Wear-resistant Steel Plate
Wear Resistant Steel Plate Supplier – NM400, NM450, NM500 & NM600
LYH Steel supplies wear-resistant steel plate for mining, construction machinery, material handling, cement, power and other abrasion-intensive equipment.
Chinese NM grades are classified primarily by their nominal Brinell hardness level. A higher NM number generally provides greater abrasion resistance, but also increases the importance of cutting, welding, bending, machining and impact-service evaluation.
NM Wear Resistant Steel Plate: Quick Selection
Common starting point where abrasion resistance and fabrication flexibility both matter.
Higher wear resistance while retaining useful fabrication capability for many equipment parts.
Used where stronger abrasive-wear resistance is required and fabrication can be more controlled.
Very high hardness for severe abrasion applications; fabrication feasibility needs careful review.
NM400 vs NM450 vs NM500 vs NM600 Hardness
Under GB/T 24186-2022, the NM designation reflects the nominal surface Brinell hardness class. Actual acceptance ranges depend on grade and plate thickness.
| Grade | Thickness | Surface Brinell Hardness | Selection Note |
|---|---|---|---|
| NM400 | ≤ 80 mm | 370–430 HBW | Balanced abrasion resistance and fabrication |
| NM400 | >80–120 mm | 360–440 HBW | Heavy plate range under the standard |
| NM450 | ≤ 80 mm | 420–480 HBW | Higher wear resistance than NM400 |
| NM450 | >80–120 mm | 410–480 HBW | Heavy plate range under the standard |
| NM500 | ≤ 70 mm | 470–540 HBW | High abrasion resistance |
| NM500 | >70–100 mm | 450–540 HBW | Fabrication requires increasing control |
| NM600 | ≤ 60 mm | 570–640 HBW | Very high abrasion resistance; fabrication review required |
GB/T 24186-2022 Wear-Resistant Steel Standard
GB/T 24186-2022 is the Chinese national standard for high-strength abrasion-resistant steel plate, sheet and strip for engineering machinery.
The standard addresses subjects including grade designation, order information, dimensions, technical requirements, testing, inspection, marking and certification.
What “NM” Means
“NM” is derived from the Chinese term for wear resistance, nai mo.
The number identifies the nominal surface Brinell hardness class, such as NM400 or NM500.
D / E Quality Variants
NM grades may also be supplied in low-temperature toughness variants where specified by the applicable standard and purchase contract.
Buyers should specify the exact grade suffix rather than simply requesting “NM450 wear plate.”
Abrasion vs Impact: How to Choose the Right NM Grade
Wear plate selection should start with the actual wear mechanism. Hardness alone does not describe the whole application.
| Service Condition | Grade Direction to Evaluate | Main Engineering Question |
|---|---|---|
| Moderate abrasion + significant fabrication | NM400 / NM450 | Can service life improve without making fabrication unnecessarily difficult? |
| Abrasion + repeated impact | NM400 / NM450 / suitable toughness variant | Does the plate retain sufficient impact performance? |
| Heavy sliding abrasion | NM450 / NM500 | Is wear rate more important than forming complexity? |
| Severe abrasion with limited forming | NM500 / NM600 | Can the component be cut, welded and machined reliably? |
| Low-temperature impact service | Specified toughness-grade NM material | What impact temperature and energy are contractually required? |
Cutting NM400–NM600 Wear Plate
Wear-resistant steel can be cut, but higher hardness and thicker plate increase sensitivity to cut-edge cracking, heat-affected-zone softening and distortion.
Plasma Cutting
Commonly used for wear plate. Gas selection, plate temperature, thickness and cutting parameters should follow the mill and cutting-equipment recommendations.
Oxy-Fuel Cutting
Practical for many plate thicknesses, but some combinations of hardness and thickness may require preheating or other crack-control measures.
Laser Cutting
Suitable for selected plate thicknesses and equipment capabilities. Do not automatically apply oxy-fuel preheat recommendations to laser cutting.
Welding Wear-Resistant Steel Plate
NM wear plate can be welded, but calling NM400–NM600 simply “easy to weld” is not sufficiently precise.
The main concern is controlling hydrogen-assisted cold cracking while limiting unnecessary softening of the heat-affected zone.
| Welding Variable | Why It Matters |
|---|---|
| Grade | Higher hardness normally increases fabrication sensitivity |
| Plate Thickness | Thicker sections can require higher preheat / heat control |
| CEV / CET | Helps assess hardenability and welding crack risk |
| Hydrogen Level | Low-hydrogen practice helps reduce cold-cracking risk |
| Heat Input | Too much heat can soften the HAZ; too little can increase cooling rate |
| Preheat / Interpass Temperature | Must follow grade, thickness and welding procedure |
| Joint Restraint | High restraint increases residual stress and cracking risk |
Procurement recommendation: obtain the actual MTC chemistry and mill fabrication guideline before approving the welding procedure. For critical fabrication, preheat, heat input, consumables and interpass temperature should be defined by the WPS.
Bending & Cold Forming
Wear plate is not ordinary mild steel. As hardness increases, minimum bend radius, springback and risk of cracking become increasingly important.
NM400 / NM450
Often selected where abrasion resistance must be combined with significant fabrication, but the permitted bend radius must still follow mill-specific recommendations.
NM500 / NM600
Higher hardness means bending feasibility needs more careful assessment. NM600 should not be described generically as “easy to bend.”
Machining & Drilling NM Wear Plate
Wear-resistant steel is machinable, but tool load, tool wear and cutting parameters increase with hardness.
Drilling and machining plans should consider:
- actual HBW hardness,
- machine rigidity,
- tool material and geometry,
- cutting speed and feed,
- coolant strategy,
- hole diameter and depth,
- plate thickness.
NM400 vs Hardox 400, XAR 400 & Other Wear Plates
NM400, Hardox 400, XAR 400, durostat 400 and other 400-class plates may occupy a similar nominal hardness category, but they can differ in:
- chemical composition,
- hardness guarantee and measurement position,
- impact toughness,
- through-thickness hardness,
- flatness and thickness tolerance,
- bendability guarantees,
- welding recommendations,
- available thickness range.
The same applies to 450, 500 and 600 hardness classes. A branded wear plate should only be replaced after the project specification and required properties have been compared.
Wear Resistant Steel Plate Applications
Mining
Crusher liners, screens, chutes, buckets, hoppers and material-transfer components.
Construction Machinery
Excavator buckets, loader components, bulldozer wear parts and dump-body liners.
Cement & Aggregate
Mixer liners, crusher components, chutes, transfer points and abrasive-material handling systems.
Coal & Power
Coal hoppers, mill liners, conveying components and wear-prone handling equipment.
Metallurgical Equipment
Sintering equipment, liners, scraper components and abrasive-material transport systems.
Port & Bulk Handling
Grab components, hopper liners, chute liners and bulk-material handling equipment.
NM400–NM600 Application Guide
| Grade | Typical Direction | Fabrication Consideration |
|---|---|---|
| NM400 | Buckets, liners, moderate abrasive wear, general wear parts | Useful when welding / forming requirements remain important |
| NM450 | Higher-wear buckets, liners, dump bodies and handling equipment | Balances increased hardness with practical fabrication |
| NM500 | Heavy abrasion, mining, crushers, chutes and severe wear parts | Cutting, drilling, bending and welding need tighter control |
| NM600 | Very severe abrasion where high hardness dominates the design | Use only after fabrication and impact requirements are confirmed |
Wear Plate Inspection & Material Verification
For NM wear plate, hardness and material identity should be traceable to the supplied heat and purchase specification.
| Inspection Item | Purpose |
|---|---|
| MTC / Mill Certificate | Verify grade, chemistry, heat number and reported test results |
| Brinell Hardness | Confirm compliance with specified hardness range where required |
| Thickness / Dimensions | Confirm ordered plate dimensions and tolerances |
| Surface / Flatness | Check handling, processing and fabrication suitability |
| Impact Test | Required when a specified low-temperature toughness grade calls for it |
| UT | Specify when internal quality examination is contractually required |
| Third-Party Inspection | Available when required by PO / project specification |
Related service: Quality Inspection .
Wear Resistant Steel Plate RFQ Checklist
For an accurate quotation, do not send only “NM500 plate price.” Include the actual engineering and fabrication requirements.
- Grade: NM400, NM450, NM500, NM600 or specified toughness variant.
- Standard: GB/T 24186-2022 or project-specific requirement.
- Thickness: required plate thickness.
- Width and length: finished plate dimensions.
- Quantity: pieces or total metric tons.
- Application: bucket, liner, chute, crusher, dump body or other component.
- Wear condition: sliding abrasion, impact + abrasion, mineral type or other service details.
- Temperature: ambient, low-temperature or elevated-temperature operation.
- Processing: cutting, drilling, bending, welding or prefabrication if required.
- Inspection: hardness test, MTC, UT or third-party inspection where required.
- Documentation: certification and traceability requirements.
- Destination: port, packing and Incoterm.
Related Steel Plate & Procurement Resources
Technical Reference Notes
GB/T 24186-2022
Chinese national standard for high-strength abrasion-resistant steel plate, sheet and strip used in engineering machinery.
Welding Guidance
Wear-plate welding requires control of hydrogen, heat input, preheat / interpass temperature and joint restraint.
Cutting Guidance
Thermal-cutting recommendations depend on grade, thickness and cutting method.
Wear Resistant Steel Plate FAQ
1. What is wear-resistant steel plate?
Wear-resistant steel plate is engineered to provide high surface hardness and resistance to abrasive wear in equipment such as buckets, liners, chutes, crushers and dump bodies.
2. What does NM400 mean?
NM identifies a Chinese wear-resistant steel family, while 400 refers to its nominal surface Brinell hardness class. Actual acceptance limits depend on the applicable standard and thickness.
3. What is the difference between NM400 and NM500?
NM500 has a higher hardness class and is generally selected where greater abrasion resistance is required. NM400 can be more practical where extensive forming, welding or impact performance is an important part of the application.
4. Is NM600 better than NM500?
Not for every application. NM600 provides higher hardness, but fabrication, impact loading, machining, welding and bending requirements may make NM500 or a lower hardness grade more suitable.
5. Can NM600 be cut?
Yes, but cutting procedure should follow the actual grade, thickness, cutting method and mill recommendation. Preheating is not a universal requirement for every cutting process.
6. Can NM600 be welded?
Yes, when an appropriate welding procedure is used. Preheat, low-hydrogen consumables, heat input, interpass temperature and joint restraint may all need control.
7. Can NM600 be bent?
Bending feasibility must be confirmed for the actual product. High hardness significantly affects bendability, required bend radius and cracking risk, so NM600 should not be treated like conventional mild steel.
8. Is NM400 the same as Hardox 400?
No automatic equivalence should be assumed. The products may have similar nominal hardness, but standard, chemistry, toughness, hardness guarantee, tolerances and fabrication recommendations may differ.
9. Which grade should I use for mining equipment?
It depends on abrasion severity, impact loading, component geometry, required service life and fabrication. NM450 or NM500 are common directions to evaluate for many mining wear parts, but final selection is application-specific.
10. What should I include in a wear-plate RFQ?
Include grade, standard, thickness, width, length, quantity, application, abrasion / impact conditions, required processing, inspection, destination and any low-temperature toughness requirement.
Select Wear Plate by Wear Mechanism—not Hardness Alone
Moving from NM400 to NM450, NM500 or NM600 can increase abrasion resistance, but higher hardness also changes the fabrication envelope.
The correct procurement comparison is: hardness + abrasion + impact + thickness + cutting + welding + bending + machining + inspection.