Steel P6 NORM
Heat-treated state
AISI/SAE P6 · UNS T51606
NORM = normalized
Used to refine grain and homogenize forged or hobbed blanks before carburizing.
Values for the NORM condition
Other P6 tempers and conditions
P6 is listed in 5 conditions; see the grade overview at P6.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Pick when cavities are to be cold-hobbed with a master punch; softest achievable structure. | 350 | 585 | 25 | 165 HB | 6 % IACS |
ANNDefault Annealed | Standard stock condition for machining or cold hobbing of cavities before carburizing. | 415 | 655 | 20 | 195 HB | — |
NORMThis page Normalized | Used to refine grain and homogenize forged or hobbed blanks before carburizing. | 550 | 830 | 17 | 23 HRC | 5.5 % IACS |
Hardened & tempered | Direct oil quench without carburizing for tough holder/backing parts that need strength but not a wear surface. | 900 | 1,100 | 14 | 35 HRC | — |
Carburized, hardened & tempered | Standard service condition: hard wear-resistant case over a tough low-carbon core for impact-loaded mold parts. | 930 | 1,150 | 12 | 60 HRC | 32 W/m·K |
What is P6 NORM?
P6 NORM is P6 heat treated to NORM — used to refine grain and homogenize forged or hobbed blanks before carburizing. P6 NORM has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 71% of steel grades. Elongation at break is 17% and the elastic modulus is 205 GPa (29.7 Msi). P6 NORM 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). ANN is the default condition FabDigit quotes; NORM is available on request or by drawing note.
Limitations
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- Poor heat conductor — 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades
P6 NORM properties
Typical room-temperature values for P6 NORM; 23 are specific to this condition. Other listed values are P6 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
P6 NORM 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
P6 NORM has a yield strength of 550 MPa (79.8 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 71% of steel grades. Elongation at break is 17% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
P6 NORM is rated for continuous service to 200°C (392 °F). It conducts heat at 33 W/m·K (19.1 BTU/hr·ft·°F), worse than 80% of steel grades. Thermal expansion is 11.8 µm/m·K (6.56 µin/in·°F).
Electrical2
P6 NORM has an electrical resistivity of 3.1×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of P6 NORM takes about 34 MJ of energy and emits 2.4 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 45%.
Manufacturability8
P6 NORM's machinability is good (55/100, better than 62% of steel grades); weldability fair (50/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with P6 NORM
Is P6 easy to machine?
Machine fully in the annealed state with sharp, positive-rake carbide or HSS; the soft, gummy low-carbon Ni-Cr matrix smears, so use high feed, flood coolant and finish before carburizing.
Can P6 be welded?
Weld only annealed or normalized material with a low-carbon/low-alloy filler, preheat 200–300 °C, then re-anneal or re-carburize; welding a carburized case invites cracking.
Can P6 be formed, bent or molded?
Its main advantage is cold hobbing — cavity impressions can be pressed into the soft annealed blank, with stress-relief anneals between hobbing passes.
What surface finishes work on P6?
Case-hardened surfaces polish and texture well after tempering; add hard chrome or electroless nickel for corrosion protection since the steel rusts readily.
P6 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 |
|---|---|---|
| Clow carbon for cold hobbability | 0.05 – 0.15 | 0.1 |
| Mn | 0.35 – 0.7 | 0.5 |
| Si | 0.1 – 0.4 | 0.25 |
| Cr | 1 – 1.75 | 1.5 |
| Nicore toughness | 3.25 – 3.75 | 3.5 |
| P | ≤ 0.03 | — |
| S | ≤ 0.03 | — |
| Fe | balance | — |
P6 NORM — frequently asked
What is P6 NORM used for?
P6 NORM is typically used for carburized mold cores, impact-resistant mold inserts and die components. In short: hobbable mold steel; tough core, hard case; impact-duty P grade.
What is the yield strength of P6 NORM?
P6 NORM has a typical yield strength of 550 MPa (79.8 ksi) and a tensile strength of 830 MPa (120 ksi) — stronger than 71% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is P6 NORM easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machine fully in the annealed state with sharp, positive-rake carbide or HSS; the soft, gummy low-carbon Ni-Cr matrix smears, so use high feed, flood coolant and finish before carburizing.
Can P6 NORM be welded?
With care — weldability is rated fair (50/100). Weld only annealed or normalized material with a low-carbon/low-alloy filler, preheat 200–300 °C, then re-anneal or re-carburize; welding a carburized case invites cracking.
What surface finishes work on P6 NORM?
Case-hardened surfaces polish and texture well after tempering; add hard chrome or electroless nickel for corrosion protection since the steel rusts readily.
Can P6 NORM be formed, bent or molded?
Its main advantage is cold hobbing — cavity impressions can be pressed into the soft annealed blank, with stress-relief anneals between hobbing passes.
What is the maximum service temperature of P6 NORM?
P6 NORM 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 P6-ANN and P6 CARB-58?
ANN is the default condition — standard stock condition for machining or cold hobbing of cavities before carburizing. CARB-58: standard service condition: hard wear-resistant case over a tough low-carbon core for impact-loaded mold parts. Yield strength is 415 MPa in ANN versus 930 MPa in CARB-58.
Sources
- ASTM A681 — Alloy Tool Steels — ASTM International (2015)
- ASM Handbook Vol.1: Properties and Selection: Irons, Steels, and High-Performance Alloys (Tool Steels) — ASM International (1990)
- Tool Steels, 5th ed. (Roberts, Krauss, Kennedy) — ASM International (1998)
- UNS T51606 alloy record — SAE/ASTM Unified Numbering System (2017)
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.