Pyroceram is the original glass-ceramic material developed and trademarked by Corning Glass in the 1950s.
Development
Its development has been traced to Corning's work in developing photosensitive glass. Corning credits S. Donald Stookey with its discovery; while conducting research in 1953 on a photosensitive lithium silicate glass called Fotoform containing a dispersion of silver nanoparticles, Stookey noted that an accidentally overheated fragment of the glass resisted breakage when dropped. Stookey's initial glass-ceramic became Fotoceram, with Li2Si2O5 and quartz as its crystalline phases. Fotoceram evolved into Pyroceram in 1959, with β-spodumene as the crystalline phase, which evolved into the CorningWare line of cookware.
The manufacture of the material involves controlled crystallization. NASA classifies it as a glass-ceramic product.
After about 30 years of informal use as a standard in high heat (≥1000°C) applications, Pyroceram 9606 was approved by NIST as a certified reference material for thermal conductivity measurements.