What Is NM400 Steel?

In high-wear industries where machine components endure brutal friction and impact—like mining, quarrying, and construction—material failure isn’t an inconvenience; it’s a liability. That’s why professionals around the world are turning to NM400 steel, a wear-resistant plate that bridges cost-efficiency and high durability.

But how does it compare to global alternatives like Hardox 400? What’s its chemical composition, and does it meet global standards like ASTM? In this guide, we’ll break down everything—from specs and standards to nm400 vs hardox 400—so you can make informed choices backed by data and real-world insight.

NM400 at a Glance

NM400 steel is a wear-resistant alloyed steel plate that delivers excellent abrasion resistance and moderate impact strength. It’s widely used across dump truck bodies, earthmoving buckets, and mining wear parts.

What Does “NM400” Actually Stand For?

“NM” comes from the Chinese “Nai Mo” (耐磨), meaning “wear-resistant.” The designation tells you its specialty—endurance against friction and scraping in extreme environments. It’s a cornerstone in China’s domestic and export wear-resistant steel ecosystem.

The Meaning Behind the “400” in NM400

The “400” denotes its Brinell hardness number (HBW)—typically around 360–430. That places it right within the range of AR400-type steels, which are designed for heavy wear. This hardness makes NM400 equivalent in performance to certain Western brands like AR400 or Hardox 400, though each has unique features.

Understanding Wear-Resistant Steel

Not all steels are created to resist abrasion. Wear-resistant steels like NM400 are optimized to take a beating—literally.

What Makes a Steel Plate “Abrasion Resistant”?

Abrasion-resistant steels are designed for environments where surfaces constantly interact with rocks, sand, and other harsh media. Through alloying and heat treatment, plates like NM400 steel develop superior surface hardness, slowing down the wear process and increasing service life.

The Difference Between Hardness and Toughness

While hardness resists surface damage, toughness helps absorb impact without cracking. The advantage of NM400 material specification lies in balancing these two properties. It’s not just hard—it’s intelligently tough.

Chemical Composition of NM400

The strength of NM400 starts with its chemistry—a precise mix of alloying elements designed to harden the steel and reinforce its wear resistance.

A Breakdown of Elements Inside NM400

Element	Content (%)	Role
C (Carbon)	≤ 0.30	Increases hardness
Mn (Manganese)	≤ 1.60	Strengthens steel
Si (Silicon)	≤ 0.70	Supports deoxidation
Cr (Chromium)	≤ 1.20	Boosts wear resistance
Ni (Nickel)	≤ 0.70	Enhances ductility
Mo (Molybdenum)	≤ 0.50	Adds heat resistance
P + S	≤ 0.025	Controlled to reduce brittleness

How Chemistry Affects Wear Resistance and Strength

While the NM400 chemical composition focuses on durability under friction, the Hardox 400 chemical composition leans slightly more on impact resistance and uniformity—thanks to proprietary Swedish refining methods. However, both can be cut, welded, and processed with proper precautions.

Mechanical Properties That Matter

Engineers don’t buy steel—they buy performance numbers. Here’s what makes NM400 steel specifications competitive.

Brinell Hardness: Why 400 HBW Is the Sweet Spot

At 400 HBW, NM400 handles heavy abrasion while remaining weldable. It outperforms standard structural steels (like Q345) by lasting up to 5 times longer in high-wear applications.

Yield Strength, Tensile Strength & Impact Toughness

Property	NM400 Typical Value
Yield Strength	~900 MPa
Tensile Strength	~1250 MPa
Elongation	~12%
Impact Toughness	NM400:24J>-20°C(Thickness<80MM) NM400E: 24J>-40°C(Thickness<80MM)

These mechanical values align NM400 closely with Hardox 400 equivalent ASTM grades like AR400F.

Manufacturing Standards & Specifications

When purchasing steel, especially internationally, standard compliance matters as much as performance.

NM400 According to GB/T24186 Standard

NM400 material specification complies with GB/T24186, China’s standard for abrasion-resistant steels. It defines chemical limits, hardness ranges, and test methods. These specifications ensure consistency, especially for export buyers.

Thickness, Width, Length – Common Sizes Available

Parameter	Range
Thickness	2.0–150 mm
Width	1250–3500 mm
Length	5000–12000 mm

These standard dimensions allow seamless integration into manufacturing pipelines worldwide.

How NM400 Compares to Other Grades

Let’s break down the real-world difference between NM400 and its global counterparts.

NM400 vs Hardox 400: The Classic Face-Off

Hardox 400 is a premium brand by SSAB, known for tight tolerances and extreme flatness. But NM400 offers equivalent wear resistance, broader availability in Asia, and a significantly better cost-benefit ratio—ideal for mid-budget operations.

NM400 vs NM500: When Do You Need More Hardness?

NM500 boosts hardness to ~500 HBW but sacrifices ductility and weldability. NM400 is more forgiving for fabrication-heavy projects.

NM400 vs AR400 / Hardox 400 Equivalent Material

In terms of hardox 400 equivalent material, NM400 steel equivalent grades include AR400F, BISPLATE 400, and XAR400, depending on region. However, NM400 is often preferred in regions like Southeast Asia for its balance of cost and versatility.

Applications of NM400 Steel

From mine pits to urban job sites, NM400 steel is everywhere.

Industries That Rely on NM400

Mining & Excavation
Cement & Aggregate Plants
Earthmoving Equipment
Steel Recycling & Scrap Handling
Agricultural Wear Tools

Common Components Made with NM400 Steel

Dump truck liners
Crusher and hopper walls
Bulldozer blades
Excavator bucket teeth
Conveyor chute panels

Real-World Use Case

A coal transport company in Indonesia switched from Q345 to NM400 and saw liner service life jump from 4 months to 15—with reduced maintenance and fewer shutdowns.

Processing & Fabrication Insights

High-performance doesn’t mean high-difficulty—if you follow best practices.

Can NM400 Be Cut, Bent, and Welded Easily?

Yes. NM400 can be cut using plasma, laser, or oxy-fuel. Cold bending is possible with large inner radii. Weldability is good, provided preheating and correct filler materials are used.

Best Practices for Welding NM400 Without Cracks

Preheat to 150–200°C
Use E7018 or equivalent low-hydrogen rods
Post-weld stress-relieving optional for thick plates
Cool slowly to avoid heat-affected zone cracking

Machining Tips

Use carbide tools, reduce spindle speeds, and maintain constant coolant flow. Surface finish may require grinding due to the hardness.

Surface Treatment & Finishing Options

Durability improves even more with proper protection.

Does NM400 Need Additional Coating?

Yes. Like many AR steels, NM400 is not corrosion-resistant. It must be coated in marine, coastal, or acidic environments.

Painting, Powder Coating, and Galvanizing Compatibility

NM400 takes coatings well—especially after abrasive blasting. Powder coating, zinc-rich primers, or epoxy systems greatly enhance outdoor performance.

Pros and Cons of NM400 Steel

Let’s lay it all out.

The Strengths That Make It Popular

Competitive with Hardox 400 equivalent materials
High availability in Asia and global trade hubs
Weldable and machinable
Cost-effective for medium to heavy abrasion

Limitations You Should Know

Requires controlled welding conditions
Not suitable for ultra-high-impact jobs (choose NM500 or Hardox 450+)
Corrosion resistance must be added externally

Have advantages in the manufacture of thin wear-resistant steel

With excellent steelmaking and heat treatment capabilities, can produce wear-resistant steel with a width of 3000MM

Sourcing NM400: Global Availability

Material is only as good as your ability to source it reliably and on time. NM400 steel excels here too.

Where NM400 Is Produced and Exported From

Most NM400 production comes from China’s steel giants such as Baosteel, Angang, Shenglon, and Valin . These mills offer high-volume output, standardized quality, and competitive pricing. NM400 is now widely exported to:

Southeast Asia
Middle East
Africa
Eastern Europe
South America

Key Chinese Manufacturers and Mill Brands

Mill Name	Strengths
Baosteel	High flatness, tight specs
Angang	With excellent steelmaking and heat treatment capabilities, can produce wear-resistant steel with a width of 3000MM
Shenglong/VALIN	Have advantages in the manufacture of thin wear-resistant steel
Wuyang,WISCO,Xinyu ETC	Every steel mill has its own unique advantages

Different from other countries, there are thousands of steel mills manufacturing various steels in China. So, it’s hard to tell in details. They all have their own unique advantages. Except contacting with steel mill directly, find a professional service company would help you get your suitable products easily while purchasing wear-resistant steel.

Price and Value Breakdown

Let’s talk ROI.

Average Cost Per Ton of NM400 Steel

Thickness	Price Range (USD/ton)
6–12 mm	$750 – $850
14–25 mm	$800 – $900
30+ mm	$850 – $950

Prices depend on coil vs plate, origin, thickness, surface finish, and quantity. Compared to Hardox 400, NM400 is often 30–40% more cost-effective.

Is It Worth the Investment?

Yes. Many clients using nm400 steel equivalent in performance to Hardox 400 save thousands annually in material cost, logistics, and replacement cycles. For moderate-to-heavy abrasion, it hits the sweet spot of cost, lifespan, and workability.

Sustainability and Recycling

Durability and eco-friendliness don’t have to be at odds.

Is NM400 Eco-Friendly?

Absolutely. NM400 is:

Fully recyclable
Manufactured under low-emission EAF routes (by major mills)
Reusable in secondary applications after wear

How to Recycle or Repurpose NM400 Steel Parts

Melt into rebar or construction steel
Repurpose worn liners into farm tools or fencing
Use as ballast or support plates in non-wear applications

Steel that lasts longer also gets replaced less—cutting carbon by reducing logistics and rework.

Frequently Asked Questions About NM400

Let’s answer the most common buyer and engineer queries:

Is NM400 a Type of Alloy Steel?

Yes. It is a low-alloy wear-resistant steel enhanced with chromium, manganese, and molybdenum. It is not a stainless steel, but a structural AR-grade.

Can NM400 Be Used for High-Impact Parts?

Yes—for moderate to high impact. For ultra-high impact zones like hammer crushers, NM500 or Hardox 450/500 may offer better fracture resistance.

What’s the Shelf Life of NM400 in Harsh Environments?

With coating: 10+ years.
Without coating: up to 3–5 years depending on climate and wear conditions.

It’s recommended to apply corrosion protection if exposed to moisture or chemicals.

Final Thoughts

NM400 steel is not just an alternative—it’s a global-grade workhorse.

When NM400 Is the Right Choice

Moderate to heavy wear environments
Projects needing weldability + hardness
Fabricators working with standard processing tools
Operators needing long wear life without premium pricing

For 70% of wear-resistant applications, NM400 offers Hardox-level performance at significantly better cost and availability.

Questions to Ask Your Supplier Before Buying

Is the steel GB/T24186 certified?
What’s the exact Brinell hardness?
Can you provide MTCs (mill test certificates)?
Do you recommend preheating for welding?
What surface finish is provided?

By asking these questions, you ensure you’re sourcing genuine, high-grade NM400 material, not off-brand substitutes.

Summary: Why NM400 Works

NM400 steel has proven its worth across continents. It is:

Reliable
Wear-resistant
Cost-effective
Process-friendly
Globally available

Whether you’re seeking a Hardox 400 equivalent ASTM-grade material or simply looking to improve uptime in a high-abrasion setting, NM400 delivers measurable ROI.

It’s not hype. It’s just smart steel.