Stainless Steel 1.4568 +C (Cold drawn)
Supply condition
EN 1.4568 · UNS S17700 · AISI/SAE 17-7PH · GB 07Cr17Ni7Al
Cold-rolled strip stock intended to be aged to CH900 after simple forming or coiling.
Values for the +C condition
Other 1.4568 tempers and conditions
1.4568 is listed in 6 conditions; see the grade overview at 1.4568.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+ATDefault Solution annealed | Buy in this condition when the part must be deep-drawn, roll-formed or welded first and hardened afterwards. | 275 | 895 | 35 | 165 HB | 16 W/m·K |
Condition R-100 | Intermediate martensitic state supplied when the customer will do the final 510 °C age (RH950) themselves. | 760 | 1,030 | 6 | 33 HRC | 2.1 % IACS |
Austenite conditioned 760 °C, cooled to 15 °C, aged 565 °C/90 min | The general-purpose hardened condition: best strength/toughness balance for brackets, clips and machined parts. | 1,210 | 1,310 | 9 | 42 HRC | 16 W/m·K |
+CThis page Cold drawn | Cold-rolled strip stock intended to be aged to CH900 after simple forming or coiling. | 1,310 | 1,450 | 2 | 42 HRC | — |
austenite conditioned 955 °C, refrigerated −73 °C, aged 510 °C, Rm ≥ 1450 MPa | Choose when maximum strength and elastic limit are needed from sheet, strip or bar and some ductility must remain. | 1,380 | 1,520 | 6 | 46 HRC | 16 W/m·K |
Cold rolled (Condition C) then aged 480 °C/1 h | Highest-strength strip condition for flat springs, diaphragms and shim stock where forming is minimal. | 1,655 | 1,790 | 2 | 48 HRC | — |
What is 1.4568 +C?
1.4568 +C is 1.4568 supplied in the +C condition — cold-rolled strip stock intended to be aged to CH900 after simple forming or coiling. 1.4568 +C has a yield strength of 1,310 MPa (190 ksi) and a tensile strength of 1,450 MPa (210 ksi) — stronger than 99% of stainless steel grades. Elongation at break is 2% and the elastic modulus is 200 GPa (29 Msi). 1.4568 +C has a density of 7.81 g/cm³ (0.282 lb/in³), heavier than 57% of stainless steel grades. It melts at 1,400°C (2,552 °F). +AT is the default condition FabDigit quotes; +C is available on request or by drawing note.
Advantages
- High strength — 1,310 MPa (190 ksi), better than 99% of stainless steel grades
Limitations
- Limited ductility — 2%, worse than 100% of stainless steel grades
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- Difficult to weld — 35/100, worse than 86% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
1.4568 +C properties
Typical room-temperature values for 1.4568 +C; 14 are specific to this condition. Other listed values are 1.4568 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
1.4568 +C has a density of 7.81 g/cm³ (0.282 lb/in³), heavier than 57% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
1.4568 +C has a yield strength of 1,310 MPa (190 ksi) and a tensile strength of 1,450 MPa (210 ksi) — stronger than 99% of stainless steel grades. Elongation at break is 2% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1.4568 +C is rated for continuous service to 300°C (572 °F). It conducts heat at 16.4 W/m·K (9.48 BTU/hr·ft·°F), better than 69% of stainless steel grades. Thermal expansion is 11 µm/m·K (6.11 µin/in·°F).
Electrical3
1.4568 +C conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (60/100), worse than 58% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4568 +C takes about 53 MJ of energy and emits 5 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 45%.
Manufacturability7
1.4568 +C's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability fair (35/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1.4568 +C
Is 1.4568 easy to machine?
Machine in Condition A with sharp, rigid tooling, positive rake and heavy coolant (work-hardens fast); finish machining after TH1050/RH950 needs carbide or CBN and light DOC, and allow ~0.1 % dimensional change during aging.
Can 1.4568 be welded?
GTAW, plasma and resistance welding are straightforward in Condition A with matching or 17-7 PH filler; re-solution anneal plus the full aging cycle is required to restore joint strength — avoid welding in the hardened condition.
Can 1.4568 be formed, bent or molded?
Form, draw and coil only in Condition A (or Condition C for simple bends); springback is high, and hardened TH1050/RH950/CH900 material should be considered essentially non-formable.
What surface finishes work on 1.4568?
Passivate per ASTM A967 or electropolish after descaling; no anodizing — hard chrome, electroless nickel and PVD are used for wear surfaces, with bake-out to avoid hydrogen embrittlement at ≥1450 MPa strength levels.
1.4568 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 X7CrNiAl17-7 | ≤ 0.09 | 0.07 |
| Si | ≤ 0.7 | 0.4 |
| Mn | ≤ 1 | 0.6 |
| P | ≤ 0.04 | — |
| SASTM A693 allows 0.030 max | ≤ 0.02 | — |
| Cr | 16 – 18 | 17 |
| Ni | 6.5 – 7.8 | 7.1 |
| Alprecipitation-hardening element (NiAl) | 0.75 – 1.5 | 1.15 |
| N | ≤ 0.04 | — |
| Fe | balance | — |
1.4568 +C — frequently asked
What is 1.4568 +C used for?
1.4568 +C is typically used for springs, diaphragms, aerospace structural parts and fasteners. In short: formable then spring-hard; european 17-7 PH equivalent; wide temper range.
What is the yield strength of 1.4568 +C?
1.4568 +C has a typical yield strength of 1,310 MPa (190 ksi) and a tensile strength of 1,450 MPa (210 ksi) — stronger than 99% of stainless steel grades. Strength varies by condition: see the 6 listed tempers.
Is 1.4568 +C easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Machine in Condition A with sharp, rigid tooling, positive rake and heavy coolant (work-hardens fast); finish machining after TH1050/RH950 needs carbide or CBN and light DOC, and allow ~0.1 % dimensional change during aging.
Can 1.4568 +C be welded?
With care — weldability is rated fair (35/100). GTAW, plasma and resistance welding are straightforward in Condition A with matching or 17-7 PH filler; re-solution anneal plus the full aging cycle is required to restore joint strength — avoid welding in the hardened condition.
What surface finishes work on 1.4568 +C?
Passivate per ASTM A967 or electropolish after descaling; no anodizing — hard chrome, electroless nickel and PVD are used for wear surfaces, with bake-out to avoid hydrogen embrittlement at ≥1450 MPa strength levels.
Can 1.4568 +C be formed, bent or molded?
Form, draw and coil only in Condition A (or Condition C for simple bends); springback is high, and hardened TH1050/RH950/CH900 material should be considered essentially non-formable.
What is the maximum service temperature of 1.4568 +C?
1.4568 +C is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4568 +AT and 1.4568-CH900?
+AT is the default condition — buy in this condition when the part must be deep-drawn, roll-formed or welded first and hardened afterwards. CH900: highest-strength strip condition for flat springs, diaphragms and shim stock where forming is minimal. Yield strength is 275 MPa in +AT versus 1,655 MPa in CH900.
Sources
- EN 10088-2/-3 Stainless steels — technical delivery conditions (1.4568) — CEN (2014)
- ASTM A693 — Precipitation-Hardening Stainless Steel Plate, Sheet and Strip (UNS S17700) — ASTM (2022)
- AMS 5528 / AMS 5529 — 17-7 PH sheet, strip and plate — SAE International (2018)
- 17-7 PH Stainless Steel product data bulletin — AK Steel / Cleveland-Cliffs (2016)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- GB/T 1220 / GB/T 3280 — 07Cr17Ni7Al — SAC (2007)
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.