Robust Sensors Detect Material Ablation and Temperature Changes

Robust Sensors Detect Material Ablation and Temperature Changes (LEW-TOPS-83)
Embedded and arrayed sensors enable large-area sensing in thermal protection systems and more
Innovators at NASA's Glenn Research Center developed a microsensor suite to measure real-time changes in thickness and temperature on the surface of a material undergoing ablation. Corrosion, ablation, attrition, and erosion are examples of material damage that affects surface integrity and product performance and could compromise safety of lives and property. The ability to reliably and efficiently monitor the temperature and rate at which surface materials deteriorate is important, especially for safety critical systems. Originally designed for use in thermal protection systems (TPS) of space vehicles, these embedded and distributed sensors foster large-area sensing. Glenn's development also holds great potential for monitoring accelerated attrition rate caused by the high velocity flow of liquid-sand or other mixtures through pipes. Real-time monitoring of these conditions will enable optimal product performance before replacement.

The Technology
Glenn's breakthrough technology introduces batch-fabricated, miniature sensors embedded and distributed over a large surface area of a material or product during the manufacturing process. The sensors can be utilized for test instrumentation or as an integrated in-situ monitoring system. This integrated manufacturing approach preserves the structural and mechanical system integrity by eliminating the antiquated plug-in approach, invasive machining, manual insertion, and gluing processes currently required to implant sensors into a material. The sensor ladder network of resistors and capacitors breaks down as result of the thermo-physical effects caused by temperature, shock, radiation, corrosion, or other reactions, causing a change in the electrical properties. A processor interprets these changes in the electrical properties and generates a high-resolution, large-area surface profile. The profile demonstrates the amount or rate of material deterioration and temperature change, and is used to optimize geometric structural design, develop materials, predict performance, and make decisions. These sensors play an important role as industries work to realize material performance and product design. This type of monitoring is ideal for infrastructures, nuclear enclosures, or any system susceptible to surface deterioration.
This technology can identify dangerous degradation in a vehicle's brake system
  • Efficient: Embeds sensors and telemetry during the manufacturing process, eliminating the expensive and time-consuming practice of manually inserting thermocouples and resistors into materials
  • Versatile: Allows numerous sensors to be implanted for high-resolution/large-area profiling
  • Compact: Allows for miniaturized, lightweight, micron scale sensor networks
  • Reliable: Optimizes material and product development to increase performance and prioritize safety
  • Economical: Batch fabrication results in lower costs

  • Vehicles (braking systems)
  • Thermal protection systems (space vehicles, missiles, hyper-loop vessels)
  • Oil and gas (pipe erosion)
  • System monitoring (nuclear containment, infrastructure erosion)
Technology Details

LEW-18771-1 LEW-18771-2
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