Steel 17CrS3 +FP
Heat-treated state
EN 17CrS3
+FP = treated to ferrite-pearlite structure
Hot-rolled/normalized-type bar with a defined ferrite-pearlite structure and hardness band — the usual starting stock for hot forging and for parts machined from hot-rolled bar.
Values for the +FP condition
Other 17CrS3 tempers and conditions
17CrS3 is listed in 5 conditions; see the grade overview at 17CrS3.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Softest condition — pick it for cold extrusion, cold heading and heavy deep-hole machining before carburizing. | 310 | 500 | 23 | 155 HB | — |
+FPThis page Treated to ferrite-pearlite structure | Hot-rolled/normalized-type bar with a defined ferrite-pearlite structure and hardness band — the usual starting stock for hot forging and for parts machined from hot-rolled bar. | 350 | 560 | 19 | 165 HB | — |
Hot rolled with specified (standard) hardenability band, Jominy… | Order this when the carburizing shop needs a guaranteed Jominy end-quench band so case/core hardness after quenching is reproducible. | 370 | 600 | 17 | 175 HB | — |
+AC+CDefault Spheroidize annealed then cold drawn | Standard bright bar for CNC/cam automatic lathes: good size tolerance, straightness and chip control before carburizing. | 490 | 620 | 10 | 190 HB | — |
Carburized, quenched and low-temperature tempered (finished part condition) | Final in-service condition: hard wear-resistant case with a tough, moderately strong core — for small pins, bushes and gears. | 560 | 850 | 11 | 60 HRC | — |
What is 17CrS3 +FP?
17CrS3 +FP is 17CrS3 heat treated to +FP — hot-rolled/normalized-type bar with a defined ferrite-pearlite structure and hardness band — the usual starting stock for hot forging and for parts machined from hot-rolled bar. 17CrS3 +FP has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 74% of steel grades. Elongation at break is 19% and the elastic modulus is 210 GPa (30.5 Msi). 17CrS3 +FP has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). +AC+C is the default condition FabDigit quotes; +FP is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
17CrS3 +FP properties
Typical room-temperature values for 17CrS3 +FP; 15 are specific to this condition. Other listed values are 17CrS3 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
17CrS3 +FP has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
17CrS3 +FP has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 74% of steel grades. Elongation at break is 19% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
17CrS3 +FP is rated for continuous service to 300°C (572 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
17CrS3 +FP conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.
Sustainability4
Producing a kilogram of 17CrS3 +FP takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
17CrS3 +FP's machinability is good (60/100, better than 83% of steel grades); weldability poor (32/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 17CrS3 +FP
Is 17CrS3 easy to machine?
Excellent for automatics — MnS breaks chips and lubricates the cutting edge; run ~20–30 % faster than 17Cr3, carbide inserts with light positive geometry, keep coolant flow to flush fine chips.
Can 17CrS3 be welded?
Avoid structural welding: sulfur promotes hot cracking; if unavoidable, preheat 150–250 °C, use low-hydrogen consumables and post-weld stress relieve, and never weld carburized surfaces.
Can 17CrS3 be formed, bent or molded?
Cold heading and cold extrusion only in the +AC condition and with reduced severity — sulfide stringers cut transverse ductility; hot forge 1100–850 °C then normalize/anneal before machining.
What surface finishes work on 17CrS3?
Not anodizable; protect with zinc or zinc-nickel plating, phosphating, black oxide or oil. Case-hardened surfaces polish and hard-grind well, but MnS pits limit mirror finishes.
17CrS3 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 |
|---|---|---|
| C | 0.14 – 0.2 | 0.17 |
| Si | ≤ 0.4 | 0.25 |
| Mn | 0.6 – 0.9 | 0.75 |
| P | ≤ 0.03 | — |
| Sdeliberate resulfurizing for free machining | 0.02 – 0.04 | 0.03 |
| Cr | 0.7 – 1 | 0.85 |
| Fe | balance | — |
17CrS3 +FP — frequently asked
What is 17CrS3 +FP used for?
17CrS3 +FP is typically used for small gears, pins and case-hardened fasteners. In short: best-machining case-hardening steel; free-cutting 17Cr3 variant; not for structural welds.
What is the yield strength of 17CrS3 +FP?
17CrS3 +FP has a typical yield strength of 350 MPa (50.8 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 74% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is 17CrS3 +FP easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Excellent for automatics — MnS breaks chips and lubricates the cutting edge; run ~20–30 % faster than 17Cr3, carbide inserts with light positive geometry, keep coolant flow to flush fine chips.
Can 17CrS3 +FP be welded?
Not readily — weldability is rated poor (32/100). Avoid structural welding: sulfur promotes hot cracking; if unavoidable, preheat 150–250 °C, use low-hydrogen consumables and post-weld stress relieve, and never weld carburized surfaces.
What surface finishes work on 17CrS3 +FP?
Not anodizable; protect with zinc or zinc-nickel plating, phosphating, black oxide or oil. Case-hardened surfaces polish and hard-grind well, but MnS pits limit mirror finishes.
Can 17CrS3 +FP be formed, bent or molded?
Cold heading and cold extrusion only in the +AC condition and with reduced severity — sulfide stringers cut transverse ductility; hot forge 1100–850 °C then normalize/anneal before machining.
What is the maximum service temperature of 17CrS3 +FP?
17CrS3 +FP 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.
Sources
- EN 10084 — Case hardening steels: technical delivery conditions — CEN (2008)
- EN 10277 — Bright steel products: technical delivery conditions — CEN (2018)
- EN 10027-2 — Designation systems for steels: numerical system (1.7014) — CEN (2015)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- Stahlschlüssel (Key to Steel) — Verlag Stahlschlüssel Wegst (2019)
- European bright-bar producer datasheets for 17Cr3 / 17CrS3 case-hardening steel — various mills (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.