When it comes to high-wear applications, standard steel just won’t cut it. That’s where abrasion-resistant (AR) plate comes in. AR400 and AR500 are two of the most popular grades, known for their hardness, durability, and resistance to wear and impact.
But what exactly makes AR400 and AR500 steel unique, and where are they used? In this blog, we’ll break down what AR plate is, how it’s made, and why industries rely on it for extreme conditions.
What Is Abrasion-Resistant (AR) Plate?
📌 Abrasion-resistant (AR) plate is a high-strength steel designed to withstand heavy wear, impact, and friction.
Unlike standard structural steel, AR plate is manufactured with a higher carbon content and special alloying elements, giving it exceptional hardness and toughness.
🔹 Key Features of AR Plate:
✔ Superior hardness – Resists scratches, dents, and gouges.
✔ High impact resistance – Withstands heavy loads and harsh conditions.
✔ Longer lifespan – Outlasts standard steel in abrasive environments.
✔ Heat-treated for extra strength – Quenched and tempered for durability.
💡 Think of AR steel like the armor on a tank—it’s built to take a beating without failing.
What Makes AR400 and AR500 Unique?
The numbers 400 and 500 in AR400 and AR500 refer to their Brinell Hardness Number (BHN), which measures resistance to indentation.
GradeBrinell Hardness (BHN)Best For
AR400360-440 BHNHeavy machinery, dump truck liners, buckets
AR500460-550 BHNBallistic armor, shooting targets, mining equipment
🔎 AR400 vs. AR500: Key Differences
✔ AR400 is softer and more impact-resistant, making it ideal for machinery that takes repeated hits.
✔ AR500 is harder and more wear-resistant, meaning it lasts longer but is more difficult to machine.
💡 Rule of Thumb: If impact resistance is the priority, choose AR400. If extreme wear resistance is needed, go with AR500.
How Is AR Plate Made?
📌 AR400 and AR500 undergo a special heat treatment process called “quenching and tempering” (Q&T), which increases hardness and strength.
🔎 Manufacturing Process:
1️⃣ Steel is heated to over 1,500°F (815°C) to change its molecular structure.
2️⃣ Quenching (Rapid Cooling) – The steel is quickly cooled with water or oil, making it extremely hard.
3️⃣ Tempering – The steel is reheated to reduce brittleness while maintaining toughness.
💡 This process creates a balance between hardness and toughness, preventing AR steel from being too brittle.
Common Applications of AR400 & AR500
📌 Abrasion-resistant plate is essential for industries that deal with heavy wear and impact.
IndustryCommon Uses
Mining & QuarryingConveyor belts, hoppers, rock crushers
Construction & Heavy EquipmentBulldozer blades, dump truck liners, excavator buckets
Shooting Ranges & BallisticsAR500 steel targets, body armor plates
AgriculturePlow blades, grain chutes, wear-resistant flooring
Recycling & Waste ManagementShredders, grinding equipment, landfill compactors
💡 Best Practice: AR500 is preferred in ballistic and impact applications, while AR400 is used in heavy machinery and industrial wear parts.
Challenges of Working with AR Plate
📌 While AR400 and AR500 offer superior hardness, they can be more challenging to cut, weld, and form.
🔹 Cutting:
✔ Plasma cutting or water jet cutting is preferred over traditional methods.
✔ Avoid excessive heat, which can reduce hardness.
🔹 Welding:
✔ Use low-hydrogen welding rods to prevent cracking.
✔ Preheat AR500 before welding to reduce stress.
🔹 Forming & Machining:
✔ AR500 is difficult to machine due to its high hardness.
✔ If bending is required, use AR400 instead of AR500.
💡 Pro Tip: Always follow manufacturer guidelines for processing AR steel to maintain its hardness and durability.
Final Thoughts: Why Choose AR400 or AR500?
📌 Abrasion-resistant (AR) plate is a game-changer for industries that require durable, long-lasting steel.
💡 Key Takeaways:
✅ AR400 is impact-resistant and ideal for machinery and heavy-duty wear parts.
✅ AR500 is harder and best for extreme wear applications like shooting targets and armor plating.
✅ Quenching and tempering make AR steel incredibly strong and resistant to abrasion.
✅ Proper cutting, welding, and forming techniques are essential to maintaining performance.
🚀 Need high-quality AR400 or AR500 for your project? Let’s talk!
