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MACOR®

Machinable Glass Ceramic (MGC)

Special Properties

  • Machinable glass ceramic material
  • Can be machined with conventional metalworking equipment
  • No glass processing machines required
  • Coefficient of thermal expansion is close to many metals and sealing glasses
  • High-temperature resistance
  • Non-porous
  • Dimensionally stable
  • Not outgassing
  • Odorless, opaque white material
  • Sealing with fusing glass possible
  • Good insulator
  • Available as semi-finished rod, bar, and sheet materials

Typical Applications

  • Flight and aerospace industry
  • Substrates for field ion microscopes
  • Ultra-high vacuum and continuous vacuum applications
  • Medical equipment
  • Electrical contact holders
  • Laser cavity components
  • Welding nozzles
  • Bushing tubes
  • Mounting brackets
  • Laser adjustment components
  • High precision workpieces

 

Request for Quotation

 

Finished glass ceramic part made of MACOR®
nullspacer Fig.: Finished mechanical component machined from MACOR® glass ceramic.

 


An extraordinary material, workable almost like metal

MACOR® machinable glass ceramic from CORNING is a white-appearing, odorless, and opaque material. It is composed of a 55% share of MIKA and a 45% share of borosilicate glass. You can find the detailed composition in this data-sheet.

The advanced high-performance Small machined parts made of MACOR® glass ceramic from CORNING glass ceramic offers exceptional properties for a broad range of workpiece designs in the industry. MACOR allows rapid production of complex shapes and precise workpieces with tight tolerances. The CNC-machining of MACOR glass ceramic material can be done with conventional HSS tooling used for metal processing. Hence, expensive glass processing machinery and expensive diamond tools are usually not necessary to process MACOR. You can find out how to handle and process MACOR® correctly in our processing instructions.

 

MACOR® high-tech glass ceramic goes to the limit

The possible long-term use at temperatures of 800°C and a permissible load free peak temperature of up to 1.000°C of MACOR facilitate a wide variety of interesting, sophisticated applications in industries. Corning's unique glass-ceramic has zero porosity and is non-wetting. MACOR® does not deform or outgas and can be used in vacuum environments. The glass ceramic material is an excellent insulator for high voltages and various frequencies even at high operating temperature. MACOR sets an industrial standard for machinable glass ceramics that can hardly be outperformed by other materials. MACOR is therefore frequently used in aerospace, medical technology, semiconductor technology and other demanding applications.

 

From semi-finished material to finished workpiece

MACOR glass ceramic raw-materials are available from stock in the form of sheets, square bars, and round rods at very short lead times. These semi-finished products can be machined to extremely complicated shapes.

 

Components of MACOR® glass ceramic nullspacer You are welcome to request a quotation for a custom finished workpiece made of original MACOR® glass ceramic.


To send an inquiry for any semi-finished standard MACOR® rod, bar, or sheet glass ceramic product or for a finished MACOR® workpiece with individual shape and dimensions, please click the button below:


Request for Quotation

 

Specifications & Properties

 

Density

  • 2,52 g/cm3

Coefficient of Thermal Expansion

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

Thermal Characteristics

  • Continuous operating temp,: 800°C
  • Max. operating temperature: 1.000°C (no load)
  • Thermal Diffusivity (25°C): 7,3 x 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
Very small work pieces of MACOR® glass ceramic nullspacer MACOR® machinable glass ceramic materials from Corning even allow the design of tiny and intricate parts that require to be machined with high precision. If you have any question, please just contact us.

 

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

Semi-Finished Products:

Standard Rods, Bars, & Sheets of MACOR® Glass Ceramic

MACOR® Rods

Rod Diameter
(mm)
Rod lengths
(mm)
3 70
4 70
6 70
8 70
12,5 70
19 75, 150, 300
25 75, 150, 300
30 75, 150, 300
38 75, 150, 300
50 75, 150, 300

MACOR® Bars

Bar Dimension
(mm x mm)
Bar lengths
(mm)
12,5x 12,5 75, 150, 300
19x 19 75, 150, 300
25 x 25 75, 150, 300
30 x 30 75, 150, 300
50 x 50 75, 150, 300

MACOR® Sheets

Sheet size
l x w
(mm)
Sheet thickness
(mm)
75 x 75 12,5, 19, 25, 30, 50
150 x 150 12,5, 19, 25, 30, 50
300 x 300 12,5, 19, 25, 30, 50

The typical lead time for the standard MACOR® glass-ceramic rods, bars, and sheets listed above is approximately one week or less. Only for the larger rod, bar, and sheet materials the lead time can be longer. Please send us your request.


Machining guidelines for MACOR® Glass Ceramic


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

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