Corrosion-fighting rubber could extend life of Marines’ amphibious vehicles

The Navy Research Lab says polyureas rubber also protects against ballistics.

Marines amphibious assault vehicle

The Marines’ ship-to-shore vehicles can corrode after being in the water.


The Navy Research Laboratory is working with a rare type of rubber for the Marine Corps’ amphibious assault vehicles that not only protects against corrosion, but potentially protects against ballistics, too. NRL researchers said the rubber solution will prolong the life of the AAV, which has been in use since 1972, until around 2035. 

The Marines had been bolting armor to their AAVs, which serve to transport soldiers from ship to shore in highly contested environments, for the last 25 years. However, the process of armoring the vehicles was not very efficient. It included a layer of laminate high hard steel, which is good for ballistics protection, a rubber layer and another soft steel layer. Because AAVs operate both on land and in water—giving the Marines a capability no other service has—the armor gets corroded with exposure to water and the corrosion engenders cracks.   

"You've got steel, rubber, steel—and these things are thermally expanding and contracting differently," said Dr. Mike Roland, who along with Dr. Ray Gamache led the research at NRL. "In addition to which, AAVs aren't driven like expensive Volvos; they're banging into stuff—and now you've got a way for water ingress."

Specific types of rubber called polyureas showcased by NRL are better at protecting the armor because they stretch with it rather than cracking. Polyurea coatings slow bullets and blast fragments as “[t]hey take kinetic energy from the bullet...[s]o the bullet, to keep penetrating, it's meeting an increasingly resistant medium,” Roland said. “And if it slows down enough—it always makes it to the steel plate, but it doesn't have enough velocity to get through it."

The Marines’ AAV had been slated to be replaced by a newer ship-to-shore transport vehicle called the Expeditionary Fighting Vehicle, but after cost growth and poor test performances, that program was cancelled in 2011. Following the demise of the EFV program, the Marines and Congress decided to focus on the more modest Amphibious Combat Vehicle program to replace the 40-year-old AAV, though the AAV will continue to be used until a suitable replacement is fully developed.

Polyureas can be found in pickup truck bed-liners, despite not being as common as other conventional rubbers. The combination of chemical bonds found in polyureas greatly contributes to its functionality for NRL’s purpose. Polyureas have more hydrogen bonding, which is a weaker chemical bond than covalent bonds, which makes them more flexible and pliable. Moreover, hydrogen bonds enable the rubber to reform.   

"In conventional materials, you can have something that's really stiff but doesn't stretch much; or you can have something really soft, like silly putty, and it stretches a lot," Roland said. "Polyureas, they can stretch to 10 times their original length, but the force it takes to do that is enormous—so you get toughness, the best of both worlds."

X
This website uses cookies to enhance user experience and to analyze performance and traffic on our website. We also share information about your use of our site with our social media, advertising and analytics partners. Learn More / Do Not Sell My Personal Information
Accept Cookies
X
Cookie Preferences Cookie List

Do Not Sell My Personal Information

When you visit our website, we store cookies on your browser to collect information. The information collected might relate to you, your preferences or your device, and is mostly used to make the site work as you expect it to and to provide a more personalized web experience. However, you can choose not to allow certain types of cookies, which may impact your experience of the site and the services we are able to offer. Click on the different category headings to find out more and change our default settings according to your preference. You cannot opt-out of our First Party Strictly Necessary Cookies as they are deployed in order to ensure the proper functioning of our website (such as prompting the cookie banner and remembering your settings, to log into your account, to redirect you when you log out, etc.). For more information about the First and Third Party Cookies used please follow this link.

Allow All Cookies

Manage Consent Preferences

Strictly Necessary Cookies - Always Active

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Sale of Personal Data, Targeting & Social Media Cookies

Under the California Consumer Privacy Act, you have the right to opt-out of the sale of your personal information to third parties. These cookies collect information for analytics and to personalize your experience with targeted ads. You may exercise your right to opt out of the sale of personal information by using this toggle switch. If you opt out we will not be able to offer you personalised ads and will not hand over your personal information to any third parties. Additionally, you may contact our legal department for further clarification about your rights as a California consumer by using this Exercise My Rights link

If you have enabled privacy controls on your browser (such as a plugin), we have to take that as a valid request to opt-out. Therefore we would not be able to track your activity through the web. This may affect our ability to personalize ads according to your preferences.

Targeting cookies may be set through our site by our advertising partners. They may be used by those companies to build a profile of your interests and show you relevant adverts on other sites. They do not store directly personal information, but are based on uniquely identifying your browser and internet device. If you do not allow these cookies, you will experience less targeted advertising.

Social media cookies are set by a range of social media services that we have added to the site to enable you to share our content with your friends and networks. They are capable of tracking your browser across other sites and building up a profile of your interests. This may impact the content and messages you see on other websites you visit. If you do not allow these cookies you may not be able to use or see these sharing tools.

If you want to opt out of all of our lead reports and lists, please submit a privacy request at our Do Not Sell page.

Save Settings
Cookie Preferences Cookie List

Cookie List

A cookie is a small piece of data (text file) that a website – when visited by a user – asks your browser to store on your device in order to remember information about you, such as your language preference or login information. Those cookies are set by us and called first-party cookies. We also use third-party cookies – which are cookies from a domain different than the domain of the website you are visiting – for our advertising and marketing efforts. More specifically, we use cookies and other tracking technologies for the following purposes:

Strictly Necessary Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Functional Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Performance Cookies

We do not allow you to opt-out of our certain cookies, as they are necessary to ensure the proper functioning of our website (such as prompting our cookie banner and remembering your privacy choices) and/or to monitor site performance. These cookies are not used in a way that constitutes a “sale” of your data under the CCPA. You can set your browser to block or alert you about these cookies, but some parts of the site will not work as intended if you do so. You can usually find these settings in the Options or Preferences menu of your browser. Visit www.allaboutcookies.org to learn more.

Sale of Personal Data

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.

Social Media Cookies

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.

Targeting Cookies

We also use cookies to personalize your experience on our websites, including by determining the most relevant content and advertisements to show you, and to monitor site traffic and performance, so that we may improve our websites and your experience. You may opt out of our use of such cookies (and the associated “sale” of your Personal Information) by using this toggle switch. You will still see some advertising, regardless of your selection. Because we do not track you across different devices, browsers and GEMG properties, your selection will take effect only on this browser, this device and this website.