Exceed strong cutting tool to machine medium applied analysis in hard turning

The mould steel of HRC47~58 of hardness of the cutting when the speed of 56m/min. When turning temperature is as high as 1500~1600 ° C still hardness is not reduced, do not oxidize, bit life is 4 times of general coating razor blade, and cost has 30% only, and adherent strength is good. Material of cutting tool of pottery and porcelain of material of pottery and porcelain comprises structure and suppress to be improved of craft ceaselessly as its, especially the progress of accept rice technology, make of cutting tool of pottery and porcelain add pliable but strong to become a possibility, be in before long in the future, pottery and porcelain may cause the 3rd revolution that cutting machines after afterwards high-speed steel, hard alloy. Cutting tool of pottery and porcelain has tall hardness (HRA91~95) , high strenth (bending strength is 750~1000MPa) , wearability is good, chemical stability is good, fight felt function good, coefficient of friction is low and the price is low wait for an advantage. Not only such, cutting tool of pottery and porcelain still has very tall high temperature hardness, the hardness when 1200 ° C achieves HRA80. When normal cutting, durability of cutting tool of pottery and porcelain is extremely tall, cutting rate can rise 2~5 than hard alloy times, suit finish machining and treatment of tall hardness material, high speed treatment particularly, but the hard steel of of all kinds temper by dipping in water that cutting hardness amounts to HRC65 and sclerosis are cast-iron wait. Have commonly usedly: Alumina base pottery and porcelain, nitrogen changes silicon radical pottery and porcelain, cermet and brilliant beard to add pottery and porcelain of pliable but strong. Alumina base cutting tool of pottery and porcelain has taller red rigid than hard alloy, blade of the cutting below position of high speed cutting won't produce plasticity to be out of shape commonly, but its intensity and tenacity are very low, to improve its tenacity, increase impact resistance can, can mix the compound of ZrO or TiC and TiN normally, another kind of method is to join pure metal or carborundum brilliant beard. Nitrogen changes silicon radical pottery and porcelain to divide red rigid tall beyond, still have good tenacity, with alumina base photograph of pottery and porcelain is compared, its defect is high temperature of easy when processing steel generation diffuses, aggravate cutting tool wears away, nitrogen changes silicon radical pottery and porcelain to basically apply at intermittent turning casting pig and milling casting pig. Cermet is one kind is base material with carbide, among them TiC is main horniness photograph (0.

5~2 μ M) , they pass Co or Ti binder union rises, it is a kind of as similar as hard alloy cutting tool, but it has inferior endophilicity, good attrition sex and better wearability. It can bear than groovy hard alloy higher cutting temperature, but the intensity when big feed of the tenacity when the impact resistance that lacks hard alloy, puissant cutting and low speed. Carry much research in recent years, improve and use the new technology that make, its bending strength and tenacity all had very big rise, the new-style cermet NX2525 that like Japan company of metal of 3 water chestnut develops and the cermet bit that Swedish Shan Dewei overcomes a company to develop taste CT series and series of coating cermet razor blade newly, the diameter that its grain organizes is petty to 1 μ M the following, bending strength and wearability all the cermet with common outclass, widened its use range greatly. Cubic nitrogen changes boron (the hardness of CBN)CBN and wearability are next to diamond, have wonderful high temperature hardness, compare with photograph of pottery and porcelain, its hear resistance and chemical stability are a bit poor, but impact strength and it is better to fight broken function. It applies to hard steel of temper by dipping in water extensively (casting pig of HRC ≥ 50) , pearlite, cold hard cast-iron the cutting treatment that waits with high temperature alloy, compare with photograph of hard alloy cutting tool, its cutting rate can raise an amount level. CBN content is high compound get together nitrogen of brilliant cubic metre changes boron (hardness of PCBN) cutting tool good, compressive strength reachs tall, wearability high impulse withstand tenacity is good, its defect is thermal stability difference and chemical laziness are low, apply to heat-resisting alloy, cast-iron the cutting treatment that fastens agglomeration metal with iron. Content of grain of the CBN in PCBN cutting tool is inferior, use pottery and porcelain to make binder, its hardness is inferior, but the characteristic with difference of thermal stability of before was being made up for one kind of material, chemical low laziness, the cutting of hard steel of applicable temper by dipping in water is machined. The leftover stress of pottery and porcelain and hard steel of temper by dipping in water of cutting of PCBN cutting tool is when cutting casting pig and hard steel of temper by dipping in water, can choose cutting tool of pottery and porcelain or CBN cutting tool, for this, should undertake cost effectiveness and treatment quality are analysed, choose in order to decide which kind of. Al2O3, Si3N4 and face of the knife after CBN cutting tool machines casting pig wear out condition, al2O3 of excel of function of cutting of material of PCBN cutting tool and Si3N4. But when hard steel of temper by dipping in water does type cutting, the cost of Al2O3 pottery and porcelain under PCBN material. Cutting tool of pottery and porcelain has good thermochemistry stability, but however not as good as the tenacity of PCBN cutting tool and hardness. Mix below under HRC60 in cutting hardness when using small feed, cutting tool of pottery and porcelain is better choice. PCBN cutting tool is comfortable the workpiece at HRC60 of cutting hardness prep above, when be being machined with high accuracy in automation treatment especially more applicable. Besides, in identical hind wear out condition leaves knife area, the stress of workpiece surface remains after cutting of PCBN cutting tool also compares cutting tool of pottery and porcelain to be stabilized relatively. Use PCBN cutting tool does hard steel of type cutting temper by dipping in water to still should follow the following principle: The condition allows to fall to choose to be cut greatly as far as possible in machine tool tigidity deep, the quantity of heat that such cutting areas generate makes metal of the area before blade local bate, can reduce PCBN cutting tool effectively wear away, in addition, in small cut deep when still should consider to use PCBN cutting tool to thermal conductivity is differred and make cutting area quantity of heat has not enough time to diffuse, cut an area to also can produce apparent metallic bate effect, reduce cutting blade wear away. Breast enhancement of film of key point of alkaline price of left flesh coming back recommends lavender reducing weight oil of essence of life goes blood from a wound of scar look line makeup brush which kinds of good segregation frost to wash his hands which kinds fluid is good of the bit structure that exceeds strong cutting tool and appearance of geometrical parameter razor blade and geometrical parameter reasonable and affirmatory distribute to filling. By cutting tool intensity character, the intensity of point of a knife of all sorts of bit appearance from arrive high low ordinal for: Lozenge of lozenge of lozenge of circle, 100 ° , square, 80 ° , triangle, 55 ° , 35 ° lozenge. After bit material make choice of, should choose intensity as far as possible tall bit figure. Hard turning razor blade also should choose as far as possible radius of big circular arc of point of a knife, with rough machining of circle and razor blade of radius of circular arc of big point of a knife, the radius of circular arc of point of a knife when finish machining is about 0.

8 μ M is controlled. Hard steel of temper by dipping in water cuts bits to be red and weak lace condition, brittleness is big, yi She is broken, not felt, quality of surface of cutting of hard steel of temper by dipping in water is high, do not produce the tumor that accumulate bits commonly, but cutting power is greater, especially radial cutting force is compared advocate cutting power is even great, so, cutting tool appropriate uses the part before losing (Go ≥ - 5 ° ) and bigger hind horn () of ° of Ao=10 ° ~15. Tool cutting edge angle depends on the machine tool is rigid, take ° of 45 ° ~60 commonly, in order to reduce workpiece and cutting tool flutter. The hardness of choice workpiece material that exceeds parameter of cutting of strong cutting tool and the requirement cutting parameter to machining complex is taller, its cutting speed should be jumped over small. Use the range of appropriate cutting speed that exceeds strong cutting tool to have hard turning precision work to be 80 ～ 200m/min, commonly used limits is used for 10 ～ 150m/min; cut material of tall hardness of deep or puissant interrupted cutting greatly, cut fast should maintain in 80 ～ 100m/min. Usually, cut deeply 0.

1 ～ 0.

Between 3mm. Process the work with exterior low surface roughness, optional small cutting deepness, but cannot too small, want appropriate. Feed can choose normally 0.

05 ～ 0.

Between 25mm/r, particular numerical value inspects exterior surface roughness to value and productivity ask and be decided. When Ra=0 of exterior surface roughness.

3 ～ 0.

When 4 μ M, use exceed strong cutting tool to undertake hard turning is gotten than using grinding economy much. Outside eliminating the cutting tool with logical choice to the requirement of machining complex, use exceed strong cutting tool to undertake hard turning does not have special requirement to lathe or turning center, if lathe or turning center stiffness are enough, and the precision that a demand can receive when processing flexible work and exterior surface roughness, can use at hard cutting. What operate to assure turning is smooth and successive, commonly used method is to use rigid clamp device and in cutting tool of the horn before waiting. If workpiece uses his in cutting master piece,fixed position, bearing is mixed rotate can hold quite smooth position, existing equipment can be used exceed strong cutting tool to undertake hard turning. Exceed strong cutting tool to be used in the application in hard turning exceed strong cutting tool to undertake hard turning, this technology passes development of ten years and promotion application, achieved enormous economic benefits and social beneficial result. With roller the industry such as treatment is below exemple, the specification surpasses the promotion application case of aborning of strong cutting tool. A lot of large roller enterprises already used home of roller treatment industry exceed strong cutting tool to be opposite cold hard the of all kinds roller such as hard steel of cast-iron, temper by dipping in water has barren car, thick car and car of essence of life, all obtained favorable beneficial result 7 raise treatment effect on average to lead 2 ～ 6 times, managing treatment man-hour and electric power 50% ～ 80% . If Wuhan is steely,company roller factory is HS60 ～ to hardness when the thick car of cold hard cast-iron roll of 80, half fine vehicle, cutting rate rose 3 times, every car a roller, managing electric power, man-hour expends more than 400 yuan, managing cutting tool expends nearly 100 yuan, obtained enormous economic benefits. If my school uses ～ of HRC58 of turning of FD22 cermet cutting tool when the roller of hard steel of 86CrMoV7 temper by dipping in water of 63 (Vc=60m/min, f=0.

2mm/r, ap=0.

8mm) , method of successive cutting roller amounts to Chan Ren face of the knife after 15000m(point of a knife wears away the VBmax=0 of the biggest width of the belt.

2mm) , satisfied the requirement that grinds with car generation. Trade of industrial pump treatment is current the 70% ～ of manufacturer of pump of domestic Cha oar 80% already used exceed strong cutting tool. Cha oar pump applies extensively at the industry such as mine, electric power, it is the product that is badly in need of domestic and internationally, its jacket, fender is HRC63 ～ the Cr15Mo3 of 67 is tall hard cast-iron. The past because all sorts of cutting tool hard turning this kind of material, be obliged to use the rough machining after anneal bate so, quench again next the craft of treatment. Use after exceeding strong cutting tool, realized sclerotic treatment smoothly, absolved anneal to quench again 2 working procedure, managing a large number of man-hour and electric power. The car machines an industry to wait for the treatment of the crankshaft in the industry, camshaft, transmission shaft in car, tractor, in the treatment of cutting tool, measure and equipment maintenance, classics regular meeting encounters the treatment difficult problem of hard work of temper by dipping in water. Be like our country plant of some engine car, need to undertake machining to bearing inner ring in equipment maintenance, bearing inner ring (material GCr15 steel) hardness is HRC60, inner ring diameter is F285mm, use grinding technology, grinding surplus is inhomogenous, ability needing 2h grinds good; and use first exceed strong cutting tool, become a core with respect to treatment with 45min only. Epilogue: Through old research and exploration, our country is in exceeded respect of strong cutting tool to obtain very great progress, but, the application that exceeds aborning of strong cutting tool is not wide still. The reason basically has the following sides: The effect understanding that produces enterprise, handlers to exceed strong cutting tool to undertake hard turning to using is insufficient, think generally hard data can grinding; thinks cutting tool cost is too high. The cutting tool cost with hard initial turning is higher than cutting tool of common hard alloy (if PCBN comparing is common hard metal is more than 10 times more precious) , but its apportion is returned than grinding in the cost on every spare parts low, and brought benefit is close friends many; is rightly than common hard alloy the standard that exceeds strong cutting tool to machine mechanism to study insufficient; exceeds strong cutting tool to machine can't coach production is carried out. Accordingly, besides strong to exceeding cutting tool treatment mechanism has thorough research outside, still must strengthen those who exceed strong cutting tool to machine knowledge to groom, successful experience demonstrates to reach strict operation standard, make this kind of efficient, clean treatment method applies morely at production actual. CNC Milling CNC Machining