What are the differences between NM500 and AR500?
When purchasing wear-resistant steel plates for mining, construction, or material handling, many buyers confuse NM500 and AR500. Both are widely used, but their differences in composition, hardness, wear resistance, and application scenarios are significant. Choosing the wrong type can shorten service life and increase costs. This article simplifies their core differences to help you select the right material.
What is NM500?
NM500 is a domestically produced high-strength wear-resistant steel plate. "NM" stands for "wear-resistant" in pinyin, and "500" indicates its Brinell hardness is approximately 500 HBW (actually 480–525 HBW). It is typically delivered in a quenched and tempered state. Its wear resistance is 3–5 times that of ordinary steel plates. It is widely used in high-wear components such as excavator buckets, crusher liners, mine chutes, and dump truck floor plates, significantly extending equipment life and reducing maintenance costs.
What is AR500?
AR500 wear-resistant steel plate is a high-hardness (typical hardness 477-550 HBW) and high-strength wear-resistant steel plate. With its excellent resistance to sliding wear and impact, it is widely used in heavy-duty applications such as mining, excavation, loader buckets, crushers, and conveyor troughs. It can significantly extend equipment service life and reduce downtime for replacements.
| C | P | S | |||||||
|---|---|---|---|---|---|---|---|---|---|
| AR500 | 0.25-0.35 | 0.20-0.80 | 0.70-1.20 | <=0.025 | <=0.010 | 0.50-1.50 | 0.20-0.50 | <=0.50 | 0.0005-0.005 |
| NM500 | <=0.38 | <=0.70 | <=1.70 | <=0.020 | <=0.010 | <=1.50 | <=0.65 | <=1.00 | 0.0005-0.006 |
AR500
AR500 wear-resistant steel plates utilize a low-alloy composition system, with carbon content typically controlled at around 0.25%–0.35%, chromium at approximately 0.50%–1.50%, molybdenum at approximately 0.20%–0.50%, and trace amounts of boron (<=0.005%) to enhance hardenability. The high-carbon, chromium-molybdenum composite alloy design results in a higher pre-hardened surface hardness (477–534 HBW), making it particularly suitable for purely abrasive conditions. However, the manganese content is relatively low, and the carbon equivalent is high, requiring preheating and slow cooling processes during welding and cold forming. Corrosion resistance is generally average, but in media containing trace amounts of acid, the chromium content provides a certain boost to wear resistance.
NM500
NM500 is a high-hardness wear-resistant steel plate. To achieve higher hardness and wear resistance, the content of alloying elements has been significantly increased. The addition of trace amounts of boron (0.0005%–0.006%) further enhances hardenability. Due to the increased total alloy content, the carbon equivalent (CEV) of NM500 rises to approximately 0.65, meaning that it is much more difficult to weld and machine than NM400.
Both have similar Brinell hardness (NM500: 480-520 HBW; AR500: 470-530 HBW), but NM500 has better uniformity. NM500's Cr and Mo content makes its wear resistance 1.2-1.5 times that of AR500 in heavy-wear scenarios, while AR500 suffices for medium-wear environments.
AR500
NM500 has higher impact toughness (>=20 J/cm²) and better processability (preheating 150-200℃ for welding).
AR500 has lower toughness (>=15 J/cm²) and requires higher preheating (200-250℃), with higher processing difficulty.
AR500
AR500 wear-resistant steel plates are primarily used in heavily worn parts of mining and construction machinery: excavator/loader bucket bottom plates and side edges, dump truck bed liners, crusher and chute linings, hopper and conveyor baffles. They can significantly extend the lifespan of critical components, reduce equipment downtime for replacements, and allow for weight-saving designs, thereby significantly improving overall operational efficiency in heavy-duty conditions.
NM500
The NM500 is suitable for harsh working conditions with severe wear and tear. For example, crusher liners, large mining car bodies, ore hoppers, wear-resistant parts for heavy excavators, sintering equipment liners, and high-hardness rock conveying equipment. It is suitable for hard ores, granite, and high-intensity impact and wear scenarios.
Cost Of NM500 vS AR500
While performance is nearly identical, the biggest difference between NM500 and AR500 lies in cost.
| AR500 Steel | NM500 Steel | |
|---|---|---|
| 30%–40% lower | ||
In practical terms, choosing NM500 allows buyers to achieve the same functional performance while significantly reducing material costs. For large-scale projects, this difference can have a major impact on the total budget.
In what situations should you choose the NM500 instead of the AR500?
When there are higher requirements for impact toughness, low-temperature service reliability, and welding/cold forming friendliness, NM500 should be preferred over AR500.
The NM500 should be preferred in the following four situations:
High-impact conditions: When equipment needs to withstand repeated impacts and strong vibrations from large pieces of ore and rock, the superior ductility and impact toughness of the NM500 significantly reduce the risk of brittle fracture. Typical components such as crusher liners and coal mining machine chutes are suitable for this scenario.
Low-temperature environment operation: When equipment operates in northern winters, high-altitude areas, or even frigid regions, the NM500 (especially the NM500D/E grade) can stably meet the impact resistance requirements at temperatures ranging from -20℃ to -40℃. In contrast, the standard AR500 is not specifically designed for low-temperature applications and poses a risk of low-temperature brittle fracture.
Complex manufacturing and repair needs: For applications requiring extensive welding, bending, or subsequent on-site welding repair, the relatively low carbon equivalent of the NM500 provides superior weldability and cold-working operability, reducing preheating and post-weld processing costs.
Cost and supply considerations: NM500 complies with the Chinese national standard GB/T24186, has a wider domestic supply network and a more mature pricing system, making it more competitive in terms of overall cost, especially for bulk purchases. AR500, on the other hand, mostly follows ASTM standards, and its supply chain is relatively concentrated.
If your project does not require specific regional certifications associated with AR500, then switching to NM500 steel plates would be a strategic decision that balances performance and cost.
If you are looking for a cost-effective alternative with performance comparable to AR500, NM500 abrasion-resistant steel plates are a proven and ideal choice.
Consistently high-quality NM500 steel plates
Contact us today for a highly competitive quote and reduce your project costs by using NM500 steel plates.
1. What is the difference between AR500 and NM500?
AR500: Higher carbon (C: ~0.38–0.45%), chromium (Cr: ~1.5%), and boron (B: 0.0005–0.006%) for enhanced hardness and corrosion resistance . NM500: Lower carbon (C: <=0.38%), added nickel (Ni: <=1.0%) and molybdenum (Mo: <=0.65%) for balanced weldability and toughness.
2. How should wear-resistant steel plates be cut?
Wear plates can be processed by either flame cutting or plasma cutting. Particularly for NM500, preheating before cutting and slow cooling after cutting are mandatory to avoid delayed cracking.
3. Can NM500 be welded?
NM500 is weldable but demands strict welding procedures. It needs preheating at 100–150℃, matched low-hydrogen welding materials, and proper post-weld tempering treatment to guarantee welding quality.
4. Which is stronger, AR500 or AR550?
AR550 steel is harder than AR500, offering superior resistance to pitting and cratering. That extra ~50 BHN makes a noticeable difference, especially with high-velocity rounds.