Huaxia-Steel supplies NM400 wear resistant steel plate — a quenched (and optionally tempered) Chinese-standard wear plate with a surface hardness of 360–430 HBW, engineered for mining equipment, crusher liners, dump truck bodies and earthmoving wear parts. Compared with ordinary structural plate like Q355, NM400 delivers 3–4 times longer service life in sliding abrasion, and it still machines, bends and welds with standard workshop practice. We stock 6–80 mm thickness and cut to your drawings by plasma, oxygen or laser, with flatness and DCE (decarb-free edge) options.
Product Overview
NM400 belongs to the GB/T 24186 family of high-strength wear-resistant steels (NM = 耐磨, “wear resistant”; 400 = nominal Brinell hardness). It is produced by quenching low-alloy steel with controlled carbon, chromium, molybdenum and boron to form a martensitic microstructure — the source of its hardness. International equivalents you may already be buying:
| China | Hardox (SSAB) | JFE | Dillinger | Typical Hardness |
|---|---|---|---|---|
| NM400 | HB400 | JFE-EH400 | Dillidur 400 | 360–430 HBW |
Availability summary:
- Thickness: 6–80 mm; width: up to 3,350 mm; length: up to 16,000 mm.
- Delivery condition: quenched (Q) or quenched + tempered (QT) per thickness.
- Grades in family: NM360, NM400, NM450, NM500, NM550 — we quote the hardness/life balance your application needs.
Specifications & Mechanical Properties
| Property | NM400 (t ≤ 30 mm) | NM400 (30 < t ≤ 80 mm) |
|---|---|---|
| Surface hardness | 360–430 HBW | 360–430 HBW |
| Min. yield Rp0.2 | ≥1,000 MPa | ≥950 MPa |
| Tensile Rm | ≥1,200 MPa | ≥1,150 MPa |
| Elongation A50 | ≥10% | ≥9% |
| Charpy (0 °C, 0.5×t) | ≥24 J (transverse) | ≥21 J |
Chemical Composition (typical, %)
| C | Si | Mn | P | S | Cr | Mo | B |
|---|---|---|---|---|---|---|---|
| ≤0.30 | ≤0.70 | ≤1.60 | ≤0.025 | ≤0.010 | ≤1.20 | ≤0.50 | 0.001–0.004 |
Low sulfur (≤0.010%) and controlled boron are what separate genuine NM400 from re-rolled “wear plate” sold by weight — always demand the ladle analysis and hardness reports.
Fabrication Guidelines
- Cutting: plasma, laser and oxygen cutting all work. For thickness ≥ 20 mm, preheat cut edges to 100–150 °C to avoid edge cracking; slow cooling for heavy sections.
- Bending: minimum bend radius ≈ 3.5–4 × t with the bend axis transverse to rolling direction; die opening ≈ 8–10 × t. Bending must be done promptly (within days of cutting) at moderate speed.
- Welding: low-hydrogen electrodes (E7018 class or matching hardfacing wires); preheat 100–150 °C for t ≥ 20 mm; keep interpass ≤ 200 °C. The low CEV design keeps procedures simple.
- Machining: carbide tooling, low surface speed — it is a wear plate, not a free-cutting steel.
Applications
- Dump truck bodies, tipper liners, trailer floors and side walls.
- Crusher jaws, hopper liners, chutes, feeders and screen plates in mining and aggregate plants.
- Excavator buckets, loader bucket liners, bulldozer blade edges and wear pads.
- Cement, steel and port handling equipment: conveyor skirting, bunker linings, scraper blades.
Grade selection tip: for sliding abrasion with impact (rock on plate), NM400–NM450 is the sweet spot; for pure sliding of fine abrasive material, NM500/NM550 extends life; where forming is severe, step down to NM360 to avoid cracking.
Quality Assurance
- Hardness verification: Brinell survey across each plate (edges, center, quarter points) — report included with shipment.
- Tensile and Charpy tests per GB/T 24186 or ASTM A514-equivalent practice, heat-by-heat, with EN 10204 3.1 certificates.
- UT soundness per GB/T 2970 / ASTM A578 on heavy thicknesses.
- Flatness control: ≤10 mm/m typical after quench; we re-straighten or supply DCE plates for precision liners.
- Cutting accuracy: plasma ±1.0 mm, laser ±0.3 mm, with dimension reports on finished parts.
Packaging & Shipping
Full plates are banded and dunnaged; cut parts are nested on pallets with edge protection and part-number marking matching your drawing set. Containerized for ≤ 24-ton lots, breakbulk for larger. We ship FOB, CFR, CIF and DAP from major Chinese ports; typical lead time is 15–30 days depending on cutting scope, with stock sizes available sooner.
Why Buy NM400 from Huaxia-Steel
- Factory-direct from audited quench-and-temper mills — genuine Q/QT microstructure, not re-rolled plate.
- Cut-to-size service: send DXF/DWG files, receive finished liners with reports.
- Honest grade guidance: if NM360 or NM450 serves your duty cycle better, we say so and quote accordingly.
- One-shipment consolidation with structural plate, pipe and sections for your project.
Request NM400 pricing. Send your plate list or cutting drawings to [email protected] or the inquiry form — factory quotation and hardness certificates within 24 hours.
