Stainless Steel 1.4112 QT-56
Heat-treated state
EN 1.4112
QT-56 = hardened + tempered ~200 °C
Workhorse condition for kitchen/industrial blades, surgical instruments and wear parts — good hardness with usable toughness.
Values for the QT-56 condition
Other 1.4112 tempers and conditions
1.4112 is listed in 7 conditions; see the grade overview at 1.4112.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+ADefault Annealed | Standard stock condition for bar, wire and blade stock — machine or blank first, then harden. | 470 | 800 | 16 | 24 HRC | — |
Annealed and cold drawn bar/wire | Pick for close-tolerance ground/drawn bar and blade wire that will still be hardened after machining. | 650 | 900 | 10 | 28 HRC | 2.7 % IACS |
Hardened + tempered ~300 °C | Higher-temper condition when a bit more toughness is wanted in valve parts or heavy tooling; corrosion resistance already reduced. | 1,500 | 1,750 | 3 | 52 HRC | — |
Hardened + tempered 500–550 °C | Only for parts needing higher temper resistance (e.g. warm-working tools); avoid where corrosion resistance matters. | 1,620 | 1,850 | 2 | 54 HRC | 2.5 % IACS |
QT-56This page Hardened + tempered ~200 °C | Workhorse condition for kitchen/industrial blades, surgical instruments and wear parts — good hardness with usable toughness. | 1,700 | 1,900 | 2.5 | 56 HRC | — |
Hardened + tempered 150–180 °C | Maximum practical hardness for razor blades, bearing races and edge-retention-critical cutlery; toughness is minimal. | 1,850 | 2,050 | 1.5 | 59 HRC | — |
Hardened + deep freeze + double temper | Choose when retained austenite must be minimised for dimensional stability — precision bearings, gauges and premium knives. | 1,900 | 2,100 | 1.2 | 60 HRC | — |
What is 1.4112 QT-56?
1.4112 QT-56 is 1.4112 heat treated to QT-56 — workhorse condition for kitchen/industrial blades, surgical instruments and wear parts — good hardness with usable toughness. 1.4112 QT-56 has a yield strength of 1,700 MPa (247 ksi) and a tensile strength of 1,900 MPa (276 ksi) — stronger than 100% of stainless steel grades. Elongation at break is 2.5% and the elastic modulus is 215 GPa (31.2 Msi). 1.4112 QT-56 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,400°C (2,552 °F). +A is the default condition FabDigit quotes; QT-56 is available on request or by drawing note.
Advantages
- High strength — 1,700 MPa (247 ksi), better than 100% of stainless steel grades
- Polishes to a fine finish — 88/100, better than 100% of stainless steel grades
- High electrical conductivity — 2.7 % IACS, better than 78% of stainless steel grades
Limitations
- Limited ductility — 2.5%, worse than 100% of stainless steel grades
- Low fracture toughness — 20 MPa·√m (18.2 ksi·√in), worse than 100% of stainless steel grades
- Limited service temperature — 200°C (392 °F), worse than 100% of stainless steel grades
- Difficult to machine — 5/100, worse than 100% of stainless steel grades
- Difficult to weld — 15/100, worse than 98% of stainless steel grades
1.4112 QT-56 properties
Typical room-temperature values for 1.4112 QT-56; 14 are specific to this condition. Other listed values are 1.4112 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4112 QT-56 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
1.4112 QT-56 has a yield strength of 1,700 MPa (247 ksi) and a tensile strength of 1,900 MPa (276 ksi) — stronger than 100% of stainless steel grades. Elongation at break is 2.5% and the elastic modulus is 215 GPa (31.2 Msi).
Thermal6
1.4112 QT-56 is rated for continuous service to 200°C (392 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 10.4 µm/m·K (5.78 µin/in·°F).
Electrical3
1.4112 QT-56 conducts electricity at 2.7 % IACS, better than 78% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (47/100), worse than 81% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4112 QT-56 takes about 58 MJ of energy and emits 4.8 kg of CO₂ — more than 66% of stainless steel grades. Typical recycled content is 50%.
Manufacturability8
1.4112 QT-56's machinability is not recommended (5/100, worse than 100% of stainless steel grades); weldability poor (15/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4112 QT-56
Is 1.4112 easy to machine?
Machine only in the annealed condition with sharp, rigid setups, low speed and heavy positive-rake carbide (approx. 40 % of AISI 1212); after hardening, grinding or EDM is the only realistic route.
Can 1.4112 be welded?
Essentially not weldable for structural joints — if unavoidable, preheat 250–300 °C, use matching or austenitic filler and temper immediately; high risk of quench cracking from the 0.9 %C content.
Can 1.4112 be formed, bent or molded?
Cold forming is limited to gentle bends on thin annealed strip; hot work at 1050–850 °C followed by slow cooling and full spheroidise anneal.
What surface finishes work on 1.4112?
Passivate per ASTM A967 or electropolish after final grinding; mirror polishing is excellent in the hardened state, and PVD (TiN/CrN) at ≤180 °C or hard chrome can be applied without over-tempering.
1.4112 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 |
|---|---|---|
| CEN 10088-3 X90CrMoV18 | 0.85 – 0.95 | 0.9 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1 | 0.5 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 17 – 19 | 18 |
| Mo | 0.9 – 1.3 | 1.1 |
| V | 0.07 – 0.12 | 0.1 |
| Fe | balance | — |
1.4112 QT-56 — frequently asked
What is 1.4112 QT-56 used for?
1.4112 QT-56 is typically used for knives, surgical instruments, bearings and cutting tools. In short: 440B-class hardness, up to 59 HRC; vanadium carbides for edge retention; tool-grade, non-weldable stainless.
What is the yield strength of 1.4112 QT-56?
1.4112 QT-56 has a typical yield strength of 1,700 MPa (247 ksi) and a tensile strength of 1,900 MPa (276 ksi) — stronger than 100% of stainless steel grades. Strength varies by condition: see the 7 listed tempers.
Is 1.4112 QT-56 easy to machine?
Not especially — machinability is rated not recommended (5/100, worse than 100% of stainless steel grades). Machine only in the annealed condition with sharp, rigid setups, low speed and heavy positive-rake carbide (approx. 40 % of AISI 1212); after hardening, grinding or EDM is the only realistic route.
Can 1.4112 QT-56 be welded?
Not readily — weldability is rated poor (15/100). Essentially not weldable for structural joints — if unavoidable, preheat 250–300 °C, use matching or austenitic filler and temper immediately; high risk of quench cracking from the 0.9 %C content.
What surface finishes work on 1.4112 QT-56?
Passivate per ASTM A967 or electropolish after final grinding; mirror polishing is excellent in the hardened state, and PVD (TiN/CrN) at ≤180 °C or hard chrome can be applied without over-tempering.
Can 1.4112 QT-56 be formed, bent or molded?
Cold forming is limited to gentle bends on thin annealed strip; hot work at 1050–850 °C followed by slow cooling and full spheroidise anneal.
What is the maximum service temperature of 1.4112 QT-56?
1.4112 QT-56 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4112 +A and 1.4112 QT-CRYO?
+A is the default condition — standard stock condition for bar, wire and blade stock — machine or blank first, then harden. QT-CRYO: choose when retained austenite must be minimised for dimensional stability — precision bearings, gauges and premium knives. Yield strength is 470 MPa in +A versus 1,900 MPa in QT-CRYO.
Sources
- EN 10088-3 Stainless steels — semi-finished products, bars, rods, wire — CEN (2014)
- GB/T 1220 (9Cr18MoV) — SAC (2007)
- ASTM A276 / A756 Stainless Steel Bars and Shapes (Type 440B) — ASTM (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
- Böhler N685 / martensitic stainless knife steel datasheet — voestalpine Böhler Edelstahl (2021)
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.