Steel 17Mn4 · heat-treated state
Steel 17Mn4 Q&T
Properties of the Q&T condition, compared with the other 17Mn4 tempers.
Only for small forgings/thin parts where extra yield strength is wanted; low hardenability of 0.17 C–1.2 Mn limits response in thick sections and it is rarely a code delivery condition.
What is 17Mn4 Q&T?
17Mn4 Q&T is 17Mn4 heat treated to Q&T — only for small forgings/thin parts where extra yield strength is wanted; low hardenability of 0.17 C–1.2 Mn limits response in thick sections and it is rarely a code delivery condition. 17Mn4 Q&T has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 53% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi). 17Mn4 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F). HR is the default condition FabDigit quotes; Q&T is available on request or by drawing note.
Advantages
- Easy to machine — 60/100, better than 83% of steel grades
- Readily welded — 85/100, better than 83% of steel grades
- Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 80% of steel grades
- Conducts heat well — 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
17Mn4 Q&T properties
Typical room-temperature values for 17Mn4 Q&T — 9 properties are specific to this condition; the rest are grade-level values shared by every 17Mn4 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
17Mn4 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F).
Mechanical15
17Mn4 Q&T has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 53% of steel grades. Elongation at break is 20% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
17Mn4 Q&T is rated for continuous service to 400°C (752 °F). It conducts heat at 48 W/m·K (27.7 BTU/hr·ft·°F), better than 79% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
17Mn4 Q&T conducts electricity at 9 % IACS, better than 70% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 17Mn4 Q&T takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
17Mn4 Q&T's machinability is good (60/100, better than 83% of steel grades); weldability excellent (85/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other 17Mn4 tempers and conditions
17Mn4 is also supplied in 5 other conditions. The full side-by-side table is on the 17Mn4 overview.
- HRDefaultCheapest form for non-code structural or machining stock where certified toughness in the normalized condition is not required.330 MPa yield · 155 HB
- Q&TOnly for small forgings/thin parts where extra yield strength is wanted; low hardenability of 0.17 C–1.2 Mn limits response in thick sections and it is rarely a code delivery condition.450 MPa yield · 15 HRC
- NormalizedPick for boiler drums, steam headers and code-stamped pressure parts — best combination of guaranteed ReH, RT/low-temperature toughness and weldability.325 MPa yield · 150 HB
Working with 17Mn4 Q&T
Is 17Mn4 easy to machine?
Machines like normalized 1020–1025 steel at ~65 % of AISI 1212; use sharp positive-rake carbide, generous feed and coolant to avoid gummy chips and built-up edge.
Can 17Mn4 be welded?
Readily weldable by SMAW/GMAW/SAW with matching C-Mn consumables; CEV ≈ 0.40 so preheat 100–150 °C above ~30 mm and PWHT 550–620 °C where the pressure code requires it.
Can 17Mn4 be formed, bent or molded?
Good cold bendability in the normalized condition (min bend radius ≈ 2 t); hot form 900–1050 °C and re-normalize afterwards to restore certified properties.
What surface finishes work on 17Mn4?
No anodizing; shot blast then paint, phosphate, hot-dip galvanize or zinc-plate — bare surfaces rust quickly, and boiler internals rely on water chemistry plus corrosion allowance.
17Mn4 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 |
|---|---|---|
| Cladle analysis, EN 10028-2 P295GH | 0.08 – 0.2 | 0.17 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.9 – 1.5 | 1.2 |
| P | ≤ 0.03 | 0.02 |
| S0.010 max for some deliveries | ≤ 0.02 | 0.01 |
| Altotal Al, fully killed / fine grain | ≥ 0.02 | 0.03 |
| Crresidual | ≤ 0.3 | 0.08 |
| Curesidual | ≤ 0.3 | 0.1 |
| Niresidual | ≤ 0.3 | 0.1 |
| Moresidual | ≤ 0.08 | 0.02 |
| Nb | ≤ 0.02 | — |
| Ti | ≤ 0.03 | — |
| V | ≤ 0.02 | — |
| N | ≤ 0.01 | — |
| Fe | balance | — |
17Mn4 Q&T — frequently asked
What is 17Mn4 Q&T used for?
17Mn4 Q&T is typically used for welded boiler drums and shells, pressure vessel shells and heads, steam piping and headers, heat exchanger shells, air receivers and tube plates and vessel flanges. In short: workhorse mild-steel plate.
What is the yield strength of 17Mn4 Q&T?
17Mn4 Q&T has a typical yield strength of 450 MPa (65.3 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 53% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is 17Mn4 Q&T easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machines like normalized 1020–1025 steel at ~65 % of AISI 1212; use sharp positive-rake carbide, generous feed and coolant to avoid gummy chips and built-up edge.
Can 17Mn4 Q&T be welded?
Yes — weldability is rated excellent (85/100). Readily weldable by SMAW/GMAW/SAW with matching C-Mn consumables; CEV ≈ 0.40 so preheat 100–150 °C above ~30 mm and PWHT 550–620 °C where the pressure code requires it.
What surface finishes work on 17Mn4 Q&T?
No anodizing; shot blast then paint, phosphate, hot-dip galvanize or zinc-plate — bare surfaces rust quickly, and boiler internals rely on water chemistry plus corrosion allowance.
Can 17Mn4 Q&T be formed, bent or molded?
Good cold bendability in the normalized condition (min bend radius ≈ 2 t); hot form 900–1050 °C and re-normalize afterwards to restore certified properties.
What is the maximum service temperature of 17Mn4 Q&T?
17Mn4 Q&T is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 17Mn4-HR and 17Mn4-CD?
HR is the default condition — cheapest form for non-code structural or machining stock where certified toughness in the normalized condition is not required. CD: bar stock for machined fittings and flange blanks — higher yield, better surface and straightness than hot-rolled bar. Yield strength is 330 MPa in HR versus 480 MPa in CD.
Can FabDigit make parts in 17Mn4 Q&T?
Yes — 17Mn4 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
- DIN 17155 — Plates and strips of steels for pressure purposes (17Mn4) — DIN (1983)
- EN 10028-2 — Flat products of steels for pressure purposes: non-alloy and alloy steels with elevated temperature properties (P295GH, 1.0481) — CEN (2017)
- EN 10027-2 — Designation systems for steels: steel numbers — CEN (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- AD 2000-Merkblatt W1 — Flat products of ferritic steels for pressure vessels — Verband der TÜV (2018)
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.