Steel AR400
GB NM400 · also Hardox 400
AR400 is a proprietary through-hardened, quenched-and-tempered low-alloy abrasion-resistant steel plate supplied at a nominal 400 HB (typically 360–440 HB) wear surface.
Values for the Q&T condition
AR400 tempers and conditions
AR400 is supplied in 2 conditions, soft to hard. Q&T is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Q&TDefault Quenched and tempered | Standard stocked abrasion-resistant plate — pick for general sliding-wear liners, chutes and bucket wear parts. | 1,050 | 1,250 | 11 | 43 HRC | — |
Formable / impact-tested fine-grain AR400 with guaranteed… | Choose when the wear part must be cold-formed to tighter radii or must survive impact and sub-zero service (guaranteed Charpy, often at −40 °C). | 1,100 | 1,250 | 12 | 43 HRC | — |
Supply forms, finishes and certifications
Ways AR400 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
MILD-BACKED | Mild-backed / dual-hardness composite plate | Supply option |
What is AR400?
AR400 is a proprietary through-hardened, quenched-and-tempered low-alloy abrasion-resistant steel plate supplied at a nominal 400 HB (typically 360–440 HB) wear surface. It is chosen for sliding/impact wear parts — dump-body and bucket liners, chutes, crusher wear plate, screen decks — where mild steel wears out too quickly and hardened tool steel is too costly or brittle. It is a wear grade, not a structural design grade: yield/tensile are not guaranteed by the mills, cold forming and welding require care (preheat, low-hydrogen consumables, HAZ softening) and machining is slow. AR400 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). AR400 has a yield strength of 1,050 MPa (152 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 93% of steel grades. Elongation at break is 11% and the elastic modulus is 205 GPa (29.7 Msi).
What is AR400 used for?
- Dump-body and truck-bed liners
- Excavator and loader bucket liners
- Chute and hopper liners
- Crusher wear plate
- Screen decks
- Conveyor skirting and transfer-point liners
- Mixer and silo liners
Advantages
- High strength — 1,050 MPa (152 ksi), better than 93% of steel grades
Limitations
- Difficult to machine — 22/100, worse than 95% of steel grades
- Limited ductility — 11%, worse than 89% of steel grades
- Limited service temperature — 250°C (482 °F), worse than 85% of steel grades
AR400 properties
Typical room-temperature values for AR400-Q&T; bars are the position among steel grades.
Physical3
AR400 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
AR400 has a yield strength of 1,050 MPa (152 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 93% of steel grades. Elongation at break is 11% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
AR400 is rated for continuous service to 250°C (482 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
AR400 conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental2
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of AR400 takes about 28 MJ of energy and emits 2.3 kg of CO₂ — less than 56% of steel grades. Typical recycled content is 25%.
Manufacturability7
AR400's machinability is poor (22/100, worse than 95% of steel grades); weldability good (55/100); formability poor (25/100).
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. AR400 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with AR400
Is AR400 easy to machine?
Treat as 40+ HRC steel: rigid setup, negative-rake carbide or CBN, low speed with heavy feed; drilling needs cobalt/carbide or better annealed-then-reharden planning — plasma/laser/waterjet cutting is usually cheaper than machining.
Can AR400 be welded?
Weldable with low-hydrogen consumables (E7018/ER70S-6 class, softer than base plate); control preheat 100–200 °C by thickness/CEV, keep interpass below ~250 °C and avoid stress-relief that would temper the wear face.
Can AR400 be formed, bent or molded?
Cold bend transverse to rolling direction with inside radius ≈4–5 × thickness (tighter on AR400F); avoid punching thick sections and always grind flame-cut edges before bending to prevent edge cracking.
Manufacturability
The process limits FabDigit's quote engine applies to AR400. Design inside these and the part quotes instantly; outside them it routes to an engineer.
CNC machining
| Machinability | Fair22 / 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 | Fair25 / 100 |
|---|---|
| Weldability | Fair55 / 100 |
AR400 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 |
|---|---|---|
| Cmill-specific; CEV controls preheat | 0.18 – 0.3 | 0.24 |
| Si | 0.15 – 0.6 | 0.35 |
| Mn | 0.8 – 1.7 | 1.3 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.01 | 0.01 |
| Crhardenability addition | ≤ 1 | 0.5 |
| Nihigher in AR400F for toughness | ≤ 1 | 0.3 |
| Mo | ≤ 0.6 | 0.25 |
| Bboron-treated for through-hardening | 5×10⁻⁴ – 0.01 | 0 |
| Fe | balance |
What surface finishes work on AR400?
No anodizing; shot-blast and use zinc-rich primer plus epoxy/polyurethane paint for corrosion protection, or hardfacing overlay to extend wear life on hot spots.
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 AR400 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- GB (China)
- NM400
- Trade names
- Hardox 400
How much does AR400 cost?
AR400 is a premium-cost steel ($$$), cheaper than about 60% 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.
AR400 — frequently asked
What is AR400 used for?
AR400 is typically used for dump-body and truck-bed liners, excavator and loader bucket liners, chute and hopper liners, crusher wear plate, screen decks and conveyor skirting and transfer-point liners. In short: extreme abrasion resistance.
What is the yield strength of AR400?
AR400 has a typical yield strength of 1,050 MPa (152 ksi) and a tensile strength of 1,250 MPa (181 ksi) — stronger than 93% of steel grades. Strength varies by condition: see the 2 listed tempers.
Is AR400 easy to machine?
Not especially — machinability is rated poor (22/100, worse than 95% of steel grades). Treat as 40+ HRC steel: rigid setup, negative-rake carbide or CBN, low speed with heavy feed; drilling needs cobalt/carbide or better annealed-then-reharden planning — plasma/laser/waterjet cutting is usually cheaper than machining.
Can AR400 be welded?
Yes — weldability is rated good (55/100). Weldable with low-hydrogen consumables (E7018/ER70S-6 class, softer than base plate); control preheat 100–200 °C by thickness/CEV, keep interpass below ~250 °C and avoid stress-relief that would temper the wear face.
What surface finishes work on AR400?
No anodizing; shot-blast and use zinc-rich primer plus epoxy/polyurethane paint for corrosion protection, or hardfacing overlay to extend wear life on hot spots.
Can AR400 be formed, bent or molded?
Cold bend transverse to rolling direction with inside radius ≈4–5 × thickness (tighter on AR400F); avoid punching thick sections and always grind flame-cut edges before bending to prevent edge cracking.
What is the maximum service temperature of AR400?
AR400 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.
What is the difference between AR400 Q&T and AR400F?
Q&T is the default condition — standard stocked abrasion-resistant plate — pick for general sliding-wear liners, chutes and bucket wear parts. AR400F: choose when the wear part must be cold-formed to tighter radii or must survive impact and sub-zero service (guaranteed Charpy, often at −40 °C). Yield strength is 1,050 MPa in Q&T versus 1,100 MPa in AR400F.
How much does AR400 cost?
AR400 is a premium-cost steel ($$$), cheaper than about 60% 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 AR400?
Yes — AR400 is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- GB/T 24186 — Wear-resistant steel plate for construction machinery (NM400) — SAC (2022)
- Abrasion-resistant quenched & tempered plate 400 HB — typical properties and fabrication guide — AR plate mills / service centers (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.19 — Fatigue and Fracture — ASM International (1996)
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.