Spinel Glass Ceramics

9 the phase assemblage consists of spinel solid solution crystals dispersed throughout a continuous.

Spinel glass ceramics. Nesium aluminate spinel is a polycrystalline ceramic material that has excellent optical and mechanical properties. The infrared spectrum of spinel glass ceramics was labeled as gc1. Optical quality transparent spinel has been produced by sinter hip hot pressing and hot press hip operations and it has been shown that the use of a. Spinel is therefore an excellent candidate for transparent armor.

The advantage is it s so much tougher stronger harder than glass says. 2 2 12 sio 2 al 2 o 3 sro bao sr feldspar. Naval research laboratory nrl has been researching over the last 10 years. 2 2 8 1 spinel glass ceramic without β quartz 105.

Glass ceramics based on spinel compositions ranging from gahnite znal 2 o 4 toward spinel mgal 2 o 4 can be crystallized using zro 2 and or tio 2 as nucleating agents. The spectrum shows that the spectral absorption bands at 464 cm 1 556 cm 1 867 cm 1 and 1073 cm 1 were weak the sio 4 structural unit stretched vibrational absorption band almost disappeared and the glass network skeleton was damaged severely. Whereas with glass a crack that forms on the surface will go all the way through spinel. Except it s not glass it s a special ceramic called spinel that the u s.

Transparent refractory glass ceramics based on 10 nm crystals of spinel solid solution in a highly siliceous residual glass can be produced from compositions in the sio 2 al 2 o 3 zno mgo tio 2 zro 2 system. These glass ceramics can be made highly transparent with spinel crystals on the order of 10 50 nm in size fig. The glass ceramics possess excellent chemical durability as well as thermal expansion coefficients of 35 40 10 7 c and strain point temperatures of over 900 c. Imagine a glass window that s tough like armor a camera lens that doesn t get scratched in a sand storm or a smart phone that doesn t break when dropped.

Magnesium aluminate spinel mgal 2 o 4 is a transparent ceramic with a cubic crystal structure with an excellent optical transmission from 0 2 to 5 5 micrometers in its polycrystalline form. It transmits from 0 2 to 5 5 µm and bal listic testing has shown that 1 4 in. Ion exchangeable transparent spinel glass ceramics are presented and discussed here for the first time. To retain transparency with increasing crystallinity spinel glass ceramics must have uniform crystallization of small 9 nm crystallites not large spherulitic structures comprised of small crystallites.

From the above. Crystalline phases β spodumene and spinel of glass ceramic interlayer after joining to si 3 n 4 in situ formed in the joint seam. 2 2 11 sio 2 ga 2 o 3 al 2 o 3 li 2 o na 2 o k 2 o li al gallate spinel 114. 2 2 10 sio 2 al 2 o 3 k 2 o leucite 111.

The spinel nrl makes is a polycrystalline material or a lot of crystal particles all pressed together. 3 the formation of infiltration layer was mainly attributed to the good wettability of glass on the p si 3 n 4. 2 2 8 2 β quartz spinel glass ceramics 107.