Oxide Ceramics ｜Machinable Glass Ceramics

Machinable glass ceramics, also known as microcrystallite glass ceramics, are mica glass-ceramics with synthetic mica as the main crystal phase, and the main components are fluorphlogopite (Mg3K[AlF2O(SiO3)3]) and glass composition with silica as the main component. The material is similar to MACOR. The performance is basically the same.

Machinable ceramics can be drilled, turned, milled, tapped, etc., processed with tools and instruments for metal processing, and ceramic materials with precise dimensions can be obtained. The material has good processing properties, vacuum properties, electrical insulation properties, thermal shock resistance, chemical corrosion resistance and other excellent properties. The machinable ceramic material has excellent electrical insulation properties (electrical breakdown reaches 40KV/A per millimeter), high mechanical strength, resistance to rapid cooling and rapid heating (resistance to rapid cooling and rapid heating of minus 200 degrees to 800 degrees, it is widely used in welding fixtures, optical glass forming molds, etc.). Its corrosion resistance is also better than that of ordinary ceramics. Its excellent corrosion resistance makes it suitable for use in various chemical equipment. Compared with PTFE, it is more corrosion-resistant, does not age, and has a long service life. The vacuum out-gassing rate of the machinable ceramics is extremely low (widely used in various vacuum equipment, photovoltaic vacuum coating equipment, etc.), and the machinable ceramics also have excellent electromagnetic properties, and are now used on a large scale for various types of coil skeletons.

The most prominent feature of machinable glass ceramics is its machinability, which can meet the technical requirements of high precision. It can be directly processed and formed without mold opening, which greatly reduces the design and processing cycle. Machinable ceramics can be flexibly used in various occasions that require complex shapes, high precision requirements, and difficult forming (such as various ceramic thin walls, ceramic threads, etc.).

Color: White
Main features: easy processing, excellent electrical insulation, excellent thermal insulation.
Main uses: electrical insulating parts, thermal insulating parts.

Material Properties of Machinable Glass Ceramics

Parameter	Unit	Value
Color		White
Water Absorption	%	0
Density	g/mm3	2.6
Apparent Porosity		0.069%
Moh’s Hardness		4~5
Flexural Strength	Mpa	94
Compressive Strength	Mpa	345
Young's Modulus	Gpa	66.9
Poisson's Ratio	-	0.29
Linear Expansion Coefficient (40-400℃)	x10-6/℃	9
Thermal Conductivity (20℃)	W/(m·k)	1.46
Specific Heat	J/(kg·k)x103	0.79
Volume Resistivity(20℃)	Ω·cm	1017
Dielectric Strength	KV/mm	45
Dielectric Constant	-	6
Dielectric Loss Coefficient	x10-4	4