Dab tsi yog qhov cuam tshuam ntawm Kev Rov Ua Dua Ultrasonic ntawm Qhov Nto Hardness ntawm PFA Rhaub Tshaj 1 Xyoo?

Cavitation npuas yog tsim los ntawm kev tu ultrasonic ntawm 20 kHz, uas yog ib txwm muaj rau cov tso tsheb hlau luam. Cov npuas no tawg ze rau ntawm PFA nto. Lub tshuab cua sov PFA qhov tawv tawv nce los ntawm 10–20 Shore D units (los ntawm 65–68 txog 75–85) tom qab ib xyoos ntawm txhua hnub 15-feeb cycles (tag nrho ntawm 91 teev). Kev ua haujlwm txias hauv cheeb tsam, microcracking, thiab hla- txuas los ntawm kev cuam tshuam rov ua dua cavitation yog qhov ua rau qhov tawv tawv no. Thaum cov txheej saum npoo tawg, elongation txo los ntawm 300% mus rau 50-100%, ua rau saum npoo nkig. Txawm li cas los xij, qhov hardening yog txwv rau sab nrauv 50-150 µm ntawm PFA phab ntsa uas yog 2 hli tuab. Cov khoom yog tseem ductile nyob rau hauv tej. Yog tias qhov chaw tsis tsim los ntawm kev tawg, lub tshuab rhaub tuaj yeem tiv taus txhua hnub 15-feeb ultrasonic tu rau ib xyoos tsis ua haujlwm. Txawm li cas los xij, kev caij tsheb kauj vab cua sov tuaj yeem ua rau qhov chaw embritted tawg tom qab ob mus rau peb xyoos. Siv daim thaiv titanium los yog txwv tsis pub raug ultrasonic tsawg dua tsib feeb hauv ib hnub rau cov kev pabcuam tseem ceeb.

Cavitation Hardening txheej txheem
Cavitation npuas vau ntawm 20 kHz rau microseconds ntawm qhov kub ntawm 2,000 thiab 5,000℃thiab siab ntawm 100 thiab 1,000 bar. PFA nto yog plastically deformed los ntawm shockwave, ua rau micro-voids thiab dislocations. Hardness yog nce los ntawm kev taw qhia thiab hla -txuas ntawm polymer chains ze rau saum npoo. Qhov saum npoo ua ntej ua smoother (peaks raug tshem tawm), tab sis raws li micro- qhov tsim, nws ua rougher. Txawm hais tias muaj zog dua, cov txheej txheem yog piv rau kev txhaj tshuaj peening. PFA ua nkig, sib piv rau cov hlau uas muaj kev ntxhov siab.

Qhov tob hardening yog txiav txim los ntawm d_hard=0.5 × (frequency)^(-0.5) × (power)^0.3. Tom qab 100 teev, d_hard ≈ 80–150 µm ntawm 20 kHz thiab 100 W / L. Qhov no tsuas yog 5-7% ntawm lub thickness rau 2 hli phab ntsa, yog li ntawd lub rhaub yog tseem muaj zog structurally.

Surface Hardness vs Ultrasonic Exposure (25℃dej, 20 kHz, 100 W / L)
Tag Nrho Cov Hluav Taws Xob (teev) Lub voj voog Txhua hnub (15 feeb txhua hnub) Cov Txheej Txheem Nthuav Ntxiv ntawm Kev tawg (nto txheej) Sib npaug Hnub Nto Hardness (Shore D) Hardness nce
0 0 0 66 0 ci iab, du 300%
40 hnub 68–{2}} Me ntsis matte 250–280% 10–15 feeb txhua hnub
Matte, nplua pits 200–250% 50 15 min/hnub 200 hnub 73–78 25 15 min/hnub 100 hnub 70–74 +4–8+7–12 Dull, pom pits 150–200% 75–15 min/hnub 300 microcks 7,6 hnub 100–150% 100 ~ 15 min/hnub 400 hnub 78–{25}}–19 Cracked nto 50–100% 150 ~ 15 min/hnub 600 hnub 80–88 +14–22 Cracked, hmoov<50%
25 (50 kHz) 15 feeb ib hnub 100 hnub 85–90 + 19–24 Pitting hnyav<30% (worse at higher frequencies)
Cavitation muaj teeb meem ntau dua ntawm 50 kHz (saib Tshooj #13). PFA rhaub yuav tsum tsis txhob siv nyob rau hauv ultrasonic ntxuav nrog zaus siab tshaj 40 kHz.

Kev cuam tshuam rau kev ua haujlwm ntawm cov cua sov
Qhov saum npoo hardening tsis ua rau tsis ua hauj lwm tam sim ntawd, txawm tias tom qab ib xyoos (91 teev ntawm qhov raug). Cov cua sov tseem ua haujlwm. Tab sis:

Kev nkag mus nce ntxiv: Tsis muaj kev tiv thaiv tshuaj lom neeg permeation vim lub microcracked nto txheej. Tom qab ib xyoos ntawm kev tu ultrasonic, qhov nkag mus rau 30% HCl ntawm 80℃yog ob mus rau peb zaug siab dua li ntawm lub tshuab hluav taws xob tsis pom.

Ua kom cov nplai adhesion: nplai thiab biofilms raug daig los ntawm qhov tsis sib xws, yuav tsum tau ntxuav ntau zaus.

Thermal shock resistance poob qis: Kev txias nrawm ua rau lub ntsej muag nkig kom tawg yooj yim dua.

Ib xyoo ntawm ib hnub 15-feeb cycles yog tsim nyog rau lub rhaub nyob rau hauv ib tug huv si, tsis muaj tshuaj lom neeg (ultrasonic tu ntawm chav kuaj iav). Kev ntxhov siab tawg yog nrawm rau lub rhaub hauv cov tshuaj lom neeg hnyav thaum ultrasonic hardening thiab tshuaj tua kab mob sib xyaw ua ke.

Ultrasonic Service Mitigation
Yog tias PFA rhaub yuav tsum tau ntxuav ultrasonically:

Txwv tsis pub ntau tshaj tsib feeb txhua hnub. Hardness tau nce los ntawm 4-8 units tom qab ib xyoos, uas yog tsim nyog.

Siv ib daim ntaub thaiv npog: Cavitation zog yog absorbed los ntawm perforated titanium los yog stainless hlau shield muab tso rau peb mus rau tsib millimeters deb ntawm PFA. PFA tsis hnav cov ntaub thaiv npog.

Txo lub zog ultrasonic los ntawm 100 W / L mus rau 30 W / L kom tau txais lub zog qis dua . 50-70% tsawg hardness yog ntxiv ntawm 30 W / L.

Siv cov PFA tuab dua vim tias phab ntsa 3 hli muaj cov khoom siv ntau dua thiab ua rau cov kab nrib pleb ntawm cov nplaim tawg mus rau cov tub ntxhais hlau.

Piv txwv hauv Teb
PFA lub tshuab rhaub cua sov tau ntxuav txhua txhua hnub rau 30 feeb siv 20 kHz ultrasonic nqus tsev vacuum nyob rau hauv ib lub semiconductor lab. Cov cua kub saum npoo tau ua hmoov thiab hnyav tom qab kaum yim hli. Ib lub tshuab cua sov ua tsis tiav vim qhov tawg ntawm cov kua kab. Lub chaw soj nstuam tau teeb tsa lub titanium shield (1 hli tuab, 40% qhib cheeb tsam) nyob rau hauv qhov chaw ntawm cov cua sov. Tom qab 24 lub hlis, tsis muaj qhov tawv tawv ntawm cov cua sov tshiab. Txhua 12 lub hlis, cov ntaub thaiv npog tau hloov pauv ntawm tus nqi ntawm $ 100.tus nqi $ 100). $ 2,000 hauv qhov cub hloov tau zam vim tias mus txog $ 100 txhua xyoo.

Hauv kev xaus, tom qab ib xyoos ntawm kev tu txhua hnub 15-feeb, nws hardens los ntawm 10-20 Shore D.
PFA heater deg hardness yog nce los ntawm 10-20 Shore D units, los ntawm 65-68 mus rau 75-85, tom qab rov ua ultrasonic tu ntawm 20 kHz (15 feeb ib hnub) rau ib xyoos. Cov PFA feem ntau tseem ua tau zoo, tab sis cov tawv tawv tawv dhau los ua nkig thiab tuaj yeem tsim microcracks. Hauv cov tshuaj me me, lub tshuab cua sov tuaj yeem kav ib xyoos yam tsis muaj kev tawg, txawm hais tias nplai adhesion thiab permeation zuj zus. Txo lub zog ultrasonic, ntxiv titanium ntaub thaiv npog, lossis txwv tsis pub dhau tsib feeb txhua hnub rau lub neej ntev dua. Kev puas tsuaj loj ntawm 50 kHz; yeej tsis siv. Ntxiv nrog rau kev tu, ultrasonic tu ua rau muaj kev puas tsuaj. Txwv koj lub rhaub dej lub sijhawm da dej lossis tiv thaiv nws. Qhov saum npoo tuaj yeem ua tsis tiav, tawv, thiab tawg. Khaws kom zoo los yog hloov nws ntau zaus. Koj qhov kev txiav txim siab.