Txoj kev loj hlob ntawm riam yog ib qho tseem ceeb nyob rau hauv keeb kwm ntawm tib neeg kev vam meej. Thaum ntxov li 28th mus rau 20th centuries BC, tooj dag cones thiab tooj liab cones, xyaum, riam thiab lwm yam tooj liab riam tau tshwm sim nyob rau hauv Suav teb. Nyob rau lub sijhawm Warring States lig (thib peb caug xyoo BC), rab riam tooj liab tau tsim los ntawm kev paub txog kev siv tshuab carburizing. Drills thiab saws nyob rau lub sijhawm ntawd muaj qee qhov zoo sib xws nrog cov kev xyaum tiaj tus niaj hnub thiab cov saws.
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Keeb kwm luv luv ntawm cov cuab yeej txiav
Txoj kev loj hlob sai ntawm riam tuaj nyob rau hauv lub xyoo pua 18th nrog kev txhim kho ntawm cov tshuab xws li chav tshuab.
Nyob rau hauv 1783, René ntawm Fabkis thawj tsim milling cutters. Xyoo 1923, Lub Tebchaws Yelemees Schrotter tau tsim cov cemented carbide. Thaum siv cov cemented carbide, qhov ua tau zoo yog ntau tshaj li ob zaug ntawm cov hlau nrawm, thiab qhov zoo ntawm qhov chaw thiab qhov tseeb ntawm cov khoom ua tiav los ntawm kev txiav kuj zoo heev.
Vim yog tus nqi siab ntawm high-speed steel thiab cemented carbide, xyoo 1938, German Degusa Company tau txais patent ntawm cov riam ceramic. Xyoo 1972, General Electric Company ntawm Tebchaws Meskas tau tsim cov pob zeb diamond polycrystalline thiab polycrystalline cubic boron nitride hniav. Cov khoom siv tsis yog xim hlau no tso cai rau cov cuab yeej txiav ntawm qhov nrawm dua.
Xyoo 1969, Swedish Sandvik Steel Works tau txais daim ntawv pov thawj rau kev tsim cov titanium carbide-coated carbide inserts los ntawm cov tshuaj vapor deposition. Xyoo 1972, Bangsha thiab Lagolan hauv Tebchaws Meskas tau tsim cov txheej txheem ntawm lub cev vapor deposition los txheej txheej tawv ntawm titanium carbide lossis titanium nitride rau saum npoo ntawm cemented carbide lossis cov cuab yeej siv hlau ceev. Cov txheej txheem txheej txheej ua ke ua ke lub zog siab thiab tawv ntawm cov khoom siv nrog lub siab tawv thiab hnav tsis kam ntawm txheej txheej, kom cov khoom sib xyaw muaj kev ua tau zoo dua.
Vim yog qhov kub thiab txias, kev kub siab, kev kub ceev, thiab qhov chaw ua haujlwm hauv cov kua dej tawm, ntau thiab ntau cov ntaub ntawv nyuaj-rau-tshuab siv, thiab automation theem ntawm kev txiav thiab cov kev cai rau kev ua kom raug tau nce siab dua. . Thaum xaiv lub kaum sab xis ntawm lub cuab yeej, nws yog ib qho tsim nyog yuav tau xav txog qhov cuam tshuam ntawm ntau yam, xws li cov khoom siv ua haujlwm, cov khoom siv, cov khoom siv (ntxhiab thiab tiav machining), thiab lwm yam, uas yuav tsum tau xaiv kom tsim nyog raws li qhov xwm txheej tshwj xeeb.
Cov cuab yeej siv: cov hlau ceev ceev, cemented carbide (xws li cermet), ceramics, CBN (cubic boron nitride), PCD (polycrystalline pob zeb diamond), vim lawv hardness yog ib qho nyuaj tshaj ib qho, feem ntau hais lus, txiav ceev kuj yog ib qho. siab dua lwm tus.
Cov khoom siv ntsuas kev ua haujlwm
High-speed steel: Nws tuaj yeem muab faib ua cov hlau zoo tib yam high-speed steel thiab high-speed steel.
Ordinary high-speed steel, xws li W18Cr4V, yog siv dav hauv kev tsim ntau yam riam phom. Nws qhov ceev txiav feem ntau tsis siab dhau, thiab nws yog 40-60m / min thaum txiav cov khoom siv hlau.
Cov hlau ua haujlwm siab ceev, xws li W12Cr4V4Mo, yog smelted los ntawm kev ntxiv qee cov ntsiab lus carbon, vanadium cov ntsiab lus, cobalt, txhuas thiab lwm yam khoom rau cov hlau zoo tib yam. Nws cov kav ntev yog 1.5-3 npaug ntawm cov hlau zoo tib yam.
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Cemented carbide: Raws li GB2075-87 (xa mus rau 190 tus qauv), nws tuaj yeem muab faib ua peb pawg: P, M, thiab K. P-hom cemented carbide yog siv los ua cov hlau ferrous nrog cov chips ntev, thiab xiav yog siv los ua cim; M-hom feem ntau yog siv. Nws yog siv los ua ferrous hlau thiab non-ferrous hlau, thiab nws yog cim nrog daj, kuj hu ua general-purpose hard alloy. K hom feem ntau yog siv rau kev ua cov hlau ferrous, cov hlau tsis muaj hlau thiab cov khoom tsis yog xim hlau nrog cov chips luv, thiab nws yog cim nrog liab.
Cov lej Arabic tom qab P, M, thiab K qhia nws qhov kev ua tau zoo thiab kev ua haujlwm thauj khoom lossis kev ua haujlwm. Tus naj npawb tsawg dua, qhov hardness ntau dua thiab qhov hnyav dua qhov toughness.
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Ceramics: Cov ntaub ntawv ceramic muaj qhov hnav tsis zoo thiab tuaj yeem ua cov ntaub ntawv hardness uas nyuaj los yog ua tsis tau raws li cov cuab yeej tsoos. Tsis tas li ntawd, cov cuab yeej txiav ceramic tuaj yeem zam lub zog siv ntawm kev ua haujlwm annealing, thiab yog li tuaj yeem ua rau lub zog ntawm cov khoom ua haujlwm thiab ua kom lub neej ntev ntawm cov khoom siv tshuab.
Kev sib txhuam ntawm cov hniav ceramic thiab cov hlau yog me me thaum txiav, txiav tsis yooj yim rau lo rau ntawm cov hniav, thiab nws tsis yooj yim los tsim cov ntug tsim, thiab nws tuaj yeem ua kev txiav ceev. Yog li ntawd, nyob rau hauv tib yam kev mob, lub nto roughness ntawm lub workpiece yog kuj tsawg. Cov cuab yeej siv tau ntev yog ob peb zaug lossis ntau zaus ntau dua li cov cuab yeej ib txwm siv, uas txo cov cuab yeej hloov pauv thaum ua haujlwm.
Kub kub kuj, zoo liab hardness. Nws tuaj yeem txiav tsis tu ncua ntawm 1200 degree, yog li kev txiav ceev ntawm ceramic inserts tuaj yeem siab dua li ntawm cov cemented carbide. Nws tuaj yeem ua kev txiav ceev lossis paub tias "hloov kev sib tsoo nrog tig thiab milling". Qhov kev ua tau zoo ntawm kev txiav yog 3-10 npaug ntau dua li cov cuab yeej txiav tsoos, thiab cov txiaj ntsig ntawm kev txuag txiv neej-teev, hluav taws xob, thiab cov cuab yeej siv tshuab los ntawm 30 feem pua -70 feem pua lossis siab dua yog ua tiav.
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CBN: Qhov no yog qhov thib ob siab tshaj plaws hardness khoom tam sim no paub. Lub hardness ntawm CBN composite ntawv feem ntau yog HV3000 ~ 5000, uas muaj thermal stability thiab siab kub hardness, thiab muaj siab oxidation kuj. Ntawm 1000 degree C Oxidation tsis tshwm sim, thiab tsis muaj tshuaj lom neeg tshwm sim nrog cov khoom siv hlau ntawm 1200-1300 degree C. Nws muaj thermal conductivity zoo thiab tsis tshua muaj kev sib txhuam coefficient.
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Polycrystalline pob zeb diamond PCD: Pob zeb diamond riam muaj cov yam ntxwv ntawm siab hardness, siab compressive zog, zoo thermal conductivity thiab hnav tsis kam, thiab tuaj yeem tau txais kev ua haujlwm siab thiab kev ua haujlwm siab hauv kev txiav ceev. Txij li cov qauv ntawm PCD yog cov pob zeb zoo nkauj sintered lub cev nrog cov kev taw qhia sib txawv, nws cov tawv tawv thiab hnav tsis kam tseem qis dua li cov pob zeb diamond ib leeg txawm tias qhov sib ntxiv ntawm cov ntawv khi. Lub affinity nrog non-ferrous hlau thiab non-metallic cov ntaub ntawv yog heev me me, thiab chips tsis yooj yim rau lo rau lub ntsis ntawm lub cuab tam los tsim-up ntug thaum ua.
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Cov ntsiab lus
Qhov ntau ntawm kev siv ntawm txhua yam khoom
High-speed steel: feem ntau yog siv nyob rau hauv lub sij hawm uas yuav tsum tau siab toughness xws li cov cuab yeej thiab complex duab;
Cemented carbide: qhov dav tshaj plaws ntawm kev siv, muaj peev xwm ua tau;
Ceramics: Feem ntau yog siv nyob rau hauv ntxhib machining thiab high-speed machining ntawm qhov nyuaj tig thiab cam khwb cia hlau qhov chaw;
CBN: Feem ntau yog siv rau hauv qhov nyuaj tig thiab ua haujlwm siab ceev ntawm cov hlau cam khwb cia (feem ntau hais lus, nws muaj txiaj ntsig ntau dua li cov ceramics ntawm kev hnav tsis kam, cuam tshuam toughness thiab tawg tsis kam);
PCD: Feem ntau yog siv rau kev ua haujlwm siab ntawm cov hlau tsis muaj hlau thiab cov khoom tsis yog hlau.
