Stainless Steel 1.4028 +QT850
Heat-treated state
EN 1.4028 · GB 3Cr13
+QT850 = quenched and tempered, Rm 850–1000 MPa
Pick the next quench-and-temper step up (Rm 850–1000 MPa) for loaded shafts and pump or valve parts, accepting 12% elongation and machinability down to 36.
Values for the +QT850 condition
Other 1.4028 tempers and conditions
1.4028 is listed in 7 conditions; see the grade overview at 1.4028.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+ADefault Annealed | Pick the soft annealed delivery condition (≤235 HB) for machining and cold forming ahead of customer hardening; strength is capped near 740 MPa tensile with 17% elongation. | 450 | 740 | 17 | 15 HRC | — |
Cold drawn | Choose annealed-then-cold-drawn bar for turned parts needing tight diameter tolerance and straightness; drawing lifts yield to 620 MPa but cuts formability and elongation to 12%. | 620 | 820 | 12 | 24 HRC | 3.1 % IACS |
Quenched and tempered, Rm 800–950 MPa | Choose this quenched and tempered EN grade (Rm 800–950 MPa) for shafts, valve stems and fasteners needing balanced toughness and medium strength; welding remains difficult at 265 HB. | 650 | 870 | 14 | 26 HRC | — |
Cold rolled hard strip | Use cold rolled hard strip for blanking blades and shims that are hardened after stamping; 900 MPa tensile comes with 8% elongation and limited bending capability. | 700 | 900 | 8 | 28 HRC | 3.1 % IACS |
+QT850This page Quenched and tempered, Rm 850–1000 MPa | Pick the next quench-and-temper step up (Rm 850–1000 MPa) for loaded shafts and pump or valve parts, accepting 12% elongation and machinability down to 36. | 700 | 920 | 12 | 30 HRC | — |
Hardened and tempered ~400 °C | Choose hardening with a tempering near 400 °C (~46–48 HRC) for die and shaft parts needing a hardness-toughness compromise; avoid tempering in the 450–550 °C embrittlement range. | 1,300 | 1,550 | 6 | 47 HRC | — |
Hardened 1000–1050 °C, tempered 180–250 °C | Use hardening at 1000–1050 °C with a 180–250 °C temper (~52–54 HRC) for knives, surgical blades and wear parts; toughness drops to 3% elongation and machining is nearly impossible. | 1,500 | 1,800 | 3 | 53 HRC | — |
What is 1.4028 +QT850?
1.4028 +QT850 is 1.4028 heat treated to +QT850 — pick the next quench-and-temper step up (Rm 850–1000 MPa) for loaded shafts and pump or valve parts, accepting 12% elongation and machinability down to 36. 1.4028 +QT850 has a yield strength of 700 MPa (102 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 92% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 215 GPa (31.2 Msi). 1.4028 +QT850 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). +A is the default condition FabDigit quotes; +QT850 is available on request or by drawing note.
Advantages
- Conducts heat well — 30 W/m·K (17.3 BTU/hr·ft·°F), better than 99% of stainless steel grades
- High electrical conductivity — 3.1 % IACS, better than 99% of stainless steel grades
- High strength — 700 MPa (102 ksi), better than 92% of stainless steel grades
- Polishes to a fine finish — 80/100, better than 89% of stainless steel grades
Limitations
- Limited ductility — 12%, worse than 95% of stainless steel grades
- Difficult to weld — 20/100, worse than 95% of stainless steel grades
- Needs corrosion protection — 46/100, worse than 82% of stainless steel grades
1.4028 +QT850 properties
Typical room-temperature values for 1.4028 +QT850; 17 are specific to this condition. Other listed values are 1.4028 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4028 +QT850 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
1.4028 +QT850 has a yield strength of 700 MPa (102 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 92% of stainless steel grades. Elongation at break is 12% and the elastic modulus is 215 GPa (31.2 Msi).
Thermal6
1.4028 +QT850 is rated for continuous service to 480°C (896 °F). It conducts heat at 30 W/m·K (17.3 BTU/hr·ft·°F), better than 99% of stainless steel grades. Thermal expansion is 10.5 µm/m·K (5.83 µin/in·°F).
Electrical3
1.4028 +QT850 conducts electricity at 3.1 % IACS, better than 99% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (46/100), worse than 82% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4028 +QT850 takes about 48 MJ of energy and emits 4 kg of CO₂ — less than 85% of stainless steel grades. Typical recycled content is 60%.
Manufacturability8
1.4028 +QT850's machinability is fair (36/100, better than 57% of stainless steel grades); weldability poor (20/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4028 +QT850
Is 1.4028 easy to machine?
Machine annealed with sharp cobalt HSS or coated carbide at reduced speeds and with plenty of coolant. Above 45 HRC the grade is essentially grind-only, or turned with CBN.
Can 1.4028 be welded?
Weldability is poor: preheat to 150–300 °C, use low-hydrogen matching or austenitic filler, and temper immediately at 700–750 °C to prevent cold cracking and martensite embrittlement.
Can 1.4028 be formed, bent or molded?
Only mild cold bending, blanking and roll forming in the annealed condition; re-harden and temper afterwards to restore properties. Hot forming range is approximately 1100–850 °C followed by slow cooling.
What surface finishes work on 1.4028?
After quench and temper it polishes to a mirror finish and should be passivated for best corrosion resistance. PVD (TiN/CrN) or hard chrome raises wear life; the grade cannot be anodised.
1.4028 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 X30Cr13 | 0.26 – 0.35 | 0.3 |
| Si | ≤ 1 | 0.4 |
| Mn | ≤ 1 | 0.5 |
| P | ≤ 0.04 | — |
| Sfree-machining variant 1.4029 has S 0.15–0.35 | ≤ 0.03 | — |
| Cr | 12 – 14 | 13 |
| Niresidual, some mill specs | ≤ 0.5 | — |
| Moresidual | ≤ 0.5 | — |
| Fe | balance | — |
1.4028 +QT850 — frequently asked
What is 1.4028 +QT850 used for?
1.4028 +QT850 is typically used for knives, surgical instruments, scissors and valve seats. In short: 52–54 HRC after hardening; cutlery-grade 13% Cr; poor weldability.
What is the yield strength of 1.4028 +QT850?
1.4028 +QT850 has a typical yield strength of 700 MPa (102 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 92% of stainless steel grades. Strength varies by condition: see the 7 listed tempers.
Is 1.4028 +QT850 easy to machine?
Not especially — machinability is rated fair (36/100, better than 57% of stainless steel grades). Machine annealed with sharp cobalt HSS or coated carbide at reduced speeds and with plenty of coolant. Above 45 HRC the grade is essentially grind-only, or turned with CBN.
Can 1.4028 +QT850 be welded?
Not readily — weldability is rated poor (20/100). Weldability is poor: preheat to 150–300 °C, use low-hydrogen matching or austenitic filler, and temper immediately at 700–750 °C to prevent cold cracking and martensite embrittlement.
What surface finishes work on 1.4028 +QT850?
After quench and temper it polishes to a mirror finish and should be passivated for best corrosion resistance. PVD (TiN/CrN) or hard chrome raises wear life; the grade cannot be anodised.
Can 1.4028 +QT850 be formed, bent or molded?
Only mild cold bending, blanking and roll forming in the annealed condition; re-harden and temper afterwards to restore properties. Hot forming range is approximately 1100–850 °C followed by slow cooling.
What is the maximum service temperature of 1.4028 +QT850?
1.4028 +QT850 is rated for continuous use to about 480°C (896 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10088-3 Stainless steels – Semi-finished products, bars, rods — CEN (2014)
- EN 10088-1 Stainless steels – List of stainless steels — CEN (2014)
- GB/T 1220 (3Cr13/30Cr13) — SAC (2007)
- JIS G 4303 Stainless steel bars (SUS420J2) — JSA (2021)
- ASM Handbook Vol.1: Properties and Selection – Irons, Steels — ASM International (1990)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- Martensitic stainless bar/strip datasheets (X30Cr13 / 420) — Outokumpu / Böhler / Sandvik (2022)
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.