HB 400 Steel Plates (HB400 Wear Resistant Plate) Supplier
ASC LLP, Mumbai, supplies HB 400 steel plates – quenched, abrasion-resistant plates with a nominal hardness of 400 Brinell – from 6 mm to 100 mm thick. We stock and source HB400 plates from leading mills, including Hardox 400, Rockstar 400 (AM/NS India) and NM400, with mill test certificates, cut-to-size profiles and delivery across India and for export.
What is HB 400 Steel?
HB 400 steel (also written HB400, “Hardened 400” or “400 BHN”) is a low-alloy, boron-bearing martensitic steel plate that is water-quenched at the mill to a surface hardness of about 370–430 HBW. “HB 400” is a hardness class rather than a single standard grade: each mill sells it under its own brand name (Hardox 400, Rockstar 400, Abrex 400 and others), and each mill sets its own hardness band, thickness range, toughness and chemistry. Wear life compared with mild steel depends on the abrasive, impact and sliding angle, so no fixed multiplier applies; the mill’s data sheet and a trial in your own service are the reliable guide.
Because the hardness comes from quenching rather than high alloy content, HB 400 plate offers the best balance of wear resistance, toughness and workshop-friendliness of the wear-plate classes, which is why it is the most widely used grade for dumper bodies, buckets, chutes and liners.
Key Properties of HB 400 Plates
- High abrasion resistance: 370–430 HBW surface hardness resists sliding wear from sand, coal, ore, gravel and aggregates.
- High strength: yield strength around 1000 MPa, roughly four times that of mild steel, allowing thinner and lighter wear parts.
- Good toughness: withstands impact from rocks and lumps; typical Charpy values differ by mill and test temperature (for example about 45 J at –40 °C for Hardox 400, but about 30 J at –20 °C for Abrex 400), so check the mill data if impact at low temperature matters.
- Weldable and bendable: can be welded with low-hydrogen consumables and cold-formed with suitable bend radii.
- Not corrosion resistant: HB 400 is a low-alloy steel and will rust like mild steel; paint or coat it where corrosion is a concern.
HB 400 vs HB 450 vs HB 500 Plates
| Property | HB 400 | HB 450 | HB 500 |
| Hardness range (typical) | 370 – 430 HBW | 425 – 475 HBW | 470 – 530 HBW |
| Wear resistance | High | Higher | Highest |
| Toughness / impact resistance | Best | Good | Moderate |
| Ease of bending & welding | Easiest | Moderate | Most demanding |
| Typical brands | Hardox 400, Rockstar 400, NM400 | Hardox 450, Rockstar 450, NM450 | Hardox 500, Rockstar 500, NM500 |
| Typical use | Dumper bodies, buckets, chutes, general liners | Heavy-wear tippers, bucket lips, crusher liners | Severe sliding wear: cutting edges, screens, liners |
Summary: choose HB 400 when parts need to be bent, welded and take impact; move to HB 450 or HB 500 when pure sliding wear dominates and fabrication is simple.
Applications of HB 400 Plates
- Mining & quarrying: dumper and tipper bodies, crusher liners, feeder and hopper liners.
- Construction & earthmoving: excavator and loader buckets, bulldozer blades, side cutters.
- Bulk material handling: chutes, transfer points, conveyor skirts and silo liners.
- Cement, steel & power plants: coal and clinker handling, ash handling and fan liners.
- Recycling: shredder parts, scrap-handling buckets and containers.
- Agriculture: ploughs, tillage tools and harvester wear parts.
HB 400 Plate Specifications & Sizes
| Item | Details |
| Hardness class | HB 400 (370 – 430 HBW nominal) |
| Brands / mill grades | Hardox 400, Rockstar 400, NM400 (GB/T 24186), Raex 400, XAR 400 and equivalents |
| Thickness | 6 – 100 mm (thinner sheet and thicker plate on request) |
| Width | 1500 – 2500 mm (mill dependent) |
| Length | 6000 – 12000 mm; cut-to-size and profiles on request |
| Delivery condition | Quenched, or quenched & tempered |
| Thickness tolerance | EN 10029 / mill standard |
| Edges | Mill, sheared or thermally cut |
| Test certificate | EN 10204 3.1 mill test certificate |
Plate weight: 7.85 kg per m² per mm of thickness. For example, a 10 mm HB 400 plate weighs about 78.5 kg/m², and a 2500 × 6000 × 10 mm plate weighs about 1,178 kg.
Chemical Composition of HB 400 Plates
| Element | Hardox 400 (max %) | NM400 – GB/T 24186 (max %) |
| Carbon (C) | 0.32 | 0.30 |
| Silicon (Si) | 0.70 | 0.70 |
| Manganese (Mn) | 1.60 | 1.60 |
| Phosphorus (P) | 0.025 | 0.025 |
| Sulphur (S) | 0.010 | 0.010 |
| Chromium (Cr) | 2.50 | 1.20 |
| Nickel (Ni) | 1.50 | 0.70 |
| Molybdenum (Mo) | 0.60 | 0.50 |
| Boron (B) | 0.004 | 0.0005 – 0.006 |
Maximum values vary with plate thickness – thicker plates carry more alloy for through-hardening. Actual analysis is shown on the mill certificate.
Mechanical Properties & Hardness of HB 400 Plates
| Property | Typical value |
| Surface hardness | 370 – 430 HBW (Rockstar 400: 360 – 430 BHN) |
| Yield strength | approx. 1000 – 1100 MPa, depending on mill (typical, not guaranteed) |
| Tensile strength | approx. 1200 – 1250 MPa |
| Elongation | approx. 10 – 12% |
| Charpy V impact | Mill dependent – e.g. about 45 J at –40 °C (Hardox 400) or about 30 J at –20 °C (Abrex 400); typical, not guaranteed |
| Maximum service temperature | approx. 250 °C – hardness drops above this |
Values are typical for plates around 20–25 mm thick. Normally only hardness is guaranteed; strength and impact are guaranteed only if ordered, and limits depend on the mill and thickness.
HB 400 Steel Grades by Mill – Comparison
| Brand (mill) | Guaranteed hardness | Plate thickness | Typical yield / impact | Mill data sheet |
| Hardox 400 (SSAB) | 370 – 430 HBW | 4 – 130 mm | about 1100 MPa; about 45 J at –40 °C | SSAB Hardox 400 |
| Rockstar 400 (AM/NS India) | 360 – 430 BHN | 6 – 80 mm | about 1000 MPa; about 40 J at –30 °C | AM/NS India heavy plates |
| Abrex 400 (Nippon Steel) | 360 – 440 HBW | 6 – 100 mm | about 1025 MPa; about 30 J at –20 °C | Nippon Steel ABREX catalogue |
Other mills also make 400-class plates (for example NM400 to the Chinese standard GB/T 24186, and the generic US class AR400). Hardness bands, thickness limits, toughness and chemistry differ between all of these grades, so they are not automatically interchangeable.
Before Substituting One Brand for Another
- Thickness: the required thickness must be inside the substitute mill’s range.
- Hardness band: compare the guaranteed range, not the nominal 400.
- Impact: if the drawing specifies Charpy values or a test temperature, the substitute must guarantee them.
- Welding: check carbon equivalent and the mill’s preheat table, because the welding procedure may need requalifying.
- Approval: where a drawing or specification names a brand, get written approval from the buyer or designer before substituting.
Physical Properties of HB 400 Steel
| Property | Value (approx.) |
| Density | 7.85 g/cm³ |
| Modulus of elasticity | approx. 205 – 210 GPa |
| Magnetic | Yes (ferromagnetic) |
| Plate weight | 7.85 kg/m² per mm thickness |
Cutting, Bending & Welding HB 400 Plates
- Cutting: plasma, laser, oxy-fuel and waterjet are all used. Thicker plates need preheating before thermal cutting to avoid cracking at cut edges; waterjet avoids heat effects entirely.
- Bending: HB 400 can be cold-bent, but needs a larger punch radius and die opening than mild steel – follow the mill’s minimum bend radius for the thickness, and allow for more springback.
- Welding: use low-hydrogen consumables, keep joints clean and dry, and preheat thicker plates as per the mill’s guidelines. Keep interpass temperature low so the plate does not lose hardness near the weld.
- Machining: drilling and countersinking are possible with carbide or cobalt HSS tools at low speeds and rigid set-ups.
How to choose: tell us the material being handled, whether wear is sliding or impact, the plate size and any bending or welding involved – we will recommend HB 400 or a harder grade and a suitable brand.
Why Buy HB 400 Plates from ASC LLP?
- Brand as specified: we supply the mill brand named on your drawing, with that mill’s test certificate, and help compare alternatives where substitution is allowed.
- Certified material: EN 10204 3.1 mill test certificates; hardness verification and third-party inspection on request.
- Cut-to-size: plates, strips and profile-cut parts as per drawing.
- India-wide & export supply: prompt dispatch from Mumbai with export-worthy packing.
Related Plates Products
Frequently Asked Questions – HB 400 Steel Plates
What is HB 400 steel?
HB 400 steel is a quenched, low-alloy abrasion-resistant steel plate with a nominal Brinell hardness of 400 (typically 370–430 HBW). It is sold under brand names such as Hardox 400, Rockstar 400 and NM400.
What is the hardness of HB 400 plate?
HB 400 plates have a surface hardness of about 370–430 HBW. Some mills, such as AM/NS India for Rockstar 400, specify 360–430 BHN.
What is the equivalent of HB 400 steel?
Grades in the same 400 HBW class include Hardox 400 (SSAB), Rockstar 400 (AM/NS India), Abrex 400 (Nippon Steel), NM400 (GB/T 24186) and AR400. However, they are a class, not exact equivalents: hardness band, thickness range, toughness and chemistry differ by mill.
Is Rockstar 400 the same as Hardox 400?
Both are HB 400-class wear plates from different mills – Rockstar 400 from AM/NS India and Hardox 400 from SSAB. They are not automatically interchangeable: Hardox 400 is made from 4 to 130 mm with 370–430 HBW, whereas Rockstar 400 is made from 6 to 80 mm with 360–430 BHN, and typical toughness and chemistry also differ. Therefore check thickness, impact and welding requirements, and get approval if a drawing names a specific brand.
Can HB 400 plates be welded and bent?
Yes. HB 400 can be welded with low-hydrogen consumables (with preheat for thicker plates) and cold-bent using a larger bend radius than mild steel, following the mill’s guidelines.
What is the difference between HB 400 and HB 500?
HB 500 is harder (about 470–530 HBW) and lasts longer under pure sliding wear, while HB 400 is tougher and easier to bend and weld. HB 400 is preferred for parts that take impact or need fabrication.
Global Reach
ASC LLP serves customers across India and around the world with prompt delivery and dependable support. Mining, construction and equipment manufacturers in the Middle East, Africa, Asia and beyond rely on our HB 400 wear resistant plates for consistent hardness, documentation and cut-to-size service.
Countries We Export To
UNITED STATES, EUROPE, UK, UAE, SAUDI ARABIA, OMAN, KUWAIT, JORDAN, QATAR, INDONESIA, MALAYSIA, BRAZIL, SPAIN, ITALY, FRANCE, GERMANY, BAHRAIN, SRI LANKA, AZERBAIJAN, AUSTRALIA, AUSTRIA, PHILIPPINES, TURKEY, RUSSIA, IRAN, IRAQ, CANADA, KOREA, JAPAN, YEMEN, FINLAND, ZIMBABWE, HUNGARY, PORTUGAL, VIETNAM, MOROCCO, THAILAND, SOUTH AFRICA, MEXICO, SINGAPORE, GREECE, KUWAIT, POLAND, NEW ZEALAND, SWEDEN, SWITZERLAND, BELGIUM, BHUTAN, BANGLADESH, TAIWAN, ROMANIA, CAMBODIA, KAZAKHSTAN, AFGHANISTAN.
