Thaum Tshav Kub Ferric Chloride Etchant (42℃Bé) ntawm 50 degree, Vim li cas Titanium Qib 7 tuaj yeem txo qis General Corrosion Rate (0.01 hli / xyoo) dua qib 2 (0.2 hli / xyoo)?

Ferric chloride (FeCl₃) etchant ntawm 42℃Bé (ib puag ncig 38-40% FeCl₃ los ntawm qhov hnyav) yog qhov nruab nrab rau etching tooj liab- clad Circuit Court boards thiab rau cov tshuaj milling ntawm hlau. Cov tshuaj yog oxidizing heev, hnyav acidic (pH 0.5-1.0) thiab suav nrog txog 200-250 g / L chloride ions. Titanium yog siv dav rau cov cua sov hauv FeCl 3 etching kab vim nws zoo heev tsis kam mus rau chloride pitting nyob rau hauv oxidizing tej yam kev mob. Tab sis muaj qhov sib txawv tseem ceeb ntawm kev lag luam ntshiab Qib 2 thiab palladium-stabilized Qib 7 titanium. Nyob rau hauv lub sij hawm ntev kev pab cuam ntawm 50℃qhov dav corrosion tus nqi ntawm Qib 7 yog 0.01-0.03 hli ib xyoo thaum Qib 2 corrodes ntawm 0.15-0.25 hli ib xyoo, ib qho tseem ceeb ntawm 10 qhov sib txawv. Daim ntawv no piav qhia txog cov txheej txheem electrochemical ntawm qhov kev sib txawv ntawm qhov kev ua tau zoo no thiab txhais tau tias thaum tus nqi ntxiv ntawm Qib 7 yog qhov tseeb los ntawm nws qhov txo qis corrosion.

Ferric chloride ua oxidizing tus neeg sawv cev
Ferric chloride yog ib qho muaj zog oxidant vim Fe 3+ / Fe 2+ redox khub nrog ib tug raug txo qhov peev xwm ntawm +0.77 V vs. SHE. Lub peev xwm ua tau zoo yog +0.6 rau +0.8 V vs SCE hauv kev daws teeb meem ntawm 50℃. Qhov no yuav tsum yog ib puag ncig oxidising heev thiab xav kom tag nrho passivate titanium. Qib 2 thiab Qib 7 yog passive. Lub passive txheej ntawm titanium tsis zoo li qub, tab sis tsis tu ncua dissolving thiab hloov kho. Tus nqi ntawm dissolution yog tswj los ntawm chemistry ntawm titanium- kev daws teeb meem interface, tshwj xeeb tshaj yog cov concentration ntawm complexing anions (chloride) thiab muaj cov noble hlau catalysts.

FeCl3 Qib 2 Corrosion Mechanism
The passive TiO₂ txheej ntawm Qib 2 titanium hauv FeCl₃ kua yog maj mam yaj TiO₂ + 4Cl⁻ + 4H⁺ → TiCl₄ + 2H₂O. TiCl₄ yog hydrolyzed rau hom soluble. Ib txhij nrog kev sib cais, zaj duab xis yog rov- tsim los ntawm kev sib cuam tshuam ntawm titanium nrog dej lossis oxygen. Lub xeev khov kho tus nqi ntawm 50℃yog 0.15-0.25 hli hauv ib xyoos, qhov tshwm sim ntawm qhov sib txawv ntawm kev sib cais thiab cov nqi rov ua dua. Tus nqi yog kub nyob ntawm: ntawm 40℃Qib 2 corrodes ntawm 0.05-0.10 hli / xyoo, ntawm 60℃tus nqi dhia mus rau 0.4-0.6 hli / xyoo.

Corrosion yog dav (universal) thiab tsis pitting. Qib 2 lub raj phab ntsa yuav nyias maj mam thiab sib npaug thaum lub hli ua haujlwm. Lub 1.65 hli tuab raj siv nyob rau ntawm 50℃yuav poob li ntawm 0.2 hli ib xyoo, ua rau lub neej kev pab cuam ntawm 5-8 xyoo mus txog rau qhov tsawg kawg nkaus permissible phab ntsa thickness yog mus txog (feem ntau 1.0 hli rau mechanical kev ncaj ncees).

Qib 7 Kev Kho Mob Catholic
Titanium in grade 7 contains between 0.12 to 0.25% palladium, which is dispersed as fine islands throughout the titanium matrix. Titanium has a good cathodic site and is less noble than Palladium. The main cathodic reaction on Pd in FeCl3 solution is . Fe3+ + e- ->Fe2+ Cov tshuaj tiv thaiv no yog pib ntawm qhov qis dua ntawm palladium dua li ntawm titanium, qhia tias feem ntau ntawm cov cathodic tam sim no tshwm sim ntawm qhov chaw palladium. Lub titanium matrix polarises mus rau lub peev xwm loj dua, feem ntau +0.3 rau +0.5 V muaj txiaj ntsig ntau dua qib 2 nyob rau hauv tib lub sijhawm.

Raws li qhov muaj peev xwm muaj txiaj ntsig zoo dua TiO₂ zaj duab xis dissolving tus nqi poob exponentially. Kev ntsuam xyuas hluav taws xob qhia tau hais tias qhov passive tam sim no ceev ntawm Qib 7 hauv FeCl3 ntawm 50℃yog 0.5-1.0 µA / cm2, uas yog sib npaug rau qhov corrosion ntawm 0.005-0.010 hli ib xyoos twg. Lub palladium tsis tas yuav npog tag nrho saum npoo, vim tias 0.5-1.0% palladium Islands tuaj ntawm qhov chaw txaus los xyuas kom muaj kev tiv thaiv cathodic.

Kev sib piv ntawm Ntev -Lub Sij Hawm Ua Haujlwm
Field validation yog muab los ntawm teb cov ntaub ntawv los ntawm PCB etching chaw siv 42℃Bé FeCl 3 ntawm 50 degree. Qib 2 titanium heaters (1.65 hli phab ntsa) feem ntau muaj phab ntsa thinning lub neej ntawm 5-7 xyoo thiab yuav tsum tau hloov. Qib 7 cua sov (1.65 hli phab ntsa) tau ua haujlwm rau 15+ xyoo nrog ntsuas phab ntsa thickness poob qis dua 0.2 hli tag nrho. Qib 7 raug nqi ntau dua (kwv yees li 30-40% ntau dua li Qib 2), tab sis nws them rau nws tus kheej nrog lub neej ua haujlwm ntev thiab qis dua.

Khoom siv dav dav corrosion tus nqi @ 50℃Lub Sijhawm mus rau 50% phab ntsa poob (1.65 hli txog 0.8 hli) Daim ntawv thov txheeb ze tus nqi cuam tshuam tus nqi-Cov txiaj ntsig zoo
Qib 2 titanium 0.15-0.25 hli/yr 3-5 xyoo 1.0x Tsawg-ntim, sib tshuam etching
Qib 7 titanium 0.01-0.03 mm / xyoo 15-25 xyoo 1.3-1.4x High-volume, nruam txheej txheem
Hastelloy C-276 0.02-0.05 mm/xyoo 10-15 xyoo 2.5-3.0x Tsuas yog daim ntawv thov tshwj xeeb
FeCl₃ Heat Source Selection Application Matrix
Etching Ua Haujlwm Kub Da Dej Turnover RateTitanium Qib RecommendedHeater Life Expected (1.65 mm phab ntsa)
Tsawg- ntim PCB prototyping 50℃Intermittent, da dej hloov txhua hli Qib Qib 2 5-7 xyoo
siab ntim PCB fabrication 50℃Nruam, da dej regenerated Qib 7 12-15 xyoo
Tshuaj etching (tuab hlau) 55-60℃High siv, nruam Qib 7 8-10 xyoo
Regenerated FeCl₃ (tsawg Fe²⁺) 50℃Nruam Qib 7 15+ xyoo
Siv FeCl₃ (siab Fe²⁺, tsawg oxidizing) 50℃Batch pov tseg Qib 2 4-6 xyoo
Kev hloov kho cathodic los ntawm palladium hauv titanium qib 7 ua rau tag nrho cov nqi corrosion ntawm ib tug nees nkaum ntawm qib 2 hauv ferric chloride etchant ntawm 42 degrees B thiab 50 degrees C. Cov chaw palladium hloov kho cov titanium nto muaj peev xwm ua rau muaj txiaj ntsig zoo dua, ua rau txo qis hauv cov yeeb yaj kiab tsis zoo. Rau kev ua haujlwm siab ntxiv -kev tsim khoom etching qhov chaw tso cua sov thiab lub neej ua haujlwm ntev yog qhov tseem ceeb, qhov pib nqi siab dua ntawm Qib 7 yog lav. Qib 2 tseem yog qhov kev xaiv zoo rau kev siv tsis sib xws lossis siv ntim tsawg qhov twg 5-7 xyoo lub tshuab cua sov siv tau. Thaum qhia meej nug txog qhov tseeb corrosion tus nqi sau tseg hauv cov tshuaj FeCl3 tshwj xeeb. Cov kab mob sib kis (tooj liab, npib tsib xee) tuaj yeem cuam tshuam kev ua yeeb yam.