This Machineable Ceramic is a white ceramic which can be machined with ordinary steel or carbide tools. It has been used extensively in the Space Shuttle Orbiter.
It can be used continuously up to 800 °C and is a good electrical and thermal insulator. Outgassing in ultra-high vacuum environments can be eliminated, if degassed before use.
MACOR® is non-wetting and can be bonded to itself as well as to various metals, if the MACOR® surfaces are first metallised.
Key Properties
The key properties of MACOR® are tabulated below.
Table 1. Key properties
| Chemical Resistance |
| Acids - concentrated |
Poor |
| Acids - dilute |
Fair |
| Alkalis |
Fair |
| Electrical Properties |
| Dielectric constant |
5.9 |
| Dielectric strength ( kV.mm-1 ) |
40 |
| Volume resistivity ( Ohm.cm ) |
>1014 @ 25 °C |
| Mechanical Properties |
| Compressive strength ( MPa ) |
345 |
| Hardness - Vickers ( kgf.mm-2 ) |
400 |
| Tensile modulus ( GPa ) |
67 |
| Physical Properties |
| Apparent porosity ( % ) |
0 |
| Density ( g.cm-3 ) |
2.52 |
| Thermal Properties |
| Coefficient of thermal expansion ( x10-6 K-1 ) |
13 @ 20-1000 °C |
| Specific heat ( J.K-1.kg-1 ) |
790 @ 25 °C |
| Thermal conductivity ( W.m-1.K-1 ) |
1.5 @ 20 °C |
| Upper continuous use temperature ( °C ) |
800-1000
|
About Goodfellow
Goodfellow supplies metals, ceramics and other materials to meet the research, development and specialist production requirements of science and industry worldwide.
The Goodfellow group consists of four companies. The main administration, research laboratories and workshops are located at the Company's headquarters in Cambridge, England. The subsidiary offices in America, France and Germany provide an additional service.