Steel Hardox 400
GB NM400
Hardox 400 is a proprietary SSAB quenched and tempered abrasion-resistant plate at a nominal 400 HBW (43 HRC), in the same class as NM400.
Values for the Q&T condition
Hardox 400 tempers and conditions
Hardox 400 is supplied in 3 conditions, soft to hard. Q&T is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Quenched & Tempered, higher CEV | Heavy-gauge Q&T plate for crusher parts and large wear blocks; needs higher preheat when welding and shows slightly lower core hardness. | 950 | 1,200 | 10 | 42 HRC | 7 % IACS |
Q&TDefault Quenched and tempered | Standard as-delivered Hardox 400 plate condition for all abrasion-resistant applications. | 1,000 | 1,250 | 10 | 43 HRC | — |
Quenched & Tempered, guaranteed 45 J at -40 °C | Thin-gauge Q&T plate/coil for liners, chutes and cold-bent wear parts where formability and full toughness are needed. | 1,000 | 1,250 | 11 | 43 HRC | 7 % IACS |
What is Hardox 400?
Hardox 400 is a proprietary SSAB quenched and tempered abrasion-resistant plate at a nominal 400 HBW (43 HRC), in the same class as NM400. The through-hardened structure gives about 1000 MPa yield, 1250 MPa tensile and 10 % elongation, so it carries load as well as resisting wear; thin and thick Q&T plate variants are available. Service temperature is capped near 250 °C because heating tempers the plate, corrosion resistance is that of plain steel, and profiling is normally thermal or waterjet rather than milling. Hardox 450 or 500 gives more wear life where forming limits allow. Hardox 400 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). Hardox 400 has a yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 92% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
What is Hardox 400 used for?
- Excavator and loader bucket liners
- Mining shovel wear parts
- Dump-body and chute liners
- Crusher and screen wear plates
- Conveyor skirt and scraper blades
- Dozer blade cutting edges
- Wear strips and liner blocks
Advantages
- High strength — 1,000 MPa (145 ksi), better than 92% of steel grades
Limitations
- Difficult to machine — 25/100, worse than 93% of steel grades
- Limited ductility — 10%, worse than 91% of steel grades
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
- Poor heat conductor — 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades
Hardox 400 properties
Typical room-temperature values for Hardox 400-Q&T; bars are the position among steel grades.
Physical3
Hardox 400 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
Hardox 400 has a yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 92% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
Hardox 400 is rated for continuous service to 250°C (482 °F). It conducts heat at 34 W/m·K (19.6 BTU/hr·ft·°F), worse than 77% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
Hardox 400 conducts electricity at 7 % IACS, worse than 74% of steel grades.
Chemical & Environmental2
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of Hardox 400 takes about 30 MJ of energy and emits 2.1 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 25%.
Manufacturability6
Hardox 400's machinability is poor (25/100, worse than 93% of steel grades); weldability good (60/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. Hardox 400 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Hardox 400
Is Hardox 400 easy to machine?
Machinable with rigid setups, coated carbide and reduced speeds/feeds; drilling needs low rpm and high feed pressure — plasma/laser/waterjet cutting is usually preferred over milling.
Can Hardox 400 be welded?
Good weldability with low-hydrogen consumables (soft or matching), preheat 75–150 °C depending on thickness and joint restraint; keep heat input low to limit HAZ softening.
Can Hardox 400 be formed, bent or molded?
Cold bendable transverse to rolling direction with generous inside radii (≈3–4× t) and press-brake dies sized for 1000 MPa yield; hot forming above 250 °C destroys the temper.
Manufacturability
The process limits FabDigit applies to Hardox 400. Every Hardox 400 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Fair25 / 100 |
|---|---|
| ISO material group | P.2 |
| Cutting speed (rough / finish) | 180 / 210 m/min |
| Minimum wall | 0.8 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 5× diameter |
| Best surface (machined / polished) | Ra 1.6 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair40 / 100 |
|---|---|
| Weldability | Better60 / 100 |
Hardox 400 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cmax depends on thickness (0.15 % thin – 0.32 % thick) | ≤ 0.32 | 0.16 |
| Si | ≤ 0.7 | 0.3 |
| Mn | ≤ 1.6 | 1.2 |
| P | ≤ 0.03 | |
| S | ≤ 0.01 | |
| Crhardenability addition, thickness dependent | ≤ 1.4 | 0.5 |
| Nithickness dependent | ≤ 1.5 | 0.25 |
| Mothickness dependent | ≤ 0.6 | 0.15 |
| Bboron for hardenability | ≤ 0.01 | 0 |
| Fe | balance |
What surface finishes work on Hardox 400?
Shot-blast and paint or zinc-rich prime for corrosion protection; hardfacing overlays can be applied where wear exceeds base-plate life.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
CVD Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel Hardox 400 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
How much does Hardox 400 cost?
Hardox 400 is a standard-cost steel ($$), cheaper than about 59% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Hardox 400 — frequently asked
What is Hardox 400 used for?
Hardox 400 is typically used for excavator and loader bucket liners, mining shovel wear parts, dump-body and chute liners, crusher and screen wear plates, conveyor skirt and scraper blades and dozer blade cutting edges. In short: workhorse abrasion wear plate.
What is the yield strength of Hardox 400?
Hardox 400 has a typical yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 92% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is Hardox 400 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of steel grades). Machinable with rigid setups, coated carbide and reduced speeds/feeds; drilling needs low rpm and high feed pressure — plasma/laser/waterjet cutting is usually preferred over milling.
Can Hardox 400 be welded?
Yes — weldability is rated good (60/100). Good weldability with low-hydrogen consumables (soft or matching), preheat 75–150 °C depending on thickness and joint restraint; keep heat input low to limit HAZ softening.
What surface finishes work on Hardox 400?
Shot-blast and paint or zinc-rich prime for corrosion protection; hardfacing overlays can be applied where wear exceeds base-plate life.
Can Hardox 400 be formed, bent or molded?
Cold bendable transverse to rolling direction with generous inside radii (≈3–4× t) and press-brake dies sized for 1000 MPa yield; hot forming above 250 °C destroys the temper.
What is the maximum service temperature of Hardox 400?
Hardox 400 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does Hardox 400 cost?
Hardox 400 is a standard-cost steel ($$), cheaper than about 59% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in Hardox 400?
Yes — Hardox 400 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- Hardox 400 — Data Sheet, abrasion-resistant steel plate — SSAB (2024)
- Welding and cutting of Hardox / WearCalc guidance — SSAB (2023)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASTM E140 — Standard Hardness Conversion Tables for Metals — ASTM (2019)
- GB/T 24186 — (NM400 comparison) — SAC (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.