Round alumina ceramic discs used as crucible and beaker covers, setter discs or gasket plates for high-temperature laboratory work. Most sizes are made of 99% alumina; four sizes are also offered in 95% alumina. 37 sizes from Ø8 mm to Ø68 mm.
Overview
For high-temperature use: 99% alumina discs withstand up to 1750 °C for demanding laboratory and industrial applications.
Many sizes: diameters from 8 to 68 mm and thicknesses from 1 to 15 mm to fit a wide range of crucibles and beakers.
High-purity ceramic: minimal contamination and excellent thermal stability for precise work.
Cover function: sits securely on crucibles and beakers to prevent spillage and protect samples during heating or storage.
Sold individually: 1 piece per pack.
Key Features
High-purity, dense, uniform alumina without pores, cracks or color differences
Stable corundum structure, long-term use above 1600 °C; low thermal expansion, resists cracking and deformation under rapid heating and cooling
Mohs 9 hardness: excellent wear, erosion and impact resistance; service life over 3× that of ordinary ceramic sheets
Excellent high-temperature electrical insulation; suitable for humid, corrosive and high-pressure environments
Pressed, high-temperature sintered and precision polished: uniform roundness and thickness, high flatness, burr-free edges
