Hauv kev ua haujlwm ntawm CNC machining, nto roughness yog "tsis pom yardstick" rau kev ntsuas kev ua haujlwm thiab qhov zoo nkauj ntawm qhov chaw - los ntawm cov khoom siv tshuaj tua kab mob mus rau kev ntseeg siab ntawm aerospace seals, micron - qib kev ntxhib los mos sib txawv feem ntau txiav txim siab qhov ua tiav lossis tsis ua tiav ntawm cov khoom. Nrog rau kev kho dua tshiab ntawm precision manufacturing xav tau, yuav ua li cas sib npaug machining efficiency nrog cov ntsiab lus roughness xws li Ra (arthmetic txhais qhov siab) thiab Rz (siab kawg siab kawg nkaus - rau- hav qhov siab) tau dhau los ua ib qho kev sib tw tseem ceeb rau cov engineers kom kov yeej. Niaj hnub nimno CNC tshuab tau ntse tswj qhov saum npoo tiav hauv qab 0.4μm los ntawm cov cuab yeej ntse txoj kev optimization, dynamic txiav parameter hloov, thiab nano- theem polishing txheej txheem, thaum tshem tawm cov cuab yeej cuab tam thiab burrs hauv tsoos machining. Kab lus no yuav txheeb xyuas qhov cuam tshuam ntawm roughness ntawm precision qhov chaw los ntawm kev xaav ntawm kev siv tswv yim.
Nws txhais li cas hauv kev xyaum yog tias qhov roughness loj dua lossis me dua? Hauv lwm lo lus, nws cuam tshuam lub cev li cas? Piv txwv li, rau cov kabmob mating nto, xaiv Ra3.2 lossis Ra1.6 cuam tshuam dab tsi? Yog tias koj tau siv los xaiv tus nqi roughness raws li phau ntawv qhia lossis kev paub, thiab tsis tau xav txog cov lus nug no. Tom qab ntawd kuv vam tias tsab xov xwm no tuaj yeem qhib koj lub siab.
Peb yuav tsis xaiv qhov roughness casually. Kev xaiv ntawm qhov tshwj xeeb roughness yuav tsum tau ua kom tau raws li qee qhov kev ua haujlwm thiab txhim kho qee qhov kev ua tau zoo.
Rau ib feem, ntxiv rau qhov cuam tshuam rau qhov pom thiab kov ntawm ib feem, qhov loj ntawm qhov roughness feem ntau txhais tau tias qhov loj ntawm qhov kev ntxhov siab concentration. Los ntawm qhov kev pom ntawm microscopic (raws li qhia hauv daim duab dhau los), qhov loj dua qhov roughness, qhov siab qhov sib txawv ntawm cov pits ntau dua thiab ntau dua gullies. Nyob rau hauv cov cheeb tsam uas muaj siab tensile kev nyuaj siab loads, muaj kev ntxhov siab concentration ntawm lub gullies, uas kuj yog lub hauv paus chiv keeb ntawm cov kab nrib pleb. Yog li yog tias koj xav txhim kho qaug zog, koj yuav tsum xaiv qhov me me roughness.
Feem ntau, roughness yog siv rau kev sib piv ntawm ob qhov chaw. Ntawm no, roughness tuaj yeem cuam tshuam ntau yam, xws li kev sib txhuam coefficient, hnav, deformation, thermal conduction, to, adhesion, thiab lwm yam.
Qhov me me qhov roughness, qhov me me ntawm kev sib txhuam coefficient thiab kev sib txhuam tsis kam. Me me roughness yog yuav tsum tau ntawm ceev -rotating qhov chaw, xws li nruab nrab ntawm cov dov cov ntsiab lus thiab raceways ntawm bearings.
Nrog me me roughness, lub microscopic "me me peaks" yuav tsis siab heev los yog ntau heev. Thaum muaj kev vibration lossis siab siab ntawm ob qhov chaw, yuav tsis muaj kev hloov pauv hauv kev sib txuas nruj thiab micro- hloov pauv qhov sib txuam vim qhov flattening thiab compression deformation ntawm lub ncov, uas yuav txo tau qhov tshwm sim ntawm micro- txav txav.(MID yog ib tug ua CNC precision qhov chaw muab kev pab cuam, tsom rau muab cov neeg muas zaub nrog kev daws rau nto roughness.)
Qhov me me ntawm qhov roughness, qhov zoo ntawm qhov chaw haum ntawm ob qhov chaw, qhov zoo ntawm cov cua sov ua kom zoo, thiab qhov siab dua qhov yuav tsum tau roughness nyob rau hauv qee qhov chaw uas yuav tsum tau ua kom sov dissipation. Tsis tas li ntawd, me me roughness kuj yuav txo tau cov roj to.
Rau adhesion, ib qho ntxhib saum npoo tuaj yeem muab ntau qhov chaw rau cov nplaum, uas yuav pab txhim kho lub zog ntawm kev sib txuas, tab sis yog tias qhov chaw ntxhib dhau lawm, qhov chaw sib txuas tag nrho yuav raug txo, thiab huab cua yuav raug daig ntawm qhov sib koom ua ke, yog li ua rau lub zog sib txuas. Yog li xaiv nruab nrab.
Hauv cov ntsiab lus, kev xaiv ntawm roughness txawv ntawm daim ntawv thov mus rau daim ntawv thov. Nws yuav tsis muaj teeb meem hauv qee qhov kev siv thiab qhov chaw, tab sis nws yog qhov tseem ceeb hauv lub sijhawm thiab cov ntawv thov uas tau hais los saum toj no. Ua ntej xaiv qhov roughness, nws tsim nyog xav txog qhov kuv lub hom phiaj yog dab tsi.(Tau qhov twg los: iMechanics 机械)
