Nws yog ib yam uas tsis muaj nqi hlau porcelain hniav. Porcelain fused to hlau (PFM) yog cov txheej txheem siab heev rau kev kho hniav. Nws muaj qhov zoo ntawm kev zoo nkauj, naturalness, firmness thiab hnav tsis kam. Nws yog ib qho khoom nyiam rau ntau tus neeg mob uas muaj kab mob hniav. Yog li dab tsi yog qhov muaj pes tsawg leeg ntawm cobalt chrome plooj (porcelain hniav)? Feem ntau, chromium tsis tsawg dua 25 feem pua, molybdenum tsis tsawg dua 4 feem pua, thiab tag nrho cov cobalt, npib tsib xee thiab chromium tsis tsawg dua 85 feem pua. Muaj ntau cov kev xav txog qhov zoo ntawm cobalt chromium alloy porcelain hniav. Qee tus neeg xav tias nickel chromium alloy porcelain hniav yog dav siv vim lawv cov nqi qis. Ntau tshaj 50 feem pua ntawm cov neeg mob uas muaj cov hniav plooj (porcelain) xaiv cov hniav porcelain no. Biological fusion yog qhov zoo, zoo nkauj, pheej yig thiab ruaj khov. Txawm li cas los xij, qee tus neeg tau lees paub tias hom plooj (porcelain) fused rau cov hniav hlau no muaj cov khoom siv tsis zoo, uas yooj yim ua rau muaj kev tsis haum rau qee tus neeg thiab ua rau mob ntawm daim tawv nqaij thiab mucosa. Kev siv cov porcelain hniav tshwj xeeb yuav tsum tau txiav txim siab tom qab sab laj nrog tus kws kho mob ntawm lub tsev kho mob niaj hnub.
Kev xaiv thiab siv cov hlau tsis muaj nuj nqis yog qhov sib txawv hauv ntiaj teb. Tebchaws Asmeskas siv ntau cov nickel chromium alloys; Txawm li cas los xij, hauv Tebchaws Europe thiab Nyij Pooj, cobalt chromium alloy yog siv los kho thiab kho, thiab nws tsis tuaj yeem siv yog tias cov ntsiab lus nickel ntau dua 1 feem pua. Nickel chromium alloy yog yooj yim rau cam khwb cia thiab pheej yig dua li cobalt chromium alloy, tab sis nws lub cev muaj zog thiab corrosion kuj tsis zoo li cobalt chromium alloy. Thaum nws raug rau ib puag ncig thermal, xws li cov plooj (porcelain), cov khoom siv lub cev ntawm cov nickel chromium alloy yuav hloov, thiab cov hlau yuav tsis yooj yim dua thiab tsis haum rau cov txuas hniav ntev. Nyob rau hauv no hais txog, cobalt chromium alloys yog zoo dua li nickel chromium alloys nyob rau hauv tsis kam mus rau kev kho cua sov (Morris 1990, hu nkauj li al. 1999).
Cov kws tshaj lij ntseeg hais tias qhov kev tiv thaiv corrosion nyob rau hauv lub qhov ncauj kab noj hniav: qhov kev ua tau zoo ntawm cov hlau tsis muaj nuj nqis yog qhov txawv ntawm cov hlau muaj txiaj ntsig zoo. Noble hlau alloys yog tsim los ntawm noble hlau kub, platinum, palladium thiab nyiaj. Cov hlau noble muaj cov txheej txheem passivation oxide tsim spontaneously, yog li lawv tuaj yeem tiv thaiv corrosion mus rau qhov zoo. Qhov no kuj tshwm sim hauv kev tso tawm ions. Ntawm cov hlau muaj txiaj ntsig zoo, cov khoom tseem ceeb thiab theem nrab, tshwj xeeb tshaj yog kev sib koom ua ke oxidant thiab zinc, yuav yaj, thaum qhov tshwm sim corrosion ntawm cov hlau tsis muaj nuj nqis yog txiav txim siab los ntawm nws cov ntsiab lus cobalt. Raws li cov kev cai ntawm German kev lag luam tus qauv DIN EN iso10271 ntawm corrosion, ion tso tawm ntawm kub alloy yog qis tshaj, ua raws li titanium, cobalt chromium alloy thiab npib tsib xee chromium alloy.
