Stainless Steel 1.4003-QT (Quenched and tempered)
Heat-treated state
EN 1.4003 · UNS S41003 · also 3CR12
Niche supply where higher strength/abrasion resistance is wanted; sacrifices toughness and weldability, needs post-weld heat treatment.
Values for the QT condition
Other 1.4003 tempers and conditions
1.4003 is listed in 4 conditions; see the grade overview at 1.4003.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed 2B/2D | Pick for sheet ≤ 4 mm needing a smoother surface and press forming (panels, tanks, ducting). | 350 | 500 | 25 | 165 HB | — |
Hot rolled | Cheapest structural supply for heavy plate where surface and maximum ductility are not critical. | 365 | 520 | 22 | 180 HB | 2.9 % IACS |
Temper Rolled / lightly cold worked strip | Choose when flatness, spring-back and higher yield strength matter more than deep-drawing ductility. | 480 | 600 | 10 | 14 HRC | 2.9 % IACS |
QTThis page Quenched and tempered | Niche supply where higher strength/abrasion resistance is wanted; sacrifices toughness and weldability, needs post-weld heat treatment. | 550 | 700 | 16 | 22 HRC | 2.8 % IACS |
What is 1.4003-QT?
1.4003-QT is 1.4003 heat treated to QT — niche supply where higher strength/abrasion resistance is wanted; sacrifices toughness and weldability, needs post-weld heat treatment. 1.4003-QT has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 83% of stainless steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi). 1.4003-QT has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,450°C (2,642 °F).
Advantages
- Low embodied carbon — 2.9 kg CO₂/kg, better than 98% of stainless steel grades
- Conducts heat well — 29 W/m·K (16.8 BTU/hr·ft·°F), better than 97% of stainless steel grades
- Easy to machine — 45/100, better than 84% of stainless steel grades
- High strength — 550 MPa (79.8 ksi), better than 83% of stainless steel grades
- High electrical conductivity — 2.8 % IACS, better than 79% of stainless steel grades
Limitations
- Needs corrosion protection — 38/100, worse than 95% of stainless steel grades
- Hard to polish — 50/100, worse than 93% of stainless steel grades
- Limited ductility — 16%, worse than 88% of stainless steel grades
- Limited formability — 25/100, worse than 78% of stainless steel grades
1.4003-QT properties
Typical room-temperature values for 1.4003-QT; 23 are specific to this condition. Other listed values are 1.4003 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4003-QT has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,450°C (2,642 °F).
Mechanical15
1.4003-QT has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 83% of stainless steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
1.4003-QT is rated for continuous service to 450°C (842 °F). It conducts heat at 29 W/m·K (16.8 BTU/hr·ft·°F), better than 97% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
1.4003-QT conducts electricity at 2.8 % IACS, better than 79% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (38/100), worse than 95% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4003-QT takes about 38 MJ of energy and emits 2.9 kg of CO₂ — less than 99% of stainless steel grades. Typical recycled content is 60%.
Manufacturability6
1.4003-QT's machinability is fair (45/100, better than 84% of stainless steel grades); weldability good (55/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4003-QT
Is 1.4003 easy to machine?
Machines like a soft low-alloy steel — better chip control than 304 but somewhat gummy; use sharp carbide, positive rake, ~120–180 m/min and generous coolant to avoid work hardening and smearing.
Can 1.4003 be welded?
Readily welded by GMAW/GTAW/SMAW with 309L/308L or matching 12Cr filler; keep heat input low and interpass ≤ 150 °C to limit HAZ grain coarsening — no pre/post-heat needed in thin sections.
Can 1.4003 be formed, bent or molded?
Cold forms and roll-bends well for a ferritic (min bend radius ≈ 1.5–2 t) but has less stretch than 304 and shows some directionality; hot work 800–1100 °C, avoid finishing below 750 °C.
What surface finishes work on 1.4003?
Takes shot-blast, brushed or 2B mill finish and paints extremely well (often supplied unpainted); can be polished but the 12Cr film dulls and tea-stains outdoors, so passivate/pickle after welding for best service life.
1.4003 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 |
|---|---|---|
| Clow carbon for weldability | ≤ 0.03 | 0.02 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1.5 | 0.9 |
| P | ≤ 0.04 | 0.03 |
| SEN 10088-2; ASTM A240 S41003 allows S ≤ 0.030 | ≤ 0.02 | 0.01 |
| Cr | 10.5 – 12.5 | 11.5 |
| NiASTM A240 S41003 allows Ni ≤ 1.50 | 0.3 – 1 | 0.5 |
| N | ≤ 0.03 | 0.02 |
| Tisome producers (3CR12Ti-type) add Ti/Nb stabilisation | ≤ 0.5 | — |
| Fe | balance | — |
1.4003-QT — frequently asked
What is 1.4003-QT used for?
1.4003-QT is typically used for mining chutes and liners, structural weldments, transport trailers and conveyor components. In short: cheapest weldable stainless structural; abrasion and corrosion compromise; paints better than 304.
What is the yield strength of 1.4003-QT?
1.4003-QT has a typical yield strength of 550 MPa (79.8 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 83% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 1.4003-QT easy to machine?
Reasonably — machinability is rated fair (45/100, better than 84% of stainless steel grades). Machines like a soft low-alloy steel — better chip control than 304 but somewhat gummy; use sharp carbide, positive rake, ~120–180 m/min and generous coolant to avoid work hardening and smearing.
Can 1.4003-QT be welded?
Yes — weldability is rated good (55/100). Readily welded by GMAW/GTAW/SMAW with 309L/308L or matching 12Cr filler; keep heat input low and interpass ≤ 150 °C to limit HAZ grain coarsening — no pre/post-heat needed in thin sections.
What surface finishes work on 1.4003-QT?
Takes shot-blast, brushed or 2B mill finish and paints extremely well (often supplied unpainted); can be polished but the 12Cr film dulls and tea-stains outdoors, so passivate/pickle after welding for best service life.
Can 1.4003-QT be formed, bent or molded?
Cold forms and roll-bends well for a ferritic (min bend radius ≈ 1.5–2 t) but has less stretch than 304 and shows some directionality; hot work 800–1100 °C, avoid finishing below 750 °C.
What is the maximum service temperature of 1.4003-QT?
1.4003-QT is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10088-1/-2 Stainless steels — X2CrNi12 (1.4003) — CEN (2014)
- ASTM A240/A240M — S41003 plate, sheet and strip — ASTM (2023)
- ASTM A1010/A1010M — high-Cr chromium alloy steel plate — ASTM (2018)
- 3CR12 / 3CR12L utility ferritic stainless steel datasheet — Columbus Stainless (2020)
- ASM Handbook Vol.1 — Properties of Stainless Steels — ASM International (1990)
- ASM Handbook Vol.16 — Machining — ASM International (1989)
- GB/T 4237 / GB/T 20878 unified stainless steel numbering (022Cr12Ni) — SAC (2015)
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.