Kuburikidza nekuongorora kwekuyedza kwesarudzo yekushandisa,machine
parameters and tool angles, the best solution for mirror surface machine of copper alloy shaped grooves is finally arrived at, providing a theoretical basis and research foundation for improving the surface machine quality of copper alloy parts.
With the improvement of the use performance of scientific and technological products and the growth of the use cycle, manufacturing enterprises have put forward higher requirements for the dimensional accuracy, geometric tolerance and surface roughness of product parts. In ultra-precision machine, in order to ensure the roughness of the parts, most of them use grinding processing technology. However, copper alloy is a non-ferrous metal, and the material characteristics of non-ferrous metal determine that grinding processing is not suitable, and turning processing by lathe is appropriate. By analyzing the causes of the formation of surface roughness and combining with the actual processing experience, a set of turning methods to improve the surface roughness of the parts is summarized.
2Chikamu chimiro chimiro
A model of copper alloy material parts structure as shown in Figure 1, according to the design requirements, V-shaped groove and the inner circle coaxiality requirements φ0.01mm, surface roughness value Ra = 0.2μm. material for brass H62, the material has good mechanical properties, good plasticity, good turning performance, but there are sticky tool. The current existing machine capacity of the factory makes the surface roughness value Ra of the part reach 0.8μm, which cannot meet the design requirements. Therefore, the processing technology of V-groove needs to be studied in depth to explore a suitable processing method to meet the production requirements.
Mufananidzo 1 Mhangura chiwanikwa chikamu chimiro
3.1 Mirror machine technology turning and forming
(1) Tool The tool material currently used in the factory is mainly cemented carbide. Cemented carbide is made of tungsten-cobalt class (WC), tungsten-cobalt-titanium (WC-TiC), tungsten-titanium-tantalum (niobium) cobalt (WC-TiC-TaC) and other refractory metal carbides, which are pressed and sintered by powder metallurgical methods with metal binder Co (cobalt) or Ni (nickel). Cemented carbide has high hardness, wear resistance, better strength and toughness, heat resistance, corrosion resistance and a series of excellent properties, can be used for processing non-ferrous metals. It can be used for rough machine when processing copper alloy V-groove.
In the field of non-ferrous metal mirror processing, diamond tools are one of the more commonly used. Diamond tools have the advantages of extremely high hardness and wear resistance, low friction coefficient, high elastic modulus, high thermal conductivity and low thermal expansion coefficient, as well as low affinity with non-ferrous metals, and not easy to produce chip tumors. In addition, due to the diamond elastic modulus, cutting cutting edge sharp, edge deformation is small, the non-ferrous metal extrusion deformation of the cutting is small, can make the cutting process in a small deformation to complete, so you can improve the quality of surface processing. Diamond tools mainly have: thin film coated tools, thick film diamond welding tools, diamond sintered tools and single crystal diamond tools. The copper alloy V-groove with an angle of 60° needs to be studied for the selection of tool angle in order to avoid interference during machine. Considering the machine cost as well as the test convenience, the machine clamp tool is used. As shown in Figure 2 and Figure 3, 35° and 45° inserts were used, and two types of fixtures were tested.
Fig. 2 35 ° inoisa Mutsara. 3 45 ° inoisa
(2) Machining parameters Machining parameters directly affect the surface roughness. In mirror machine, the spindle speed will become the main factor affecting the surface roughness when the tool feed is reduced below a certain value. When the spindle speed is kept constant, the surface roughness increases rapidly when the turning depth is less than a certain value, while when it is greater than this value, the surface roughness shows an approximately linear increasing trend. The most appropriate depth of cut needs to be found for a particular material. Therefore, different process parameters need to be selected for experimental verification.
3.2 Kugadzira maV-grooves vachishandisa machira vhiri yekupolaya tekinoroji
Ikozvino fekitori inogadzira conductive mhete V-yakaumbwa groove, iyo yepamusoro roughness kukosha inogona kusvika Ra = 0.8Î¼m. kuitira kuti iyo yepamusoro roughness kukosha kweRa = 0.2Î¼m, inogona kukwenenzverwa, nemucheka vhiri, plasma kukwesha kwendarira.
Jira vhiri kukwiza, kunoitwa nemachira kuita vhiri mhando inoshandiswa kupolisha. Iko kuomarara kwevhiri rekukwiza kunoonekwa nekureba kwetambo yemasuture, iyo diki daro remutsetse wesuture, iko kukwirira kuomarara kwevhiri repolishing. Polishing vhiri rinogona kugoverwa mune isina-kusonwa yakazara jira vhiri, mweya-wakatonhora jira vhiri uye yakasimbiswa mhando. Yasina kusonwa yakazara jira vhiri inowanzo kugadzirwa nemucheka wakapfava wedonje, inokodzera kupurinda yakaoma fomu workpiece, kana yeyaishoma workpiece yakanaka kupora. Mhepo-yakatonhorera jira vhiri ine 45º angle yekucheka nzira yekucheka, iri yakapetwa yakaita serin'i, iyo yepakati yakagadzirirwa diski disc, ine hunhu hwekufefetedza uye kupisa kupisa, inokodzera kupurinda hombe workpiece. Yekusona mhando inonyanya kugadzirwa nemachira ejena, isina-yakarukwa jira uye jira rakatsetseka, nezvimwewo, yekumonera tambo inogona kuve yakatenderedza denderedzwa mhando, yemhepo mhando uye yakatwasuka radiation radiation fomu, inokodzera kupukuta dzakasiyana-siyana raizi uye chimiro cheyakareruka workpiece. Makorari mhangura chiwanikwa, inowanzo shandiswa jira vhiri yakatenderedza kumhanya kwe22 ~ 30m / s, kune ichi chidzidzo cheiyo inoitisa mhete V-yakaita groove, iwo chaiwo matanho ekugadzirisa anofanirwa kuyedzwa.
3.3 Electrolyte plasma polishing
(1) electrolyte plasma polishing tsvagiridzo Plasma kupukuta ndiyo yekushandira uye kupukuta fluid mune yakasimbiswa yakadonhedzwa simbi ions yakashambadzirwa pamusoro peiyo workpiece, iyo workpiece bump nemhedzisiro yazvino kubvisa block, kuyerera kwazvino, iyo concave uye convex inogara ichichinja, pamusoro pechikamu ichi kunowedzeredzwa zvishoma nezvishoma. Iyo tekinoroji inogona kunyatso kugadzirisa iyo yepamusoro mhando yezvikamu.
(2) Kufuridzira zvinhu zveplasma kupora, izvo zvinokanganisa mhando yepashure yekukorobha ndeiyi: mhinduro tembiricha, nguva yekugadzirisa, kugadzirisa mhinduro, kudzika kwakadzika, mhinduro yekuyerera rate, nezvimwe. zvinoenderana nezvakakosha zvinokonzera zvinhu. Iyo yekumisikidza mhete V-groove saizi yekurwisa uku idiki, inoda kugadzira yekugadzirisa, uye kuitira kuti ive nechokwadi chekuenderana kwechikamu chese chikamu chekupora, inodawo kuti iwedzerwe yakagadziridzwa zvinoenderana nemidziyo, tenderera zvikamu, kuti madhiri ese eringi akapukutwa panzvimbo.
4 Sarudza iyo yekugadzirisa scheme
Iyi iri pamusoro chirongwa inonyanya kuongorora chishandiso, ayo ekugadzirisa parameter anogona kusarudzwa kuburikidza nemuchina chishandiso, maitiro acho ari nyore. Chirongwa chechipiri chejira jira kugadzira, chinogona kureva kushoma ruzivo, uye chikamu V-chakaumbwa paburi saizi idiki, hazvisi nyore kusungisa kushandiswa. Chirongwa chetatu cheplasma polishing tekinoroji chave chemberi tekinoroji, michina yekambani inogona kushandiswa zvizere, asi chirongwa chekuona kuenderana kwese kuridza mhete, kune mamwe matambudziko akaomarara ekugadzira. Uye kudiwa kwenhamba yakakura yemiyedzo pamatanho ekupora. Kuongorora kwakazara kwakagumisa kuti sarudzo yekutanga yakagamuchirwa.
The main purpose of this study is to make the surface roughness value Ra of copper alloy V-groove reach 0.2μm mirror effect. In the field of mirror surface processing of non-ferrous metals, diamond tools have better characteristics. During the implementation of the project, the more advanced mirror surface turning technology in the industry was investigated, researched and analyzed together with tool manufacturers, and customized suitable tools for processing tests. The machine test was carried out mainly in terms of tool feed, spindle speed, depth of cut and programmed machine method. Combined with the part material brass H62 and the mirror machine theory, the optimal parameters were found to achieve the mirror machine effect with the surface roughness value Ra=0.2μm of the part, and the batch production was verified according to the explored parameters.
4.1 Mirror machine tool research
According to the machine scheme, the mirror machine tool is investigated. The surface roughness of the part machine is influenced by the machine parameters, the main and sub-deflection angles of the turning tool, and the material and structure of the tool is also an important influencing factor.
The cutting edge of PCD (polycrystalline diamond) material consists of many microscopic crystals, and the tool with ultra-microscopic particles helps to reduce the surface roughness value of the part during the machine process.
The V-groove angle of this attacked part is 60º. In order to avoid machine interference and to meet the test of multiple machine methods, MVVNN symmetric toolholder was selected, and machine clamping tool was used considering the machine cost as well as the test convenience.
After research and analysis, Kyocera's ultra-fine grain PCD diamond inserts were selected for the machine test. The insert model is VBMT110301NE KPD001 with a tip angle of 35º and tip R=0.1mm, as shown in Figure 4.
a) Rutivi rwemberi rweKyocera yekuisa b) Rutivi rwekuseri kweKyocera yekuisa
Mufananidzo 4 Kyocera blade
Superfine PCD diamond ensures tip strength, wear resistance, chipping resistance (toughness), and sharpness for stable, long-life machine.
4.2 Machina Miedzo
According to the relevant machine parameters affecting the surface roughness, group tests are conducted, mainly from the programmed machine method, spindle speed, feed and depth of cut.
(1) Common machine methods for factory machine of V-groove type parts The common programming and machine methods for machine V-grooves in the workshop are the walking track type and the direct machine by forming tool. Forming knife direct machine has the characteristics of high processing efficiency, but the surface roughness of the machined parts is poor, and easy to damage the tool. Walking track machine has the characteristics of consistent surface of parts, less axial force on parts, and can effectively ensure the coaxiality of parts. Therefore, this test programming processing method uses the walking track type.
(2) group test 1 first consider the protection of the diamond tool in the initial determination of machine parameters test, first machine cylindrical surface to feel the appropriate machine parameters. Machining cylindrical surface, as shown in Figure 5, has reached the mirror effect. 2 according to the initial determination of machine parameters for the test machine of parts. In the test machine process, in the thickness of the larger cylindrical processing V-shaped groove, when the part thickness size reduced to 0.8mm, there is a knife machine trace problem, as shown in Figure 6. The preliminary analysis concluded that the vibration was caused by the thin wall thickness at the edge of the part. Therefore, the back draft and feed were gradually reduced and the speed was increased in the subsequent tests.3 After the improvements were made according to the problems that appeared above, the machined surface of the V-groove was greatly improved, but there were still spots, as shown in Figure 7.
Mufananidzo 5 Machining cylindrical pamusoro
Fig. 6 Tool machine marks
Mufananidzo 7 Nzvimbo dzepamusoro
After analyzing the machine path and parameters, and considering that the diamond tip is worn during rough machine, the carbide tool is selected for rough machine by re-calibrating the programming. Reserve 5mm machine allowance, then use diamond tool for finishing, choose spindle speed 1200r/min, feed f=0.03mm/r, for machine test. The surface of the V-groove of the part is smooth without spots, the tool marks are even, and the mirror effect is achieved (see Figure 8). The consistency of batch machine is good, and the surface roughness value reaches Ra=0.0638μm by the surface roughness instrument, as shown in Figure 9, which meets the requirements.
Mufananidzo 8 Mirror mhedzisiro
Mufananidzo 9 Roughness kuongorora ripoti
Kuburikidza nezvataurwa pamusoromultiple part machine tests
, the surface roughness of the part is greatly influenced by the tool and machine parameters. In the verification, the V-groove structure is continuously optimized, and the combination of tool and machine parameters is improved, and finally the surface of V-groove achieves the mirror effect. And the dimensional accuracy of the part is stable and the surface quality is consistent in batch machine, which achieves the target of the attack. By using super fine PCD diamond tools and MVVNN symmetric shanks, the mirror surface machine parameters were determined through experimental research, and the parameters and machine ideas can be extended to other parts that need to achieve the mirror surface effect to effectively improve the quality of the parts.