above of 600~700 ℃ translate into black lead, fe element will remove catalysis and quicken this kind to change, reason diamond cutting tool cannot process steely data. CBN suits to process iron and steel most, but can undertake doing cutting only, fluid of water radical cutting will make below high temperature CBN is decomposed. These are the example that chemical function matchs. Chemistry undertakes commonly below microtherm condition slow, high temperature issues aggravate. Mechanical, physics, chemistry is combined influence sometimes and be mutual correlation, still understand insufficient development to the mechanism of chemistry especially to their rule, remain to study further. 5 epilogue workpiece and cutting tool both sides are alternant progress, mutual promote, become the historical law that cutting technology develops ahead ceaselessly. Before 20 centuries half, the time that second half period is great progress of high-speed steel, hard alloy respectively. In nearly 50 years, hard alloy improves the performance of oneself ceaselessly, developed a lot of new breed, in the domain from high-speed steel occupational big position, become current dosage to exceed the cutting tool material of the half, this is in those days people place fails to estimate. Predict 21 centuries, the scope of application of hard alloy will expand further; High-speed steel depends on the advantage of its integral performance, will still occupy stated position. As a result of the reason of resource, price and function, material of pottery and porcelain also will get developing, replace cutting tool of one part hard alloy. However, because the cutting function of pottery and porcelain and hard alloy photograph are compared, difference is not so tremendous, add the inadequacy of its intensity, tenacity and machinability, the development of cutting tool of prospective pottery and porcelain won't replace high-speed steel like past hard alloy swift and violent in that way. Exceed hard data to will receive more application. The development cycle of material of new cutting tool will be shorter and shorter, of new breed, new name roll out will faster and faster. In progress of cutting tool material, hardness, wearability and intensity, tenacity hard give attention to two or morethings still is main contradiction. Go out to have the intensity of high-speed steel, hard alloy and tenacity already in the development in 21 centuries likely, have the cutting tool stuff of the hardness that exceeds hard data and wearability again. All sorts of coating cutting tool and complex structure can overcome afore-mentioned contradiction on due process, reason has development perspective extremely. In future, cutting tool material will accept workpiece one party and the challenge with production newer, grimmer system. The occurrence of new breed, change that takes specific gravity severally and they compete each other and complementary the situation that fill, the characteristic that makes progress of material of prospective cutting tool. Current, carbide, nitride, oxide and boride are the main body composition of cutting tool material. Get together for man-made with black lead synthesis brilliant diamond already jumped out this circle. In recent years Wuhan university uses RF-PECVD law to besmear on twist drill Fu C3N4 is filmy, velar hardness is adjacent exceed hard data, broach service life rises greatly. In 21 centuries, cutting tool material will have unexpected new leap development. CNC Milling CNC Machining