Qhov zoo ntawm Graphite ua cov khoom siv hluav taws xob (EDM vs Copper)

Ntsiab Cai

• Graphite feem ntau yog 2-5 zaug sai dua tooj liab hauv machining thiab 2-3 zaug sai dua hauv EDM, uas ua rau lub sij hawm luv electrode.
• Graphite resists thermal deformation: nws sublimes ntawm li 3650℃thiab nws coefficient ntawm thermal expansion yog qis dua tooj liab.
• Graphite ntau dua li tooj liab (kwv yees li 1/5 ntawm qhov ntom), uas txo lub nra ntawm cov cuab yeej siv tshuab rau cov electrodes loj.
• Thaum lub sij hawm EDM, carbon los ntawm lub txim roj deposits ntawm lub graphite nto thiab ib feem compensates electrode hnav.

1. Kev ua haujlwm ceev ceev

Graphite feem ntau yog 2-5 zaug sai dua tooj liab hauv machining thiab 2-3 zaug sai dua hauv hluav taws xob tawm tshuab (EDM), uas yog ib qho ntawm cov laj thawj tseem ceeb uas nws ua rau EDM electrode xyaum niaj hnub - feem ntau hais cov duab qhia tias ntau dua 90% ntawm EDM electrodes hauv Europe yog ua los ntawm graphite. Faster machining shortens electrode ntau lawm lub sij hawm thiab txo tus nqi rau complex geometry.

2. Resistance rau Deformation

Nyias-walled ribbed electrodes tau txais txiaj ntsig zoo tshaj plaws los ntawm graphite qhov ruaj khov. Copper muaj qhov muag muag ntawm li 1000℃thiab nws yooj yim rau thermal deformation thaum lub tshuab hnyav lossis tawm, thaum graphite sublimes ntawm txog 3650 degree. Lub coefficient ntawm thermal expansion ntawm graphite yog li 2-5 x 10-6 / degree, piv nrog li 17 x 10-6 /℃rau tooj liab - kwv yees li 1/4 txog 1/8 ntawm tooj liab, nyob ntawm qib graphite - yog li cov electrodes loj kom lawv cov duab zoo dua.

3. Lub teeb yuag

Graphite muaj qhov ntom ntawm 1.7-2.2 g / cm3, kwv yees li ib feem tsib ntawm tooj liab (8.9 g / cm3). Thaum cov khoom siv hluav taws xob loj siv hauv EDM, qhov hnyav qis yuav txo tau lub nra ntawm lub tshuab cuab yeej thiab ua rau kev tuav tau yooj yim dua, uas haum rau kev siv pwm loj.

4. Tshem tawm tus cwj pwm thiab Carbon Deposition

Graphite electrodes qhia me me paug noj hauv ntau txoj cai. Thaum lub sij hawm tso tawm, cov pa roj carbon atoms nyob rau hauv lub txim roj decompose nyob rau hauv high kub thiab muaj peev xwm tso ib tug tiv thaiv zaj duab xis ntawm graphite electrode nto, ib feem compensating rau electrode poob. Cov nyhuv yog nyob ntawm cov txheej txheem tsis, hom roj thiab qib graphite, yog li nws yuav tsum tau kho raws li qhov muaj txiaj ntsig zoo dua li qhov lav.

5. Kev lag luam-Offs los xav txog

Graphite kuj muaj qhov tsis zoo: nws yog nkig ntau dua tooj liab, yog li cov npoo tuaj yeem nti thaum tuav thiab ua haujlwm, thiab graphite plua plav yog conductive, yuav tsum tau tshem tawm plua plav thiab qhov cua. Copper tseem nyiam rau qee qhov zoo - tiav, cov electrodes me me uas nws cov ductility thiab cov ces kaum qis hnav hauv lub teeb tseem ceeb. Xaiv cov khoom siv los ntawm electrode geometry, txoj kev machining thiab qhov yuav tsum tau ua tiav.

Cov lus nug nquag

Q1. graphite sai npaum li cas tshaj tooj liab hauv EDM?
Feem ntau 2-3 zaug nrawm dua hauv EDM thiab 2-5 zaug nrawm dua hauv kev ua haujlwm, nyob ntawm qib thiab geometry.

Q2. Vim li cas graphite tiv thaiv thermal deformation?
Nws sublimes ntawm li 3650℃thiab muaj ib tug tsawg coefficient ntawm thermal expansion, kwv yees li 1/4-1/8 ntawm tooj liab.

Q3. Puas yog graphite ib txwm zoo dua tooj liab rau electrodes?
Tsis tas li - tooj liab tseem tuaj yeem haum zoo - ua kom tiav cov electrodes me me; graphite dominates ceev thiab loj - electrode ua hauj lwm.

Q4. Puas yog graphite plua plav xav tau kev tuav tshwj xeeb?
Yog - graphite hmoov av yog conductive; siv cov plua plav tshem tawm thiab qhov cua thaum ua haujlwm.