Steel Hardox 450 · heat-treated state · default condition
Steel Hardox 450 Q&T
Properties of the Q&T condition, compared with the other Hardox 450 tempers.
Standard as-delivered Hardox 450 plate 3.2–70 mm — the condition in which essentially all Hardox 450 is stocked and used.
What is Hardox 450 Q&T?
Hardox 450 Q&T is Hardox 450 heat treated to Q&T — standard as-delivered Hardox 450 plate 3.2–70 mm — the condition in which essentially all Hardox 450 is stocked and used. Hardox 450 Q&T has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,400 MPa (203 ksi) — stronger than 94% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi). Hardox 450 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F).
Advantages
- High strength — 1,200 MPa (174 ksi), better than 94% of steel grades
Limitations
- Difficult to machine — 22/100, worse than 96% 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
Hardox 450 Q&T properties
Typical room-temperature values for Hardox 450 Q&T — 10 properties are specific to this condition; the rest are grade-level values shared by every Hardox 450 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
Hardox 450 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F).
Mechanical16
Hardox 450 Q&T has a yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,400 MPa (203 ksi) — stronger than 94% of steel grades. Elongation at break is 10% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
Hardox 450 Q&T is rated for continuous service to 250°C (482 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 68% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
Hardox 450 Q&T conducts electricity at 7 % IACS, worse than 74% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of Hardox 450 Q&T takes about 30 MJ of energy and emits 2.4 kg of CO₂ — more than 55% of steel grades. Typical recycled content is 25%.
Manufacturability5
Hardox 450 Q&T's machinability is poor (22/100, worse than 96% of steel grades); weldability good (55/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other Hardox 450 tempers and conditions
Hardox 450 is also supplied in 2 other conditions. The full side-by-side table is on the Hardox 450 overview.
- Q&TDefaultStandard as-delivered Hardox 450 plate 3.2–70 mm — the condition in which essentially all Hardox 450 is stocked and used.1,200 MPa yield · 47 HRC
Working with Hardox 450 Q&T
Is Hardox 450 easy to machine?
Treat as 47 HRC material: rigid setups, coated carbide or CBN, low speed/high feed, no interrupted-cut chatter; drilling needs cobalt or carbide and coolant flood.
Can Hardox 450 be welded?
Fully weldable with low-hydrogen consumables of undermatching strength; keep preheat 75–150 °C (thickness dependent), limit heat input and interpass temperature to protect the HAZ, no PWHT.
Can Hardox 450 be formed, bent or molded?
Cold-bend transverse to rolling direction with inner radius ≥3×t and generous die opening; do not hot-form above ~250 °C or hardness will be lost permanently.
What surface finishes work on Hardox 450?
Shot-blast and prime/paint for any wet or outdoor service; plate takes zinc-rich primers and epoxy well, plating is rarely used and hydrogen embrittlement must be considered.
Hardox 450 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 |
|---|---|---|
| C0.19 % max for t ≤ 20 mm, up to 0.26 % for heavy plate | ≤ 0.26 | 0.21 |
| Si | ≤ 0.7 | 0.3 |
| Mn | ≤ 1.6 | 1.3 |
| P | ≤ 0.03 | — |
| S | ≤ 0.01 | — |
| Cr | ≤ 1.4 | 0.5 |
| Nihigher in heavy gauges | ≤ 1.5 | 0.25 |
| Mo | ≤ 0.6 | 0.2 |
| Bhardenability booster | ≤ 0.01 | 0 |
| Febalance; micro-alloyed and fine-grain treated | balance | — |
Hardox 450 Q&T — frequently asked
What is Hardox 450 Q&T used for?
Hardox 450 Q&T is typically used for mining and hopper liners, crusher plates, excavator and loader bucket wear plates, chute and skirt liners, dump body panels and grader and cutting edges. In short: premium abrasion wear plate.
What is the yield strength of Hardox 450 Q&T?
Hardox 450 Q&T has a typical yield strength of 1,200 MPa (174 ksi) and a tensile strength of 1,400 MPa (203 ksi) — stronger than 94% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is Hardox 450 Q&T easy to machine?
Not especially — machinability is rated poor (22/100, worse than 96% of steel grades). Treat as 47 HRC material: rigid setups, coated carbide or CBN, low speed/high feed, no interrupted-cut chatter; drilling needs cobalt or carbide and coolant flood.
Can Hardox 450 Q&T be welded?
Yes — weldability is rated good (55/100). Fully weldable with low-hydrogen consumables of undermatching strength; keep preheat 75–150 °C (thickness dependent), limit heat input and interpass temperature to protect the HAZ, no PWHT.
What surface finishes work on Hardox 450 Q&T?
Shot-blast and prime/paint for any wet or outdoor service; plate takes zinc-rich primers and epoxy well, plating is rarely used and hydrogen embrittlement must be considered.
Can Hardox 450 Q&T be formed, bent or molded?
Cold-bend transverse to rolling direction with inner radius ≥3×t and generous die opening; do not hot-form above ~250 °C or hardness will be lost permanently.
What is the maximum service temperature of Hardox 450 Q&T?
Hardox 450 Q&T 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.
Can FabDigit make parts in Hardox 450 Q&T?
Yes — Hardox 450 Q&T 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
- Hardox 450 Data Sheet (abrasion-resistant steel plate) — SSAB (2023)
- Hardox Wearparts / Welding of Hardox and Strenx — SSAB (2022)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- GB/T 24186 (NM450 comparison) — SAC (2022)
- (Hardox/NM450) — Mysteel / 1688 (2026)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.