Protective Coating For Ceramic Materials

A new protective coating for ceramic materials has been developed at NASA Ames. The coating lowers the surface temperature of the thermal control structure and reduces heat transfer through the surface preventing degradation of the underlying ceramic material. The new coating provides increased total hemispherical emissivity and decreased catalytic efficiency of the thermal control structure surface when subjected to a high temperature environment. NASA's primary application of this protective coating is for ceramic materials used in heat shields for space vehicles. The coating for protecting ceramic substrates is prepared by first forming a slurry of the components, then ball milling the slurry to provide a uniform solid dispersion. The slurry is then placed in an appropriate storage container and rotated on a Kendall or equivalent mixer until just prior to application onto a ceramic material. The coating is applied with conventional brushes and air dried; no additional heating is required.

Potential Commercial Uses

• Coatings for firefighting equipment such as fire shelters, lightweight tents, hoses, and other tools.
  
• Roof coating for houses and buildings located in high fire-danger areas.
  
• Coated tarps could protect stored objects from extreme heat.
  
• Heat resistant, fireproof insulating cover for bundles of electrical wiring, and for hoses or pipes that carry volatile fluids or gasses.
  
• Use in the manufacturing of safes and safety deposit boxes for adding extreme heat protection.
  
• Environmentally friendly protective coating could be packaged for distribution to contractors, construction companies, and hardware stores.

Benefits

• Extreme heat resistant: Capability of surviving cyclic heating to 1600 degrees C (2910 degrees F)
  
• Physically tough: Good thermal shock, vibration and acoustic performance while resistant to abrasion and mechanical damage.
  
• Lightweight and flexible: Coating can be applied thinly in order to retain the flexibility of a coated fabric, at the same time avoiding additional excessive weight on the coated material.
  
• Easily formulated: The protective coating is a formulation of three readily available materials and can be produced with minimal equipment.
  
• Environmentally safe: The coating is water-based and contains no solvents.
  
• Continuing development: The coating was developed for use on ceramic fabrics, but on-going tests show the coating could be effective on other materials.

Options for Commercialization

NASA Ames is currently seeking partnerships with industry to further develop Protective Coating utilities. Licensing options are also available for the manufacture and distribution of the Protective Coating for specific and general applications. Protective Coating for Ceramic Materials, developed by Kourtides et al, was issued U.S. Patent # 5,296,288 on March 22, 1994.

Contact

NASA Ames Research Center
Commercial Technology Office
Mail Stop 202A-3
Moffett Field, CA 94035-1000
Phone: (650)-604-0625
Fax: (650)-604-1592

http://ctoserver.arc.nasa.gov:80/TechOpps/pccm.html

Key Words

Extreme Temperature Insulation, Fire Equipment, Fire Protection, Protective Coating for Ceramic Materials, Thermal Insulation.