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MACOR®

Machinable Glass Ceramic (MGC)

Special Properties

  • Can be machined with standard HSS tools for metalworking
  • High temperature resistance
  • Non-porous
  • Dimensionally stable
  • No outgassing
  • Odorless, opaque, white material
  • Excellent electrical insulator
  • Coefficient of thermal expansion close to that of many metals and sealing glasses
  • Available as semi-finished bars, rods, and sheets
  • Radiation resistant
  • No post firing required

Typical Applications

  • High-precision workpieces
  • Contact holders, sockets, bushings, and feedthroughs
  • Aerospace industry
  • Equipment for field ion microscopes
  • Ultra-high vacuum and continuous vacuum applications
  • Medical devices
  • Laser cavity components
  • Insulators for electronic connectors
  • Semiconductor and electronics applications
  • Nuclear research
  • 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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What is MACOR®?

MACOR® is a machinable glass ceramic (MGC) made by CORNING. It 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 material has 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 machining metal. As a result, no expensive special equipment, machines, or diamond tools are generally required to process MACOR®.

 

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

 

What is special with MACOR®?

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, so it can also be used in vacuum environments. It does not require post firing. Moreover, it is an excellent insulator for high voltages at various frequencies, as it provides low conductivity. MACOR® MGC 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.

 

How do I get a quote for MACOR®?

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,
and Raw Materials

 

Semi-finished MACOR® materials

We stock sheets, rods, and bars with short lead times. These are the starting points 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
Get a quote for 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
Get a quote for a MACOR bar

Sheets

Size
(mm x mm)
Available Thicknesses
(mm)
75 × 75
12.5 | 19 | 25 | 30 | 50
150 × 150
300 × 300
Get a quote for a MACOR sheet

The materials above are typically available in one week or less. Larger dimensions may take a little 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
approx. 100
0.002 N HNO3
2.8
24 h
95 °C
approx. 0.6
0.1 N NaHCO3
8.4
24 h
95 °C
approx. 0.3
0.02 N Na2CO3
10.9
6 h
95 °C
approx. 0.1
5% NaOH
13.2
6 h
95 °C
approx. 10
H2O (water)
7.6
24 h
95 °C
approx. 0.01
Components made of MACOR® glass ceramic nullspacer

Precise workpieces made of original MACOR®machinable glass-ceramic.

 

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

© 1994 – 2024 Präzisions Glas & Optik GmbH

Last update: June 10, 2024