Cutting cutting tool matchs research with what machine an object

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Summary: According to studying the current situation domestic and internationally, as reasonable as what machine an object to cutting cutting tool matched a problem to undertake be commentinged integratedly. The progress of material of 1 foreword cutting tool is promoting the development of cutting processing technique greatly. Mix to diamond from cutting tool of cutting tool of steel of carbolic element tool, high-speed steel cutting tool, hard alloy cutting tool, pottery and porcelain cubic nitrogen turns boracic cutting tool, the every time innovation of cutting tool material machines course of study to bring revolution to cutting almost. Come nearly 30 years especially, the cutting tool data that processes the mainest essential factor as cutting got developing quickly, use all sorts of high pure the data of new-style cutting tool that exceeds fine oxide, nitride, carbide, boride and alloying element to make is constant emerge in large numbers, the physical machinery function of material and cutting processability can have very big rise, applied limits also expands ceaselessly. The material of new-style cutting tool of development if cutting tool of compound cutting tool, layer of accept Mi Tu, brilliant must add accept rice material of cutting tool of pottery and porcelain of pliable but strong, gradient function cutting tool for contemporary cutting treatment industry offerred new alternative. At present the uses extensively cutting tool data on international basically has: High-speed steel cutting tool, hard alloy cutting tool, exceed strong cutting tool to wait, the brand of cutting tool material amounts to on 1000 kinds. As the development of science and technology, also raised taller and taller requirement to project material. New-style metal or material of material of all sorts of light qualitative strong pliable but strong, new-style aerospace material, nuclear energy material, composite material, biology, function material, accept rice material, rare earth material, metalloid material the application that wait is increasingly wide. Face so phyletic and various workpiece data, how to choose cutting tool material correctly to undertake cutting is machined, in order to raise cutting treatment productivity, reduce finished cost and reduce resource to use up, it is the problem that a need takes seriously highly. Long-term since, the means of material of cutting tool of option of company of domestic and international machining is cut with trying traditionally law and consult before experience is given priority to. When processing some one new-style data, often need to use a variety of cutting tool material to undertake cutting experiments repetition, study those who analyse cutting tool to wear away, damaged means and its reason, through choosing material of first-rate cutting tool from which quite. Blindness of this kind of method is big, create a large number of waste of manpower, financial capacity and resource. And a lot of companies choose cutting tool according to experience, often cannot choose material of optimal cutting tool, cause cutting to machine productivity finished cost of low, cutting increases, resource of cutting tool material (especially a few precious alloying element) wasteful and serious. The cutting tool material of each breed has its specific size range of pipe bent, can get used to certain workpiece material and cutting speed limits only. Different cutting tool or life of the cutting tool when akin cutting tool processes different workpiece data often can be put in very big difference, because this so called all-purpose cutting tool is nonexistent. "Labour desire be apt to its thing, surely first benefit its implement " this China logion already became domestic and international consensus. So, reasonable choosing cutting tool is the key that undertakes cutting is machined successfully. The cutting tool material of each breed has his optimal treatment object, what be put in cutting cutting tool and treatment object namely is reasonable match a question. Cutting cutting tool matchs with what machine an object basically is the mechanical function that points to both, physics function and chemical function match, in order to obtain the longest cutting tool life and the biggest cutting treatment productivity. Combine the research that the author already had, the article will be right cutting cutting tool is as reasonable as what machine an object match undertake be commentinged integratedly. 2 cutting cutting tool and the mechanical function that machine an object match cutting cutting tool and the mechanical function that machine an object basically is the mechanical performance data such as the intensity that points to cutting tool and workpiece material, tenacity, hardness should match each other. The cutting tool of different and mechanical function (like high-speed steel cutting tool, hard alloy cutting tool, exceed strong cutting tool to wait) the workpiece stuff that fits treatment differs somewhat. Normally, the hardness of cutting tool material must the hardness of material of prep above workpiece, cutting tool hardness asks to be in commonly 60HRC above. The workpiece data of tall hardness must be machined with the cutting tool of taller hardness, if cubic nitrogen changes boron and cutting tool of pottery and porcelain to be able to be competent hard steel of temper by dipping in water (steel of 45 ～ 65HRC) , bearing (60 ～ 62HRC) , high-speed steel (steel of HRC>62) , tool (57 ～ 60HRC) and cold hard cast-iron the fine vehicle treatment that waits for material, can come true to be ground with car generation. In addition, the hardness of cutting tool material is taller, its wearability is better. Have admirable high temperature the cutting tool of mechanical function suits treatment of high speed cutting particularly. The cutting rate that high speed cutting uses is more severalfold than groovy cutting tower above even ten times, cutting temperature is very accordingly high. For this, material of cutting tool of the requirement when high speed cutting should have good room temperature not only mechanical function, still should have exceedingly good high temperature mechanical function, and its high temperature is mechanical function is more mechanical than room temperature function is more main. Although the room temperature intensity of cutting tool of pottery and porcelain is inferior, but when temperature is elevatory, its bending strength is reduced very few. When amounting to 1000 ℃ to control like cutting temperature, when value of its bending strength compares room temperature only slightly low. The high temperature capability with admirable cutting tool of pottery and porcelain makes his comfortable at high speed cutting, permission cutting rate is higher than hard alloy 2 ～ 10 times. The cutting tool of Sialon pottery and porcelain of high temperature tall hardness also can regard high temperature cutting as cutting tool. Hard alloy in temperature prep above the because of felt photograph molten hardness when 500 ℃ drops quickly, so unwell at using as cutting tool of high temperature cutting. The hardness of all sorts of cutting tool material sees a picture along with the change of temperature 1. Graph the hardness of all sorts of 1 cutting tool material decides strong fragile cutting tool along with the change of temperature (like hard alloy and pottery and porcelain) tatty is main the element is his mechanical function. The research of the person such as Evans makes clear, the brittleness with hard fragile inherent data is to bring about its tatty main reason. Accordingly, the hardness that he built material of cutting tool of pottery and porcelain, rupture the mechanical function such as tenacity wears away with its characteristic relation, namely in type of V ∝ 1nP5/4S1KIC3/4H½(1) , v is wear away bulk, KIC is rupture tenacity, h is hardness, n is the number that wear bead, the force that P is perpendicular action to go up at wearing bead. The abrasive that the person such as Wayne waits for cutting tool of pottery and porcelain to Al2O3, Al2O3/TiC and Al2O3/TiB2 wears away character had a test, the result makes clear: Formulary (1) can be qualitative reflect cutting tool data wear away the relation of as mechanical as its function, but theoretical calculation result and real measured value have certain difference, main reason is type (the impact that micromechanism of material of pottery and porcelain did not consider in 1) . The physical performance that 3 cutting cutting tool and the physical function that machine an object match cutting cutting tool and treatment target matchs basically is the melting point that points to cutting tool and workpiece material, stretch model quantity, coefficient of thermal conductivity, hot coefficient of expansion, heatproof. The cutting tool that has different physics property (the diamond cutting tool that the cutting tool of pottery and porcelain that if tall heat conduction is mixed,the high-speed steel cutting tool of low melting point, Gao Rong is nodded and low heat bilges, tall heat conduction and low heat bilge) the workpiece stuff that fits treatment differs somewhat. When the work that processes thermal conductivity difference, should use the cutting tool with better thermal conductivity, drop cutting temperature with making heat in metal cutting can come out quickly. 1 what the coefficient of thermal conductivity of diamond is hard alloy.

5 ～ 9 times, the 2 ～ that are copper 6 times, because coefficient of thermal conductivity and emissivity are tall, heat in metal cutting comes loose easily piece, temperature of cutting part of reason cutting tool is low. The hot coefficient of expansion of diamond is smaller than hard alloy severalfold, it is the 1/10 of high-speed steel about, because this diamond cutting tool won't produce very big heat to be out of shape, this very tall to dimension precision requirement accurate treatment is attached most importance to especially for cutting tool should. The thermal conductivity that cubic nitrogen changes boron although not as good as diamond, but however greatly prep above high-speed steel and hard alloy. Follow cutting temperature rise, the coefficient of thermal conductivity of CBN cutting tool increases gradually, can make point of a knife is in cutting temperature to reduce, of the precision of the treatment when diffusing to wear away and be helpful for high speed finish machining that reduces cutting tool rise. The hear resistance of CBN but achieve 1400 ～ 1500 ℃ , the hear resistance that compares diamond (800 ℃ of 700 ～ ) almost one times taller. When the cutting rate that uses as a result of place of high speed cutting compares groovy cutting tall severalfold even ten times, cutting temperature is very high, because the invalidation of cutting tool of cutting of this high speed basically depends on the hot property of cutting tool material (the melting point that includes cutting tool, hear resistance, fight oxidisability, high temperature the) such as mechanical function, heatproof concussion function. High speed dry cutting, high speed hard cutting and the highest cutting speed that high speed machines black metal basically get the hear resistance of material of cutting tool of be confined to, the melting point because of material of this requirement cutting tool tall, thermal conductivity temperature of good, oxidation tall, hear resistance is good, heatproof concussion sex is strong. When if high speed is treatment steel, cast-iron,waiting for black metal, highest cutting speed can achieve the 1/3 ～ 1/5 when machining aluminium alloy only, its reason is heat in metal cutting makes happening of point of a knife heats up damaged easily. In high speed cutting low thermal conductivity reachs tall hardness material (like titanium alloy, heat-resisting alloy steel of nickel radical alloy, tall hardness) when, easy form dentate cut bits, and what ply can arise to change in process of high speed milling is intermittent cut bits, they can bring about the thermal stress inside cutting tool produce high-frequency cycle to change, quicken cutting tool thereby wear away. 4 cutting cutting tool and the chemical function that machine an object match cutting tool wearing away is mechanical wear and chemistry wear away the result of integrated action. Mechanical wear basically includes abrasive to wear away, felt wears away, plasticity wears away and microcosmic rupture etc. Chemistry wears away basically is chemical and the chemical reaction that shows the constituent that issues cutting tool data in high temperature and workpiece material happen, deliquescent and of the element between cutting tool and workpiece diffuse etc. Already some considers to make clear: Closely related the wears away to be machined with place workpiece material when cutting tool cutting is machined and cutting condition, when the workpiece material that below different cutting condition treatment differs, take dominant place wear away the mechanism differs somewhat. If be when low speed cutting, because temperature is inferior, its wear away the mechanism often is behaved wear away for abrasive; And the chemical reaction that causes in the high temperature when high speed cutting, oxidation wears away and diffuse wear away to take dominant place. Because workpiece material hardness falls to drop somewhat in high temperature, consequently abrasive wears away to be reduced gradually, if pursue,2 are shown. Chemistry wears away with cutting temperature closely related, its expression is a graph when cutting of 2 cutting tool is machined wear away in K= Aexp-[E/(RT)](2) type, k is chemical wear extent, a is constant, cutting tool and workpiece material combine the activation energy of a decision for E, t is absolutely temperature, r is gas constant. Cutting cutting tool and the chemical function that machine an object match basically is the chemical endophilicity that points to cutting tool and workpiece material, chemical reaction, diffuse, felt and deliquescent wait for chemical performance data to should match each other. The cutting tool that has different constituent (like high-speed steel cutting tool, hard alloy cutting tool, exceed strong cutting tool to wait) the workpiece stuff that fits treatment differs somewhat. When the elemental chemistry in cutting tool and workpiece endophilicity is strong (reaction of easy generation chemistry, mutual felt or diffuse) when, should try evasive. If contain SiC grain or the cutting tool material that SiC brilliant needs,good cutting performance is shown when machining nickel radical alloy, but processing steel when cutting tool material happens to wear away quickly however. Because SiC falls very easily to produce chemical reaction with the Fe in workpiece material in action of cutting high temperature,this is, the chemical laziness that its react type is pottery and porcelain of 4Fe+SiC → FeSi+Fe3C(3)Al2O3 is more than TiC and WC. Although be when fused temperature, al2O3 and steel also do not have chemical reaction; Next, al2O3 wants than WC in the deliquescent rate in iron low 4 ～ 5 times. Accordingly, cutting processes steel when, of cutting tool of Al2O3 pottery and porcelain diffuse wear away very small. Additional, aluminous element is contained in Al2O3 pottery and porcelain, bigger chemical affinity exists when accordingly cutting tool of Al2O3 pottery and porcelain is machining aluminium and aluminium alloy, appear very easily to bigger felt wears away and diffuse wear away. Al2O3/TiC and Al2O3(/W, the pottery and porcelain such as Ti)C all contains aluminium and titanium element in cutting tool, bigger chemical affinity also exists when machining titanium and titanium alloy, aluminium and aluminium alloy with cutting tool of this kind of pottery and porcelain, because this should avoid,machine aluminous, titanium and its alloy with this kind of cutting tool. Si3N4 base cutting tool of pottery and porcelain is in cast-iron and the cutting of nickel radical alloy gets applied extensively in treatment. Si3N4 base abrasive basically happens to wear away when cutting of high speed of pottery and porcelain is cast-iron, and chemistry basically happens to wear away when steel of carbon of high speed cutting. Chemistry wears away what itself holds proportion in the total wear extent of cutting tool of pottery and porcelain general not big, but main effect depends on chemical tatty it can be big big aggravate mechanical wear, if chemistry is deliquescent,reach diffuse action can cause strength of surface of pottery and porcelain abate, the felt between aggravate cutting tool and workpiece, bring about thereby serious felt wears away and microcosmic rupture wear away. Of the cutting tool when using steel of AISI1045 of cutting of cutting tool of Si3N4 pottery and porcelain wear away when comparing cutting casting pig get high much. Of the element such as the Fe between the workpiece when cutting is cast-iron and cutting tool, Si diffuse each other action should compare cutting steel when small much. Between because presence is larger between Si3N4, Fe chemical affinity and Si and Fe diffuse each other, because this Si3N4 cutting tool is unwell,wait for material at pure iron of high speed cutting and carbolic steel, because the high temperature of the generation when high speed cutting meets what the chemistry between Si3N4 of big big aggravate and this kind of workpiece reachs an element diffuse, bring about aggravate of tatty of Si3N4 cutting tool. Accordingly, when processing steel, of cutting tool of Si3N4 pottery and porcelain wear away to basically be concerned with the chemistry between cutting tool and workpiece. Diamond cutting tool agrees with machine metalloid material, nonferrous metal and its alloy. When cutting nonferrous metal, the life of PCD cutting tool is hard alloy cutting tool a few times even hundreds of times. Silicon is contained in treatment the volume is higher (10% above) when aluminium alloy, the 10 ～ that the durability of diamond cutting tool is hard alloy 50 times. The thermal stability of diamond is poorer, its hardness can be lost when cutting temperature achieves 800 ℃ ; Diamond cutting tool does not agree with treatment is steely kind of material, because of diamond and iron a group of things with common features there is very strong chemical affinity between the element, iron atom falls to make easily with carbolic atom interaction in high temperature structure of black lead of its translate into, cutting tool damages extremely easily. Cubic nitrogen changes boracic hardness to be next to diamond, and have very tall thermal stability, can bear the cutting temperature of 1200 ℃ above. Its are the biggest the advantage is to be below high temperature (1300 ℃ of 1200 ～ ) won't with metal of iron a group of things with common features produces chemical reaction. The chemical laziness of CBN is big, mix to acid in medium of neuter, reducing gas alkaline have very tall chemical stability, with element of iron a group of things with common features is when 1300 ℃ of 1200 ～ also do not have chemistry. Consider to make clear: CBN and the felt of all sorts of material and diffuse effect is less than hard alloy much. CBN is had very tall fight oxidation ability, also won't produce oxidation phenomenon when 1000 ℃ . Because CBN is had,exceed stability of strong character, high fever, tall chemical stability and cause wide attention. In high speed cutting cast-iron when, can use CBN cutting tool. But the metallographic of cast organizes pair of CBN cutting tool choose have certain effect, when the cast that gives priority to in order to be more than the cutting rate treatment of 500m/min with pearlite, can use CBN cutting tool; When cast is given priority to with ferrite, because diffuse tatty reason, cutting tool of unfavorable use CBN, and should use treatment of cutting tool of pottery and porcelain. The place on 5 conclusion put together is narrated, the cutting tool of each breed has its specific size range of pipe bent. Cutting cutting tool and function of the matchs to basically point to both mechanical, physics that machines an object and chemistry match each other, in order to obtain the longest cutting tool life and the biggest cutting treatment productivity. Cutting cutting tool and the mechanical function that machine an object match basically is to point to the mechanical performance data such as the intensity of cutting tool and workpiece material, tenacity and hardness to should match each other. Cutting cutting tool and the physical function that machine an object match basically is the physics such as function of quantity of the melting point that points to cutting tool and workpiece material, stretch model, coefficient of thermal conductivity, hot coefficient of expansion, heatproof concussion performance data should match each other. Cutting cutting tool and the chemical function that machine an object match basically is to point to cutting tool and workpiece material chemistry endophilicity, chemical reaction, diffuse, felt and deliquescent wait for chemical performance data to should match each other. In applying actually, the workpiece data that should process according to place chooses the cutting tool material that matchs each other. Build database of cutting cutting tool and function of the mechanical, physics that machines an object and chemistry, the mechanical, physics that establishs cutting cutting tool and treatment target and chemical function match relation model, and scale of computer of have the aid of goes out to differ with cutting of different material cutting tool of the cutting tool when material workpiece and workpiece material match relation a collection of illustrative plates, realize the standardization that cutting tool material chooses and rationalize, will be henceforth a when cutting treatment studies main task. CNC Milling CNC Machining