AMAG AL4® Defense

AL4® Defense Armor plates for protection against impacts

One of the most compelling applications for high-performance aluminium is in the manufacturing of armor plates. These high-strength components are engineered to absorb and dissipate the massive kinetic energy from ballistic threats and explosive devices. Serving as a critical shield, these plates protect the personnel, vehicles, and strategic infrastructure behind them. Because effective armor must withstand high-velocity impacts, the plates are often substantial in thickness. At this scale, the weight-saving benefits of aluminium become a strategic game-changer – enabling heavy protection without compromising the payload or manoeuvrability of transport vehicles and personnel carriers. Furthermore, aluminium’s inherent corrosion resistance ensures long-term structural integrity in the harshest environments, like maritime environments.The alloys used for armor plates must undergo ballistic tests as per the specifications mentioned above. These ballistic tests involve shooting a specified projectile at a given velocity (dependent on the plate thickness) towards the target armor plate. The test is passed when the velocity at which the projectile penetration chance is 50% (v50), is higher than the minimum prescribed velocity in the specification for a given plate thickness. There are two main types of projectiles used in these tests – AP (Armor Piercing Ammunition – sharp nosed projectile) and FSP (Fragment Simulating Projectile – blunt nosed projectile). The type of projectile determines the critical mechanical properties for success – AP projectile impact requires material with high strength whereas FSP projectile impact requires a material with higher ductility along with sufficient strength. In the following, we see the different AMAG alloys being used for armor plate applications:

6061 Plates – machinable & heat treatable armor plates offering flexibility

This alloy is delivered by AMAG in the thickness ranges as mentioned in the table above, meticulously produced as per the military standard MIL-DTL-32262. Owing to its wide field of application this alloy must withstand different projectile types for different plate thicknesses upon laboratory testing.Especially when resistance against both projectile types is demanded - AP projectile and FSP projectile - extremely precise balance of high strength and ductility is needed. At AMAG, we achieve this through our highly controlled heat-treatments for thick plates which is backed by our in-depth knowledge of aircraft plate manufacturing. This way we can ensure that we reach the targeted mechanical properties depending on the expected ballistic threats. This adaptability combined with 6061 alloy’s corrosion resistance ensures that 6061 alloy from AMAG provides long term protection even in harsh environments. The plates can also be cut into specific contours as per the customer’s request, maximizing yield during machining steps and contributing to a perfect recycling loop for the offcuts that remain at AMAG.

7020 Plates – high strength armor plates for top-tier protection

Among armor plate alloys produced at AMAG, the 7020 alloy has the highest yield and tensile strength. This allows for much higher weight reductions while simultaneously elevating the protection level against projectiles especially AP projectiles. However, our heat treatment expertise enables a well-balanced mix of mechanical properties to achieve good ballistic resistance against FSP projectiles as well.Leveraging again our profound knowledge from the aircraft sector, we have successfully optimized stress corrosion cracking performance, which is a crucial factor, exceeding the required lifetime in laboratory testing by far. All these capabilities ensure that our 7020 plates consistently exceed the rigorous requirements of MIL-DTL-32505 across all the thickness ranges mentioned in the table above. Taking the superior welding performance of 7020 into account, AMAG ballistic plates from this alloy make the perfect choice for lightweight construction of highly agile ground vehicles. Here as well the plates can be delivered cut in specific contours as per customer’s request.

Development of 5083 plates with higher corrosion resistance and weldability

5083 alloy has been in demand for armor plates for a long time, especially due to its best-in-class weldability, superior corrosion resistance and superior blast protection – making it a definitive choice for marine armor plates and amphibious platforms. However, as a non-heat-treatable alloy, achieving the precise mechanical properties required for specific ballistic threats is a complex engineering challenge. Recent internal industrial trials show that meticulous adjustments to alloy chemistry and a carefully engineered thermomechanical process enables AMAG to tune the properties of 5083 in response to diverse projectile threats. The plates produced in these trials have shown to exceed the MIL-DTL-46027 specifications. These 5083 plates are particularly effective against Armor-Piercing (AP) projectiles, where they outperform standard requirements by a wide margin while maintaining their signature. Following positive results from these trials, AMAG is now transitioning to serial production of 5083 alloy plates to meet growing demand for armor plate solutions. The newly produced 5083 plates from the trials are currently at our customers for inspection.