Military vehicles are commonly armoured to withstand the impact of shrapnel, bullets, shells, rockets, and missiles, protecting the personnel inside from enemy fire. Such vehicles include armoured fighting vehicles like tanks, aircraft, and ships. Armored vehicles represent a formidable fusion of technology and protection, standing as steadfast sentinels in the face of security challenges. From military battlefields to city streets, these robust machines play a vital role in safeguarding lives and assets.
Civilian vehicles may also be armoured. These vehicles include cars used by officials (e.g., presidential limousines), reporters and others in conflict zones or where violent crime is common. Civilian armoured cars are also routinely used by security firms to carry money or valuables to reduce the risk of highway robbery or the hijacking of the cargo.
Armour may also be used in vehicles to protect from threats other than a deliberate attack. Some spacecraft are equipped with specialised armour to protect them against impacts from micrometeoroids or fragments of space debris. Modern aircraft powered by jet engines usually have them fitted with a sort of armour in the form of an sort of bandage around the fan casing or debris containment walls built into the casing of their gas turbine engines to prevent injuries or airframe damage should the fan, compressor, or turbine blades break free.
The design and purpose of the vehicle determines the amount of armour plating carried, as the plating is often very heavy and excessive amounts of armour restrict mobility. In order to decrease this problem, some new materials (nanomaterials) and material compositions are being researched.
The protective capability of the laser welded armour steel plates
Despite the intensive development of plastics and composite materials in the case of armours employed to protect vehicles, armour steel remains a material commonly and effectively used. This is especially evident in the base armour of armoured vehicles, where the body is made of welded armour steel plates. However, the area of joining both the weld and the heat affected zone are sensitive areas with the reduced protective capability. In the case of laser welding in comparison with methods such as shielded metal arc welding and gas metal arc welding, it is possible to drastically narrow down the above capability areas with mentioned reduced protection.
Laser welding significantly improves the protective performance of joined armor steel plates compared to traditional fusion welding methods.
Key Findings on Protective Capability
Narrowed Heat-Affected Zone (HAZ): Traditional methods like shielded metal arc welding (SMAW) or gas metal arc welding (GMAW) create wide heat-affected zones and weld pools that weaken ballistic resistance. Laser welding minimizes the width of the weld and the HAZ, reducing ballistically vulnerable areas.
Hardness and Ballistic Performance: In laser-welded 500 HB armor steel plates (typically 4–5 mm thick):
Hardened weld regions can exceed 600 HV, which helps maintain or enhance ballistic stopping power against threats like 7.62 × 39 mm PS projectiles with mild steel cores.
The HAZ can experience a localized drop in hardness (sometimes falling below 400 HV due to tempering), which acts as a transition point that must be carefully managed through parameter optimization.
Penetration Resistance: Optimized laser welding parameters produce nearly defect-free joints. Ballistic tests confirm that laser-welded joints retain high penetration resistance comparable to unwelded base plates of the same thickness.
From Steel to Shield: The Crucial Role of Armor Plate and the welding of it!
Armor plates protect lives and critical assets from damage caused by high-velocity objects.
What is armor plate?
Armor steel plates are specially designed protective components used to shield against ballistic threats, impacts, and abrasions. These robust shields provide enhanced security in various industries, from defense and security to heavy machinery and transportation. These plates are commonly used in military transportation, body armor, armored vehicles, or infrastructure requiring enhanced security. Their purpose is to mitigate potential damage from attacks and to improve safety in high-risk scenarios.
What is armor plate made from?
Body armor plates can be created from ceramic, polyethylene, kevlar, or steel. Since it has to be carried by a person, body armor needs to be both light and effective. Armor plates for vehicles or buildings, however, can be made from heavier materials.
Primarily, armor plate is made from steel, specifically high-strength, hardened steel alloys that comply with military specifications. The specific steel alloys used in armor plates possess exceptional strength, toughness, and resistance to penetration. These alloys undergo rigorous manufacturing processes to achieve the desired protective properties.
Understanding military armor grades
Military armor plates are critical components of protective equipment used by military personnel and vehicles to mitigate the effects of projectiles, explosions, and other threats on the battlefield. These plates are designed to provide varying levels of resistance against different types of ammunition and combat scenarios. Among the armor grades used, MIL-A-46100 and MIL-A-12560 are two widely recognized specifications.
MIL-A 46100
MIL-A-46100 is a specification that defines the requirements for high-hardness armor plate designed to withstand ballistic threats. It is typically used for armored vehicles, including tanks and personnel carriers. This armor grade offers exceptional resistance against armor-piercing projectiles, such as those fired from heavy-caliber rifles and machine guns. MIL-A-46100 plates are made from high-hardness, low-alloy steel, which undergoes rigorous heat treatment processes to achieve the desired strength and toughness. This treatment enhances the plate’s ability to absorb and dissipate the energy generated by incoming projectiles, minimizing the chances of penetration.
MIL-A 12560
On the other hand, MIL-A-12560 is a specification that addresses the requirements for homogeneous armor plate designed for use in military vehicles and aircraft. This armor grade is more versatile compared to MIL-A-46100, as it provides protection against a wider range of threats, including ballistic, blast, and fragmentation hazards. MIL-A-12560 plates are made from a variety of materials, such as steel, aluminum, and composite laminates, depending on the desired characteristics and weight considerations. These plates undergo stringent testing to ensure they meet specific performance requirements, including hardness, tensile strength, and resistance to penetration.
Both MIL-A-46100 and MIL-A-12560 are subjected to rigorous testing procedures to evaluate their performance under various conditions. These tests involve shooting the armor plates with different ammunition types at specified velocities and angles to assess their resistance capabilities. Additionally, non-destructive testing techniques, such as ultrasonic inspection, are employed to detect any defects or inconsistencies in the plates’ structure.
Which military grade is right for me?
The choice between MIL-A-46100 and MIL-A-12560 depends on the intended application and the level of protection required. While MIL-A-46100 provides superior resistance against armor-piercing projectiles, MIL-A-12560 offers a more comprehensive defense against a wider range of threats. Consequently, MIL-A-46100 is often used in heavily armored vehicles where the primary concern is armor-piercing threats, while MIL-A-12560 finds applications in various military vehicles and aircraft that require a balance between protection and weight considerations.
Military armor plates play a crucial role in safeguarding military personnel and vehicles from ballistic and other threats on the battlefield. Grades such as MIL-A-46100 and MIL-A-12560 are designed to meet specific requirements and provide varying levels of protection. MIL-A-46100 excels in countering armor-piercing threats, while MIL-A-12560 offers a more versatile defense against a broader spectrum of hazards. The choice of armor grade depends on the intended application, the level of protection needed, and other factors like weight considerations.
Dimensions of armor steel
Armor steel plates are manufactured in various dimensions to cater to different applications and requirements. Commonly, these plates can range in thickness from less than 5 millimeters to 5/8ths of an inch, depending on the intended level of protection and the specific threat it aims to counter. Plates can be up to 580 inches long and 96 inches wide. The dimensions are carefully determined to balance weight, performance, and the required level of defense.
Companies transforming steel into armor
Various companies specialize in transforming military grade steel into steel armor plates. These companies possess the expertise, technology, and equipment necessary to shape, cut, and fabricate steel to meet the precise specifications required for armor applications. These processes often involve cutting, bending, welding, and heat treatment to achieve the desired final product.
What products does armor plate go into?
Armor plates find applications in a diverse range of products and industries. These include military and law enforcement vehicles, body armor for personnel, armored vehicles used in transportation and security, protective panels for buildings and infrastructure, and heavy machinery components subjected to high impact and abrasion.
Who certifies armor plates?
Certification plays a crucial role in ensuring the reliability and performance of armor plates. Independent testing agencies and organizations, such as the National Institute of Justice (NIJ) in the United States, conduct comprehensive tests to evaluate the ballistic resistance and effectiveness of armor plates. The certification confirms that the armor meets specific standards and provides the expected level of protection.
Armor plates rely on high-strength steel alloys, particularly military grades, to deliver reliable protection against ballistic threats and abrasion.
The careful selection of steel, precise dimensions, and the expertise of companies involved in their manufacturing are critical factors in producing effective armor plates.
With proper certification, armor plates provide an essential layer of safety in diverse applications, ensuring the protection of lives and critical assets in high-risk environments.
Rolled homogeneous armour is strong, hard and tough (does not shatter when struck with a fast, hard blow).
(does not shatter when struck with a fast, hard blow)
Steel with these characteristics is produced by processing cast steel billets of appropriate size and then rolling them into plates of required thickness. Rolling and forging (hammering the steel when it is red hot) irons out the grain structure in the steel, removing imperfections which would reduce the strength of the steel. Rolling also elongates the grain structure in the steel to form long lines, which enables the stress the steel is placed under when loaded to flow throughout the metal, and not be concentrated in one area.
Cast homogenous armour or cast steel armour is produced by directly casting steel into the desired shape. It tends to be softer as heat treatment is difficult or impossible. Nevertheless, the flexibility in shape has made it popular as the structural hull in modern tanks.
Aluminium
Aluminium is used when light weight is a necessity. It is most commonly used on APCs and armoured cars. While certainly not the strongest metal, it is cheap, lightweight, and tough enough that it can serve as easy armour.
Iron
Wrought iron was used on ironclad warships. Early European iron armour consisted of 10 to 12.5 cm of wrought iron backed by up to one metre of solid wood. It has since been replaced by steel due to steel being significantly stronger.
Titanium
Titanium has almost twice the density of aluminium, but can have a yield strength similar to high strength steels, giving it a high specific strength. It also has a high specific resilience and specific toughness. So, despite being more expensive, it finds an application in areas where weight is a concern, such as personal armour and military aviation.
Welding of High-Hardness Armor Steel
Armor steels are difficult to weld due to the high percentage of carbon.
The coarse-grained area and the fusion line in the normally welded joint are sensitive areas due to the high hardness and the possible presence of hydrogen produced during the welding process. Furthermore, multi-purpose armored vehicles made of armored steel are exposed to dynamic loading due to traffic on rough terrain. High hardness in the coarse- grained area of the heat-affected zone and dynamic loading can cause cracks. In the weld metal zone, a crack created during the welding process or due to pores can quickly propagate toward the sensitive fusion line, after which its accelerated growth can occur. Based on the above, achieving a welded joint without porosity or cracks for armor steel is necessary.
Laser welding is reducing this heat affected zone dratically and consequently minimize the eventual cracks or porosity at the welded zone8