Glass-ceramic
[3] The discovery of glass-ceramics is credited to a man named Donald Stookey, a renowned glass scientist who worked at Corning Inc. for 47 years.
[4] While examining the new material, which Stookey aptly named Fotoceram, he took note that it was much stronger than the Fotoform that it was created from as it survived a short fall onto concrete.
[6] In the late 1950s two more glass-ceramic materials would be developed by Stookey, one found use as the radome in the nose cone of missiles,[7] while the other led to the line of consumer kitchenware known as Corningware.
[5] Corning executives announced Stookey's discovery of the latter "new basic material" called Pyroceram which was touted as light, durable, capable of being an electrical insulator and yet thermally shock resistant.
[8] Stookey continued to forge ahead in the discovery of the properties of glass-ceramics as he discovered how to make the material transparent in 1966.
[8] Though Corning would not release a product with his new innovation, for fear of cannibalizing Pyrex sales, until the late 1970s under the name Visions.
[8] The key to engineering a glass-ceramic material is controlling the nucleation and growth of crystals in the base glass.
[4] When enough thermal energy is applied to the system, the metastable glassy phase begins to return to the lower-energy, crystalline state.
The crystal growth process is of considerable importance in determining the morphology of the produced glass ceramic composite material.
[3] Glass-ceramics are used in medical applications due to their unique interaction, or lack thereof, with human body tissue.
Bioceramics are typically placed into the following groups based on their biocompatibility: biopassive (bioinert), bioactive, or resorbable ceramics.
[9] Biopassive (bioinert) ceramics are, as the name suggests, characterized by the limited interaction the material has with the surrounding biological tissue.
[9][10] Osteoinduction is a term used when a material stimulates existing cells to proliferate, causing new bone to grow independently of the implant.
[9] The architecture of these materials has become quite complex, with foam-like scaffolds being introduced to maximize the interfacial area between the implant and body tissue.
[10] One issue that arises from using highly porous materials for bioactive/resorbable implants is the low mechanical strength, especially in load-bearing areas such as the bones in the legs.
[10] An example of a resorbable material that has seen some success is tricalcium phosphate (TCP), however, it too falls short in terms of mechanical strength when used in high-stress areas.
If the glass-ceramic is subjected to a more intense heat treatment, this HQ s.s. transforms into a keatite-solid solution (K s.s., sometimes wrongly named as beta-spodumene).
Glass-ceramic from the LAS system is a mechanically strong material and can sustain repeated and quick temperature changes up to 800–1000 °C.
This allows the use of less extreme processing parameters, making the production of many new technologically important fibre-matrix combinations by sintering possible.
Because it is still a brittle material as glass and ceramics are, it can be broken – in particular it is less robust than traditional cooktops made of steel or cast iron.
There have been instances where users reported damage to their cooktops when the surface was struck with a hard or blunt object (such as a can falling from above or other heavy items).
[15] Compared to conventional kitchen stoves, glass-ceramic cooktops are relatively simple to clean, due to their flat surface.
If food with a high sugar content (such as jam) spills, it should never be allowed to dry on the surface, otherwise damage will occur.
Keralite, manufactured by Vetrotech Saint-Gobain, is a specialty glass-ceramic fire and impact safety rated material for use in fire-rated applications.
Macor is a white, odorless, porcelain-like glass ceramic material and was developed originally to minimize heat transfer during crewed spaceflight by Corning Inc.[18] StellaShine, launched in 2016 by Nippon Electric Glass Co., is a heat-resistant, glass-ceramic material with a thermal shock resistance of up to 800 degrees Celsius.
[19] This was developed as an addition to Nippon's line of heat-resistant cooking range plates along with materials like Neoceram.
KangerTech is an ecigarette manufacturer which began in Shenzhen, China which produces glass ceramic materials and other special hardened-glass applications like vaporizer modification tanks.
[20] The same class of material is also used in Visions and CorningWare glass-ceramic cookware, allowing it to be taken from the freezer directly to the stovetop or oven with no risk of thermal shock while maintaining the transparent look of glassware.
