Editing Glass (section)

==== Glass-ceramics ====
{{Main|Glass-ceramic}}
[[File:Ceranfeld.jpg|thumb|A high-strength glass-ceramic [[cooktop]] with negligible [[thermal expansion]] |alt=A cooktop with two of its eyes turned on]]
[[Glass-ceramic]] materials contain both non-crystalline glass and [[Crystallinity|crystalline]] [[ceramic]] phases. They are formed by controlled nucleation and partial crystallisation of a base glass by heat treatment.<ref name="Holand-glass-ceramics">{{cite book |url=https://books.google.com/books?id=Bw_Yz52jdFQC&pg=PA1 |title=Glass Ceramic Technology |last1=Holand |first1=Wolfram |last2=Beall |first2=George H. |year=2012 |pages=1–38 |publisher=John Wiley & Sons |isbn=978-1-118-26592-5}}</ref> Crystalline grains are often embedded within a non-crystalline intergranular phase of [[grain boundary|grain boundaries]]. Glass-ceramics exhibit advantageous thermal, chemical, biological, and dielectric properties as compared to metals or organic polymers.<ref name=Holand-glass-ceramics />

The most commercially important property of glass-ceramics is their imperviousness to thermal shock. Thus, glass-ceramics have become extremely useful for countertop cooking and industrial processes. The negative [[thermal expansion]] coefficient (CTE) of the crystalline ceramic phase can be balanced with the positive CTE of the glassy phase. At a certain point (~70% crystalline) the glass-ceramic has a net CTE near zero. This type of [[glass-ceramic]] exhibits excellent mechanical properties and can sustain repeated and quick temperature changes up to 1000&nbsp;°C.<ref name="MOD">{{cite book |last=Richerson |first=David W. |title=Modern ceramic engineering : properties, processing and use in design |year=1992 |publisher=Dekker |pages=577–578 |location=New York |isbn=978-0-8247-8634-2 |edition=2nd}}</ref><ref name=Holand-glass-ceramics />