What other methods have been used to detect damage and water in composites?

Many fluorescence techniques have been developed over the years as damage sensors, or pressure sensors, for polymers, paints and coatings. More recently, research groups in many different countries including the United States, most notably Jeffrey Moore’s group at the University of Illinois, have made advancements to sense mechanical damage in polymers by developing mechanochromic compounds, or mechanophores. However, researchers have reported far fewer water-sensors, or aquaphores. Our approach focuses on incorporating the mechanophore or aquaphore at the interface between the fiber and the matrix because of the fundamental importance of understanding the interface in composites.

What void does this damage-detecting process fill in the composites industry?

One of the applications for this type of damage sensor could be in health monitoring of composites such as windmill blades, as well as in transportation vehicle body panels. Another application for both the damage-sensing and water-sensing capability is in product development and in developing structure-property and processing-property data about the composite interface.

Where can composites research support efforts take the industry in the near future?

For 2013, the composite materials market was estimated at about $7 billion with 2,132 metric tons of product.  Estimates are for growth to about $10 billion by 2019. Beyond the growth of the materials market is the impact throughout the economy. NIST and the industry recognize the pervasiveness of materials across numerous industries – these materials markets are serving major segments of the U.S. economy – namely transportation/automotive aerospace, energy (wind and gas/oil) and construction.  While improvements in materials cannot claim all growth in these sectors, these sectors represent an important portion of the overall economy.

In general, the goal of these NIST grants, which support road mapping activities, is to influence both the size and scope of industry growth and to accelerate that growth.  Having relevant stakeholders identify the technical challenges early helps create opportunities for new applications and reduces the time to market for products already under development.