Durable Advanced Flexible Reusable Surface Insulation

In the past, attempts have been made to use active metals and alloys with fluxing agents to bond metal alloy foils directly to ceramic fabrics. However, these attempts have had less than satisfactory results due to chemical interactions between the ceramic fabric and the braze alloy, lack of wetting of the ceramic fabric, and the difference in the coefficient of thermal expansion of the brazing alloys and the ceramic fabric. Scientists at NASA Ames Research Center have overcome these problems to develop a thermal protection system called Durable Advanced Flexible Reusable Surface Insulation (DuraFRSI). This material is a hybrid metallic/ceramic insulation that provides a thermal protection system of improved durability while still providing adequate thermal protection to structures subjected to multiple cycles of aeroconvective heating. Due to the material's increased durability and impact resistance, DuraFRSI is particularly well-suited for use on the exterior of substrates or structures and other applications that require a rugged insulation.

DuraFRSI is fabricated by sizing the insulation layer smaller than the ceramic fabric and metallic screen layers to form closeout extensions, and securing the closeout extensions to sides of the insulation layer. The interconnecting step includes stitching together one ceramic fabric layer, the insulation layer, and the metallic screen layer. The improved flexible blanket includes a nickel-based alloy foil layer brazed to a nickel-based alloy screen layer which has been previously stitched to an underlying ceramic fabric and insulation layer.

Potential Commercial Uses

• One of the greatest potential uses for DuraFRSI is in the automotive industry. This material may be advantageous as an insulation-protection combination around exhaust manifolds, catalytic converters, firewalls, and mufflers.
  
• Industrial machinery and motors that reach high temperatures could benefit by this flexible yet sturdy insulating material.
  
• DuraFRSI could have outdoor firewall and temperature protection applications where the material would be subject to the elements of nature.

Benefits

• Highly temperature resistant: DuraFRSI offers excellent thermal protection against temperatures in excess of 2000 degrees Fahrenheit.
  
• Thin, flexible, and lightweight: DuraFRSI is thin (.5 inches in thickness), lightweight (8-10 pounds per cubic foot), and is flexible enough to bend and shape as needed in various applications.
  
• Improved durability: Due to the material's metallic surface, it is far more durable than previous insulations used in environments containing conductive, convective, and radiative heating components.
  
• Impact resistant: Previous insulation materials were susceptible to impact damage which has been greatly reduced by the addition of a metallic surface layer. The metallic layer also gives the insulation a smooth, easy-to-maintain surface, and aids in the material's resistance to water absorption.
  
• Mechanically attachable: Due to its metallic top surface, DuraFRSI is mechanically attachable to a substrate using screws or other attachment devices rather than common adhesives.
  
• Adaptable to application: Depending on the intended application and the temperature protection required, the insulation can be fabricated with various materials. For example, DuraFRSI can be manufactured using Inconel which is extremely heat resistant and more expensive, or stainless steel which is less heat resistant and less expensive.
  
• Mass production capabilities: The material can be fabricated in large pieces and cut to size.

Options for Commercialization

NASA Ames currently seeks to license DuraFRSI to companies interested in manufacturing the material for commercial applications. A continuing need exists for materials that are even more durable and resistant to damage; therefore, co-development efforts may be considered with companies capable of improving current thermal protection materials or inventing new methods of fabrication. Licensing options are available.

Contact

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

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

Key Words

Composite Flexible Blanket Insulation, Conductive Heating, Convective Heating, Durable Advanced Flexible Reusable Surface Insulation (DuraFRSI), Radiative Heating, Thermal Protection