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MACOR®

Machinable Glass Ceramic (MGC)

Special Properties

  • Machinable with conventional HSS tools
  • Coefficient of thermal expansion close to many metals and sealing glasses
  • High-temperature resistance
  • Non-porous
  • Dimensionally stable
  • No outgassing
  • Odorless, opaque, white material
  • Excellent electrical insulation properties
  • Available as semi-finished bars, rods, and sheets

Typical Applications

  • High-precision workpieces
  • Contact holders, sockets, bushings, and feedthroughs
  • Aerospace industry
  • Substrates for field ion microscopes
  • Ultra-high vacuum and continuous vacuum applications
  • Medical devices
  • Laser cavity components
  • Insulators for electronic connectors
  • Welding nozzles
  • Bushing tubes
  • Mounting brackets
  • Laser alignment components

Related Ceramic Materials

  • SHAPAL™ Hi M-soft
    (Machinable aluminum nitride ceramics)
  • Al2O3
    (Alumina high-performance ceramics)

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MACOR® machinable glass ceramic from CORNING is a white, odorless, and opaque material consisting of 55 % MIKA and 45 % borosilicate glass. The high-performance Small machined parts made of MACOR® from CORNING glass ceramic offers ideal properties for a wide range of industrial applications. MACOR® can be used to design complex shapes and precise parts with tight tolerances. It can be CNC machined with conventional HSS tools commonly used for metal machining. As a result, no expensive special equipment, machines or diamond tools are generally required to process MACOR®. The processing parameters for MACOR®can be found in our machining guidelines.

Finished part made of MACOR® MGC
nullspacer Figure: A finished part with tight tolerances machined from MACOR® MGC

MACOR® can be used at temperatures of up to 800 °C for long periods of time and withstands up to 1000 °C without load. The unique glass ceramic has zero porosity and is non-wetting. MACOR® does not deform or outgas allowing it to be used in vacuum environments. It is an excellent insulator for high voltages at various frequencies, as it provides low conductivity. MACOR® sets an industrial standard for machinable glass ceramic. It is ideal for a wide range of applications in the aerospace, medical, and semiconductor industries.

Very small parts made of MACOR® nullspacer MACOR machinable glass ceramic allows the design of such tiny and intricate parts with high precision. For a quote, please click here.

 

To get a quote for MACOR® material or a finished part with custom shape and dimensions according to your drawing, please click the button below:

 

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Specifications, Properties & Raw Material

 

Semi-finished MACOR®

Our company stocks MACOR® as sheets, rods, and bars with short lead times. These are the starting point for complex shaped parts.

 Rods
Rod-ø
(mm)		 Available lengths
(mm)
3 | 4 | 5 | 6 | 8 | 12,5 70
19 | 25 | 30 | 38 | 50 75 | 150 | 300
Request a MACOR® -Rod

 Bars
Size
(mm x mm)		 Available lengths
(mm)
12,5 × 12,5


75 | 150 | 300
19 × 19
25 × 25
30 × 30
50 × 50
Request a MACOR® Bar

 Sheets
Size
(mm x mm)		 Available Thicknesses
(mm)
75 × 75
12,5 | 19 | 25 | 30 | 50
150 × 150
300 × 300
Request a MACOR® Sheet

The MACOR® materials above are available in approximately one week or less. Larger dimensions may take longer.

 

MACOR® MGC Machining Guidelines

Density

  • 2,52 g/cm3

Coefficient of Thermal Expansion

  • 74 × 10-7 / °C (-200–25 °C)
  • 93 × 10-7 / °C (25–300 °C)
  • 114 × 10-7 / °C (25–600 °C)
  • 126 × 10-7 / °C (25–800 °C)

Thermal Characteristics

  • Continuous operating temperature: 800 °C
  • Max. operating temperature: 1000 °C (no load)
  • Thermal Diffusivity: (25 °C): 7,3 × 10-7 m2/s
  • Thermal Conductivity: (25 °C): 1,46 W/m°C
  • Specific Heat (25 °C): 0,79 KJ / kg°C

Mechanical Characteristics

  • Porosity: 0 %
  • Young's Modulus: (25 °C): 66,9 GPa
  • Poisson's Ratio: 0,29
  • Shear Modulus: (25 °C): 25,5 GPa
  • Knoop Hardness: (100 g): 250
  • Modulus of Rupture: (25 °C): 94 MPa
  • Compressive Strength: 345 MPa
  • Fracture Toughness: 1,53 MPa m0,5

Electrical Characteristics

  • Dielectric Constant: (25 °C): 6,03 (1 kHz)
  • Dielectric Loss Tangent: (25 °C): 4,7 x 10-3 (1 kHz)
  • Dielectric Strength: (25 °C): 40 kV / mm
    (at 0,254 mm thickness)
  • Volume Resistivity: >1016 Ω-cm

 

Composition of MACOR® Glass Ceramic

Substance approximate weight
percentage
Silicon oxide (SiO2) 46
Magnesium oxide (MgO) 17
Alumina (Al2O3) 16
Potassium oxide (K2O) 10
Boron oxide (B2O3) 7
Fluorine (F) 4

Chemical Properties

Medium

pH

Time
(h)

Temp.
(°C)

Weight loss
(mg/cm2)
5 % HCL
0,1
24 h
95 °C
ca. 100
0,002 N HNO3
2,8
24 h
95 °C
ca. 0,6
0,1 N NaHCO3
8,4
24 h
95 °C
ca. 0,3
0,02 N Na2CO3
10,9
6 h
95 °C
ca. 0,1
5 % NaOH
13,2
6 h
95 °C
ca. 10
H2O (water)
7,6
24 h
95 °C
ca. 0,01
Components made of MACOR® glass ceramic nullspacer

Request precise workpieces made of original MACOR® machinable glass-ceramic according to your specifications here.

 

All details and specifications provided here are mean reference values and are not guaranteed. Also, please consider our "Notes on Specifications".

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Last update: April 16, 2024