Armoured fighting vehicles (AFVs) are engineered to endure the extremes of modern warfare. They are expected to move quickly, protect their crew, and operate reliably under fire. Sensors and weapons are essential to their function, but without the right structural foundation, these systems cannot perform at their best. Steel forms the backbone of these vehicles, shaping how they respond to impact and perform in demanding environments. The choice of steel grade directly affects how well a vehicle balances protection, mobility, and durability.
The Role of Steel in Armoured Vehicle Design
Steel is central to AFV design, not simply as a structural component but as an active part of the vehicle’s protection system. Different parts of an armoured vehicle are exposed to distinct threats:
- High-hardness steels counter direct ballistic impact on exterior surfaces
- High-strength steels provide support where structural loads are concentrated
- Blast-resistant steels mitigate damage from underbody explosive forces.
This multifaceted role requires a portfolio of steel types, each engineered for specific threat profiles and mobility needs. A well-chosen combination of steels can mean the difference between a vehicle that merely endures and one that performs with precision in modern combat.
Armour Steel Grades for Modern AFVs
Protection 500
Engineered for high-risk combat zones and urban conflict areas, Protection 500 features a hardness range of 480 to 540 Brinell and a yield strength of 1250 MPa. This grade introduces a significant improvement in ballistic resistance without an equivalent rise in thickness.
Why it suits modern AFVs
Vehicles that operate in high-threat theatres benefit from the elevated hardness of Protection 500. The material’s ability to absorb and deflect kinetic energy helps safeguard critical zones like turrets and forward-facing panels.
Advantages
- Enhances resistance to high-velocity, armour-piercing threats
- Maintains durability without adding excessive weight
Applications in AFVs
- Turret faces and frontal hull plates under heavy fire
- Bolt-on panels designed for field upgrades
- Armour layers requiring a balance of weight and protection
MIL-DTL-12560
As one of the most trusted names in military-grade armour, MIL-DTL-12560 combines hardness, shock resistance, and formability. Manufactured to a well-established U.S. defence specification, MIL-DTL-12560 ensures dependable performance across a broad threat spectrum.
Why it suits modern AFVs
Used extensively across generations of armoured platforms, MIL-DTL-12560 remains a dependable option for both legacy upgrades and new builds. Its combination of strength and versatility supports mission profiles ranging from urban patrols to high-intensity combat operations, where adaptable and durable protection is crucial.
Advantages
- Provides consistent ballistic resistance and structural integrity
- Offers versatility across a wide range of vehicle configurations
Applications in AFVs
- Main hulls and roof panels for armoured transport vehicles
- Retrofit programmes extending the lifespan of older fleets
- Base layers in composite or modular armour designs
S690QL
S690QL is a high-strength structural steel with a minimum yield strength of 690 MPa. Known for durability under mechanical stress and reliable toughness at low temperatures, S690QL serves well where weight must be trimmed without compromising integrity.
Why it suits modern AFVs
S690QL is commonly used where reduced vehicle weight is a priority. The dependable performance of this steel allows designers to preserve strength while improving speed and handling.
Advantages
- Allows for thinner structural components with its high yield strength
- Ensures mechanical performance in cold environments
Applications in AFVs
- Lightweight chassis and frame structures
- Support mounts for modular systems and internal components
- Mobility-focused vehicles requiring structural strength
S960QL
Delivering a yield strength of 960 MPa, S960QL ranks among the highest-performing structural steels used in AFV production. The material offers exceptional load-bearing capability and integrates smoothly into advanced armour systems.
Why it suits modern AFVs
S960QL is frequently applied in areas requiring both rigidity and resilience. This steel provides structural support without imposing weight penalties, which is especially valuable in fast-moving, high-mobility vehicles.
Advantages
- Establishes agile vehicle design with high strength-to-weight performance
- Provides reliable toughness during high-impact operations
Applications in AFVs
- Structural reinforcements in high-speed vehicles
- Armour backing and load-bearing substructures
- Lightweight hull designs prioritising tactical manoeuvrability
440T
Designed for upper-tier ballistic demands, 440T delivers higher hardness and tensile strength for components under repeated direct attack. Its role in AFVs is often at the outermost edge of protection, where split-second resistance can mean survival.
Why it suits modern AFVs
High surface hardness and tensile strength make 440T ideal for modular armour designs regularly exposed to intense combat scenarios. Commonly integrated into outer layers, the grade supports layered and bolted-on protection with dependable resilience.
Advantages
- Withstands high-velocity impacts and direct fire threats
- Sustains durability under prolonged exposure to combat conditions
Applications in AFVs
- Outer skins and protective cladding on combat vehicles
- Removable armour plates for mission-specific adjustments
- Panels reinforcing turrets and exposed weapon stations
Turning Steel into Capability
Steel selection shapes how armoured vehicles perform in demanding environments. It influences how they traverse terrain, absorb impact, and respond to evolving threats. Each grade contributes to a careful mix of mobility, protection, and reliability. Achieving that combination requires more than specifications. It calls for materials that deliver proven performance. Masteel provides steels developed for these challenges. To explore the options available, get in touch and discover how the right steel grade can support your next defence project.