Pushing the Boundaries at Sea

Why Hexcel is Testing Composite Materials to Survive Harsh Saltwater Environments

By Matthew Bates, Director, Marketing & Communications, Americas & Global Fibers

As the U.S. Navy and its allied security partners accelerate the development of unmanned underwater vehicles (UUVs) and unmanned surface vehicles (USVs) to achieve a more distributed and resilient maritime force, the demand for advanced materials that can withstand the harshest ocean environments has never been greater. 

With programs like the Large Unmanned Surface Vehicle (LUSV), Medium Unmanned Surface Vehicle (MUSV), and Extra-Large Unmanned Undersea Vehicle (XLUUV) leading the way, Navy leadership has made clear that uncrewed maritime systems are essential to meeting future threats and expanding operational reach. 

“The Navy wants to develop and acquire [USVs and UUVs] as part of an effort to shift the Navy to a more distributed fleet architecture, meaning a mix of ships that spreads the Navy’s capabilities over an increased number of platforms and avoids concentrating a large portion of the fleet’s overall capability into a relatively small number of high-value ships,”  said Admiral Daryl Caudle, Chief of Naval Operations.

In response, Hexcel is rigorously testing and advancing its composite materials — such as the HexPly^® 8552 system — under real-world saltwater conditions, ensuring these critical platforms can be built with materials that are lighter, stronger, and more durable for the missions ahead.

As global security dynamics evolve, the role of UUVs and other marine applications is becoming increasingly critical to national security,”  said Simon Johnson, Customer Business Team Leader for Hexcel’s Americas & Global Fibers business.  “The Pacific is a very vast environment that the U.S. military has to cover, and it’s really not advantageous to have ships covering all of that space. So having unmanned underwater vehicles and other unmanned surface vehicles in that space is a real advantage.”

At Hexcel’s Research and Technology Center in Salt Lake City, Utah, the Hexcel team has had positive results conducting rigorous saltwater soak testing to simulate long-term exposure to ocean conditions. This testing is critical for understanding and minimizing  “knock down” — the reduction in mechanical properties (such as strength and stiffness) that can occur when composites are exposed to saltwater over time, according to Johnson.

“The saltwater soak data being developed with the 8552 system demonstrates that Hexcel’s composites retain a high percentage of their original mechanical properties even after prolonged immersion,”  he said.  “This means less  ‘knock down’  compared to traditional materials, ensuring that UUVs and USVs built with Hexcel composites maintain their structural integrity, payload capacity, and operational reliability throughout their service life.”

 “We have several customers … that are very interested in our saltwater soak data that we’re developing with our 8552 system,”  added Reid Averill, Technical Development Manager, elaborating on Hexcel’s rigorous testing approach.  “This gives us full control over data quality and test methodology. The marine defense industrial base is going to have confidence when they design different hull systems [with our composites] that it’s going to last the life of the vehicle.” 

By investing in advanced testing and validation, Hexcel is ensuring that its materials meet the demands of the world’s most critical maritime missions — helping the Navy and its allies maintain a decisive edge in an unpredictable world.