Stainless Steel 1.4104 +QT650
Heat-treated state
EN 1.4104 · UNS S43020 · ASTM A582 · JIS SUS430F · GB Y1Cr17
+QT650 = quenched and tempered, Rm 650–850 MPa
Standard hardened-and-tempered bar condition of EN 10088-3 when moderate strength plus wear resistance is required.
Values for the +QT650 condition
Other 1.4104 tempers and conditions
1.4104 is listed in 4 conditions; see the grade overview at 1.4104.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+ADefault Annealed | Standard stock condition for high-volume automatic-lathe turning; best machinability, lowest strength. | 340 | 560 | 20 | 185 HB | — |
Cold drawn / cold worked, Rm ≥ 550 MPa | Cold-drawn ground/peeled bar: tighter tolerance and straightness with higher strength, chosen for shafts and pins machined from bar. | 500 | 650 | 12 | 215 HB | — |
+QT650This page Quenched and tempered, Rm 650–850 MPa | Standard hardened-and-tempered bar condition of EN 10088-3 when moderate strength plus wear resistance is required. | 550 | 750 | 15 | 21 HRC | — |
Hardened | Post-machining hardening (≈1000–1050 °C oil/air quench + 200–300 °C temper) for wear parts; toughness and corrosion resistance are marginal. | 950 | 1,250 | 6 | 43 HRC | — |
What is 1.4104 +QT650?
1.4104 +QT650 is 1.4104 heat treated to +QT650 — standard hardened-and-tempered bar condition of EN 10088-3 when moderate strength plus wear resistance is required. 1.4104 +QT650 has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 83% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 215 GPa (31.2 Msi). 1.4104 +QT650 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,420°C (2,588 °F). +A is the default condition FabDigit quotes; +QT650 is available on request or by drawing note.
Advantages
- Easy to machine — 68/100, better than 98% of stainless steel grades
- Conducts heat well — 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades
- High strength — 550 MPa (79.8 ksi), better than 83% of stainless steel grades
- Low embodied carbon — 3.8 kg CO₂/kg, better than 77% of stainless steel grades
Limitations
- Hard to polish — 40/100, worse than 99% of stainless steel grades
- Difficult to weld — 15/100, worse than 98% of stainless steel grades
- Needs corrosion protection — 36/100, worse than 96% of stainless steel grades
- Low fracture toughness — 45 MPa·√m (41 ksi·√in), worse than 95% of stainless steel grades
- Limited formability — 12/100, worse than 93% of stainless steel grades
1.4104 +QT650 properties
Typical room-temperature values for 1.4104 +QT650; 16 are specific to this condition. Other listed values are 1.4104 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4104 +QT650 has a density of 7.7 g/cm³ (0.278 lb/in³), lighter than 83% of stainless steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
1.4104 +QT650 has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 83% of stainless steel grades. Elongation at break is 15% and the elastic modulus is 215 GPa (31.2 Msi).
Thermal6
1.4104 +QT650 is rated for continuous service to 500°C (932 °F). It conducts heat at 25 W/m·K (14.4 BTU/hr·ft·°F), better than 93% of stainless steel grades. Thermal expansion is 10 µm/m·K (5.56 µin/in·°F).
Electrical3
1.4104 +QT650 conducts electricity at 2.5 % IACS, better than 75% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (36/100), worse than 96% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4104 +QT650 takes about 50 MJ of energy and emits 3.8 kg of CO₂ — less than 80% of stainless steel grades. Typical recycled content is 65%.
Manufacturability8
1.4104 +QT650's machinability is good (68/100, better than 98% of stainless steel grades); weldability poor (15/100); formability not recommended (12/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4104 +QT650
Is 1.4104 easy to machine?
Excellent free-cutting behaviour — high feeds on CNC/Swiss lathes, short chips, ~70 % of AISI 1212; use sharp carbide, moderate speed and sulfurised oil to avoid work-hardened smearing.
Can 1.4104 be welded?
Effectively unweldable — the high sulfur causes hot cracking and the martensitic matrix hardens in the HAZ; if unavoidable, preheat 200–300 °C, use 309-type filler and temper afterwards.
Can 1.4104 be formed, bent or molded?
Poor cold formability and low transverse ductility; bending, heading or thread rolling should be limited, roll or cut threads with generous radii, hot work 900–1150 °C followed by slow cooling/annealing.
What surface finishes work on 1.4104?
Passivate in nitric acid (ASTM A967) after machining — citric passivation works poorly on high-S grades; hard chrome or nickel plating is common for wear/corrosion upgrades, and high-gloss polishing shows sulfide pitting.
1.4104 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 X14CrMoS17 | 0.1 – 0.17 | 0.14 |
| Si | ≤ 1 | 0.5 |
| Mncombines with S as MnS chip breakers | ≤ 1.5 | 1 |
| P | ≤ 0.04 | 0.03 |
| Sfree-machining addition | 0.15 – 0.35 | 0.25 |
| Cr | 15.5 – 17.5 | 16.5 |
| Mo | 0.2 – 0.6 | 0.4 |
| Fe | balance | — |
1.4104 +QT650 — frequently asked
What is 1.4104 +QT650 used for?
1.4104 +QT650 is typically used for valve stems, screws and precision turned components. In short: free-cutting 430F bar; highest machinability in family; turned parts only, not welded.
What is the yield strength of 1.4104 +QT650?
1.4104 +QT650 has a typical yield strength of 550 MPa (79.8 ksi) and a tensile strength of 750 MPa (109 ksi) — stronger than 83% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 1.4104 +QT650 easy to machine?
Reasonably — machinability is rated good (68/100, better than 98% of stainless steel grades). Excellent free-cutting behaviour — high feeds on CNC/Swiss lathes, short chips, ~70 % of AISI 1212; use sharp carbide, moderate speed and sulfurised oil to avoid work-hardened smearing.
Can 1.4104 +QT650 be welded?
Not readily — weldability is rated poor (15/100). Effectively unweldable — the high sulfur causes hot cracking and the martensitic matrix hardens in the HAZ; if unavoidable, preheat 200–300 °C, use 309-type filler and temper afterwards.
What surface finishes work on 1.4104 +QT650?
Passivate in nitric acid (ASTM A967) after machining — citric passivation works poorly on high-S grades; hard chrome or nickel plating is common for wear/corrosion upgrades, and high-gloss polishing shows sulfide pitting.
Can 1.4104 +QT650 be formed, bent or molded?
Poor cold formability and low transverse ductility; bending, heading or thread rolling should be limited, roll or cut threads with generous radii, hot work 900–1150 °C followed by slow cooling/annealing.
What is the maximum service temperature of 1.4104 +QT650?
1.4104 +QT650 is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4104 +A and 1.4104-H?
+A is the default condition — standard stock condition for high-volume automatic-lathe turning; best machinability, lowest strength. H: post-machining hardening (≈1000–1050 °C oil/air quench + 200–300 °C temper) for wear parts; toughness and corrosion resistance are marginal. Yield strength is 340 MPa in +A versus 950 MPa in H.
Sources
- EN 10088-3 Stainless steels — semi-finished products, bars, rods, sections for general purposes — CEN (2014)
- EN 10088-1 Stainless steels — List of stainless steels (physical properties) — CEN (2014)
- ASTM A582/A582M Free-Machining Stainless Steel Bars (Type 430F) — ASTM (2021)
- GB/T 1220 (Y1Cr17) — SAC (2007)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Free-machining stainless bar 1.4104/430F data sheet — Sandvik / Deutsche Edelstahlwerke (typical bar data) (2020)
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.