Machineable Glass Ceramic - SiO2 46/Al2O3 16/ MgO 17/K2O 10/B2O3 7

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.

Citations

Please use one of the following formats to cite this article in your essay, paper or report:

  • APA

    Goodfellow. (2024, June 04). Machineable Glass Ceramic - SiO2 46/Al2O3 16/ MgO 17/K2O 10/B2O3 7. AZoM. Retrieved on July 19, 2024 from https://www.azom.com/article.aspx?ArticleID=2266.

  • MLA

    Goodfellow. "Machineable Glass Ceramic - SiO2 46/Al2O3 16/ MgO 17/K2O 10/B2O3 7". AZoM. 19 July 2024. <https://www.azom.com/article.aspx?ArticleID=2266>.

  • Chicago

    Goodfellow. "Machineable Glass Ceramic - SiO2 46/Al2O3 16/ MgO 17/K2O 10/B2O3 7". AZoM. https://www.azom.com/article.aspx?ArticleID=2266. (accessed July 19, 2024).

  • Harvard

    Goodfellow. 2024. Machineable Glass Ceramic - SiO2 46/Al2O3 16/ MgO 17/K2O 10/B2O3 7. AZoM, viewed 19 July 2024, https://www.azom.com/article.aspx?ArticleID=2266.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Your comment type
Submit

While we only use edited and approved content for Azthena answers, it may on occasions provide incorrect responses. Please confirm any data provided with the related suppliers or authors. We do not provide medical advice, if you search for medical information you must always consult a medical professional before acting on any information provided.

Your questions, but not your email details will be shared with OpenAI and retained for 30 days in accordance with their privacy principles.

Please do not ask questions that use sensitive or confidential information.

Read the full Terms & Conditions.