Saving Lives With Ceramic Armor
Over the last few years, ceramic armor has become a booming business. But manufacturers in this sector will be the first to tell you that it's not by any means an easy business, even in the best of circumstances. Extremely cyclical demand, particularly for body armor, has made it difficult to invest in the capital equipment and research and development efforts necessary to advance armor technology. At the same time, a highly competitive environment has made it necessary for companies to continue to find ways to reduce costs while increasing their armor performance and manufacturing capacity.
Despite these challenges, companies in this business take their responsibilities to their customers very seriously. As Joel Moskowitz, Ceradyne, Inc.'s chief executive officer, expressed, "Ceradyne is committed to redirecting its efforts on a priority basis, whenever needed, to assure our soldiers have the finest protection available. Recent input from the military indicates that lightweight ceramic armor is directly responsible for saving American lives in Afghanistan, Bosnia, Kosovo and the Middle East.... Our company takes great pride in directly saving American lives through our soldiers' use of lightweight ceramic armor."
This commitment on the part of Ceradyne and other ceramic armor manufacturers has resulted in some significant technological advances, as well as some promising research that could lead to even more improvements in the near future.
Recent DevelopmentsPrior to the late 1990s, body armor was very heavy. Even the "advanced" aluminum oxide armor worn by soldiers in the 1993 operation in Mogadishu, Somalia, weighed an average of 25 lbs for a complete set. This reduced the soldiers' mobility and dramatically increased their fatigue, resulting in decreased fighting capability and increased casualties. Although lighter weight ceramic armor was available, the manufacturing costs-and therefore purchasing costs-were very high.
In 1997, the U.S. Army Manufacturing Technology (ManTech) Program (a cost-sharing research and development initiative) embarked on a project to develop processes for the economical mass production of boron carbide (B4C) and siliconized silicon carbide (Si/SiC) Small Arms Protective Insert (SAPI) armor plates, which were designed to be used in the Interceptor Body Armor (IBA) system. Initial participants in the project included the U.S. Marine Corps; the U.S. Army Soldier & Biological Chemical Command; Specialty Defense Systems; Simula Inc.; and Cercom Inc., a manufacturer of advanced materials such as B4C and SiC. Other ceramic manufacturers, such as M Cubed Technologies Inc., Ceradyne Inc. and CoorsTek also got involved as the project progressed.
Through the ManTech effort, the cost of B4C plates was reduced from an average of $850 per plate to $525 per plate by 2001, and processes were refined to produce functionally equivalent Si/SiC plates at an average cost of only $350 per plate. By 2002, the cost of Si/SiC plates had been reduced even further. Combined with the soft outer tactical vest (OTV) that comprises the IBA, these new plates brought the total cost of IBA into the $1500-$1700 range. Although this was still higher than what the Department of Defense had been paying for conventional aluminum oxide armor, the new plates were about 55 percent lighter, weighing an average of 10 lbs less than the conventional armor materials.
"The Interceptor Body Armor system was the first new armor that the Marine Corps and Army have had since Vietnam in the 1960s. Because it's B4C (and, in some cases, SiC) instead of aluminum oxide, it's much lighter. That's the justification for the high price, and the government is more than willing to pay that price because they're beginning to understand the impact of weight on a soldier in the field," said Richard Palicka, president of Cercom.
The performance of B4C and SiC materials was also improved through the ManTech effort, increasing the IBA's ability to protect soldiers' lives. "Multi-hit protection has been the real Achilles heel of ceramic because of its fracture behavior. We can't eliminate this behavior, because it's actually a key energy-absorbing process. But we do need to limit crack propagation, because the presence of a large amount of cracking reduces the performance of the ceramic for subsequent hits," explained Dave Puckett, director of armor programs for Ceradyne, Inc.
In the past, manufacturers tried to overcome this problem by creating a tile mosaic. However, even this solution had drawbacks. "Although the tile mosaic design works, it is expensive because the interfaces between the tiles need to be precisely made. Additionally, it is extremely difficult to design a tile mosaic system with uniform performance. Instead, you have to design for the weakest link, so your armor system winds up being heavier than it needs to be," Puckett said. "By modifying the microstructure of the ceramic material to better dissipate the energy of the projectile, as well as by using different composite backings, we have been able to design better armor with very good multiple hit performance using a monolithic approach."
Companies such as M Cubed Technologies also brought valuable materials expertise to these advances. "Reaction-bonded SiC has been made for years, but we had altered the microstructure to make it very fine grained for the manufacture of precision machined components for the semiconductor market, and we were able to demonstrate that the same fine-grained microstructure also resulted in very good ballistic performance in armor applications. By combining that expertise with our ability to make very large, complex shapes and our ability to scale that to large volumes in a manufacturing environment, we've been able to help meet the demand for lightweight, high-performing, cost-effective armor," said Tom Holmes, director of Armor Sales and Marketing for M Cubed Technologies.
By early 2001, the U.S. government had procured more than 30,000 of the new plates and had another 130,000 on contract. It wasn't long before the new armor was tested in combat-U.S. troops first wore the IBA system in operations in Afghanistan, where it was credited with saving numerous lives. According to one report, some soldiers pinned down in firefights survived AK-47 and other small-arms fire to their chest and back because of the new vest, and most of the wounds suffered by U.S. troops were in the arms and legs. Many of these same systems have been credited with saving soldiers' lives in Operation Iraqi Freedom.
Promising R&DAs a result of the SAPI plates' success, orders for the plates skyrocketed in 2002 and 2003. But further improvements are still needed in weight and cost reductions and in enhanced ballistics performance. Ceramic armor manufacturers, universities and government organizations are all trying to develop these improvements, both individually and through collaborations.
For instance, under Small Business Innovation Research (SBIR) funding through the U.S. Army, Ceradyne is working to develop boron-rich boron carbide, which would contain more than four borons per carbon (B4C). "Because boron is quite carbon-hungry at sintering temperatures, some of it is depleted during sintering because of the abundance of carbon in the tooling used in the sintering process, and it's difficult to achieve a richer than B4C stoichiometric ratio. However, researchers have found that if they can preserve that B4C, or even push toward something more like B5C, and preserve it through processing, it will pay dividends in strength and toughness," said Puckett.
Ceradyne is also working to develop a stronger, lower-cost reaction-bonded SiC material; enhanced processing methods for hot-pressed siliconized silicon carbide that would provide increased tool life, lower power costs and better cycle times; and better armor designs. The company also hopes to be able to introduce a lightweight ceramic helmet within the next several years.
Cercom is focusing much of its body armor efforts on reducing the weight of the SAPI plates through improved backing materials and better dimensional control of the ceramics, while also increasing the plates' multi-hit performance. According to Palicka, the company already offers what it calls an "enhanced SAPI plate," which features greatly improved multi-hit capabilities at closer shot spaces, but work is ongoing to address heavier threats, such as sniper rounds and armor-piercing rounds, with lighter weight ceramics.
These advances are also pushing aluminum oxide armor manufacturers to enhance the performance of their products. For instance, CoorsTek has developed a lightweight body armor plate out of aluminum oxide that meets the tight size and shape requirements for the SAPI application, and the company is continuing to work on further improvements in this area. Because of the lower cost of aluminum oxide, such developments could lead to increased demand for aluminum oxide body armor in the future.
However, according to Palicka, the biggest opportunities for ceramic armor aren't in body armor, but in vehicle armor. "A good portion of a vehicle's weight is armor, so there's a lot of work being done right now on ceramics for lightweight vehicles, such as the Marine Corps' Armored Amphibious Assault Vehicle (AAAV). That's something we're working on, along with other companies. Future combat systems are also under development," he said.
CoorsTek and M Cubed Technologies are also developing products for military vehicles and aircraft. According to Eric Davenport, general sales manager for CoorsTek's armor facility, the company is already in the second year of a significant light armored vehicle (LAV) program and expects to see results emerging soon.
M Cubed Technologies recently introduced a new reaction-bonded boron carbide product with similar advantages to its reaction-bonded SiC product. "It's a boron carbide material, but by using a reaction-bonded process, we can make shapes and sizes that you're just not capable of making with the typical hot-pressed boron carbide that you see on the market," said Holmes. "Over the next two to three years, the military is going to increasingly adopt armor systems that take advantage of the benefits that one-piece complex reaction-bonded SiC and B4C can offer."
For example, a one-piece helicopter seat using M Cubed Technologies' reaction-bonded B4C technology is providing several key advantages compared to conventional seat designs. "Traditionally, companies made multi-piece tiles, and those would be assembled at the armory integrator. A one-piece design helps reduce the weight of the seat, as well as the labor costs for assembly," Holmes said.
While many researchers believe that B4C holds a great deal of promise for vehicle applications, a major impediment to using B4C for vehicle armor is its high-impact pressure amorphization-i.e., B4C does an excellent job of blocking low-energy projectiles such as handgun bullets, but it transforms to a glassy material at extremely high velocities and pressure, causing it to shatter. This effect was recently discovered by researchers from The Johns Hopkins University and the U.S. Army Research Laboratory. Having found why boron carbide abruptly loses its protective capabilities, the researchers hope they have opened a door toward developing a new form of the material that will do a better job of keeping soldiers and police officers safe. If it could stand up to higher-energy threats, military experts believe that B4C, whose hardness approaches that of diamond, would find greater use as a lightweight armor material for military, police, diplomatic and other vehicles.
However, many companies believe that silicon carbide or alumina will continue to be better materials for most vehicle armor applications. "Where boron carbide gets weaker under impact, the silicon carbide we make actually gets stronger the harder you hit it, at least to a point. Unless someone performs miracles with boron carbide, silicon carbide will probably be the material of choice for vehicle armor," said Palicka.
Alumina's low cost and continued improvements also make it a potentially fierce competitor in this area. "On a cost per pound basis, other materials are orders of magnitude higher in cost than alumina. Although it is denser than SiC and B4C, alumina is reportedly producing better multi-hit capability and is the most cost-effective solution," Davenport said.
Overcoming ChallengesDespite the recent spike in orders, particularly for body armor, manufacturing ceramic armor continues to be a challenging business. The extremely cyclical demand for body armor has made it difficult for companies to invest in the research and development efforts necessary to advance armor technology. According to Puckett, more collaboration among the industry, university and government players is needed to overcome this problem. "The ceramic body armor industry has really been hurt over the last 20 years by the up and down interest. As a result, management has to take a very conservative approach to investment because they're not sure when orders are going to drop again. There has been research continuously over the years in body armor, but it's been at a low level and generally hasn't been brought to a real focused conclusion. We need more long-term plans and collaborative efforts that involve the government as the user, academia as the brains, and the commercial industry as the business and voice of practicality behind it all," he said.
For the most part, companies in this industry have learned to adjust to the cyclical market by diversifying their product line and customer base and streamlining their manufacturing processes. Many ceramic armor manufacturers supply more than one type of armor in a range of materials, and some also maintain a broad base of export customers. Companies have also implemented lean manufacturing and other efficient manufacturing initiatives to try to lower costs while increasing flexibility.
Accurately predicting market shifts is another strategy that has helped armor manufacturers remain successful. "The last several years for armor sales have been challenging in terms of the amount of material we can put out. This year, especially, we've really stepped up and met a huge demand. But we're not necessarily counting on shipping at the same level through next year. Our challenge as an organization is to predict when the market will decline and what the product mix is going to be then," Davenport said.
"There's not much we as manufacturers can do to change the cyclical effect of the market. We have to do our best to meet our customers' demands and work within the market environment in which we choose to participate," he added.
For now, at least, it appears likely that the market for ceramic body armor will remain strong. "Based on what's happened in Afghanistan and Iraq, the importance of good, lightweight body armor is cemented within the future of the military. There were so many people whose lives were saved because they were wearing ceramic armor that there's no question now that it's a life-saving technology," said Puckett. "In Somalia, the attitude of a lot of soldiers was, ‘Armor is too heavy, it affects my mobility and I'm not sure that it's really going to work anyway.' If you look at any of the news footage now, though, you don't see soldiers not wearing their armor. They know that it works and that it will save their lives if they get hit."
The market for vehicle armor looks even more promising over the next several years. As advances in body and vehicle armor continue to be made, it is likely that an even greater number of lives will be saved in the future.
For more information:For more information about the topics discussed in this article, contact:
• CoorsTek, 600 Ninth St., Golden, CO 80401; (800) 821-6110; fax (303) 277-4596; or visit http://www.coorstek.com.
• Johns Hopkins Department of Mechanical Engineering, http://www.me.jhu.edu.
• U.S. Army Research Laboratory, http://www.arl.army.mil.