Rau PFA (Perfluoroalkoxy) Coated Titanium rhaub Siv nyob rau hauv 10% Hydrofluoric Acid Solution ntawm 60 degree, Lub Txheej Thickness (0.3 hli vs . 0.8 hli) Hloov Lub Sijhawm Diffusion li cas-Txoj Kev Tawm Tsam ntawm Titanium Substrate Tom Qab Pinhole Tsim?

PFA-coated titanium rhaub nyob rau hauv 10% hydrofluoric acid ntawm 60℃nyob ntawm cov txheej rau kev tiv thaiv ntawm substrate. Yog hais tias tus pinhole tsim, HF yuav diffuse tom qab hauv qab txheej thiab tawm tsam cov titanium. Tsim ib lub pinhole yuav muab 500 - 1,000 teev tiv thaiv nrog 0.3 hli txheej thiab 2,000 - 4,000 teev nrog 0.8 hli txheej. Qhov nce nyob rau hauv lateral diffusion txoj kev ntev vim lub thicker txheej ncua lub perforation ntawm lub substrate. Mechanism of Undercoating Corrosion in HF Ib tus pinhole tso cai rau HF mus txog titanium substrate. Cov titanium yog corroding: Ti + 6HF=TiF 6 2- + 3H 2 + 2H +. Cov khoom corrosion yog soluble thiab tsis kaw lub pinhole. HF tsiv mus rau sab hauv qab ntawm PFA npog, uas yog undermined. Lub sij hawm xav tau los txo qhov kev ncua deb L yog proportional rau L2. Quantitative Undercutting Sijhawm raws li Kev Ua Haujlwm ntawm Txheej Txheej Thickness Txheej Thickness (mm) Undercut Rate (mm / 100 h) Lub Sijhawm rau 1mm 'Undercut (hrs) Lub Sijhawm rau perforation ntawm substrate (teev) 0.2 0.5-1.0 100-200 150-300 0.3 0.3-0.6 150-300 500-1,000 0.5 0.1-0.3 300-1,000 1,000-2,500 0.8 0.05-0.15 600-2,000 2,000-4,000 1.0 0.03-0.10 1,000-3,000 3,000-6,000 Txheej Thickness Selection Guide for HF Service Desired (Kev Pabcuam Thickness) Cov Kev Pab Cuam Tshuam Tsawg Tawm tswv yim 500 0.3 Txwv 1,000 Passable 0.5 2, 000 0.8 Sì 4,000 1.0 Yog Qhia Txog Specification Qhia ib txheej thickness ntawm 0.8-1.0 hli rau PFA-coated titanium rhaub nyob rau hauv 10% HF ntawm 60℃kom ua kom muaj kev pab cuam lub neej ntau tshaj ib zaug. Tus engineer tswj lub thickness ntawm txheej kom nthuav dav lub qhov rais ua haujlwm nyab xeeb.