Steel 38Mn6 +AR (Hot rolled)
Heat-treated state
EN 38Mn6
Cheapest mill condition for stock that will be forged, machined and heat treated by the user; properties are not guaranteed.
Values for the +AR condition
Other 38Mn6 tempers and conditions
38Mn6 is listed in 5 conditions; see the grade overview at 38Mn6.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Choose for maximum machinability and cold-working ability before final hardening; hardness capped at 217 HB per EN 10083-2. | 340 | 620 | 21 | 190 HB | — |
Normalized | Choose for a uniform fine-grained pearlitic structure with balanced strength and toughness where full Q&T is not required. | 390 | 680 | 18 | 205 HB | — |
+ARThis page Hot rolled | Cheapest mill condition for stock that will be forged, machined and heat treated by the user; properties are not guaranteed. | 400 | 700 | 17 | 210 HB | — |
+QTDefault Quenched and tempered | Standard supply condition for shafts and axles: oil quench from ~850 °C and temper 550–660 °C for 700–1000 MPa tensile with good toughness. | 510 | 800 | 16 | 22 HRC | — |
Cold drawn | Choose bright cold-drawn bar for tight tolerance and better surface where drawn strength is sufficient and no further heat treatment is planned. | 620 | 740 | 10 | 220 HB | — |
What is 38Mn6 +AR?
38Mn6 +AR is 38Mn6 heat treated to +AR — cheapest mill condition for stock that will be forged, machined and heat treated by the user; properties are not guaranteed. 38Mn6 +AR has a yield strength of 400 MPa (58 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 60% of steel grades. Elongation at break is 17% and the elastic modulus is 210 GPa (30.5 Msi). 38Mn6 +AR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F). +QT is the default condition FabDigit quotes; +AR is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
Limitations
- Low fracture toughness — 65 MPa·√m (59.2 ksi·√in), worse than 75% of steel grades
38Mn6 +AR properties
Typical room-temperature values for 38Mn6 +AR; 13 are specific to this condition. Other listed values are 38Mn6 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
38Mn6 +AR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
38Mn6 +AR has a yield strength of 400 MPa (58 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 60% of steel grades. Elongation at break is 17% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
38Mn6 +AR is rated for continuous service to 350°C (662 °F). It conducts heat at 43 W/m·K (24.8 BTU/hr·ft·°F), better than 51% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
38Mn6 +AR conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 38Mn6 +AR takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 96% of steel grades. Typical recycled content is 30%.
Manufacturability6
38Mn6 +AR's machinability is good (56/100, better than 71% of steel grades); weldability fair (45/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 38Mn6 +AR
Is 38Mn6 easy to machine?
Machine in the annealed or normalized condition where possible; in +QT at ~240 HB use coated carbide, 120–180 m/min, rigid setups — chips are stringy so use chipbreakers or a resulphurized variant.
Can 38Mn6 be welded?
Carbon equivalent ≈0.6–0.7, so preheat 200–300 °C, use low-hydrogen consumables and stress-relieve/temper afterwards; welding a finished Q&T part locally destroys the temper.
Can 38Mn6 be formed, bent or molded?
Hot forge 1150–850 °C then normalize; cold forming only in the annealed condition with generous bend radii, as the Mn content raises work hardening.
What surface finishes work on 38Mn6?
No corrosion resistance of its own — protect with phosphating + oil, zinc plate, black oxide, nitriding or paint; induction hardening of journals to 50–55 HRC is common and it takes a good ground/polished finish.
38Mn6 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 10083-2 | 0.34 – 0.42 | 0.38 |
| Si | ≤ 0.4 | 0.25 |
| Mngives the hardenability advantage | 1.3 – 1.65 | 1.5 |
| P | ≤ 0.04 | — |
| Smax; free-cutting variants raise S | ≤ 0.04 | — |
| Crresidual | ≤ 0.4 | — |
| Moresidual | ≤ 0.1 | — |
| Niresidual; Cr+Mo+Ni ≤ 0.63 | ≤ 0.4 | — |
| Fe | balance | — |
38Mn6 +AR — frequently asked
What is 38Mn6 +AR used for?
38Mn6 +AR is typically used for shafts, axles, gears and machine structural components. In short: better hardenability than C40; 800 MPa in +QT; limited weldability.
What is the yield strength of 38Mn6 +AR?
38Mn6 +AR has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is 38Mn6 +AR easy to machine?
Reasonably — machinability is rated good (56/100, better than 71% of steel grades). Machine in the annealed or normalized condition where possible; in +QT at ~240 HB use coated carbide, 120–180 m/min, rigid setups — chips are stringy so use chipbreakers or a resulphurized variant.
Can 38Mn6 +AR be welded?
With care — weldability is rated fair (45/100). Carbon equivalent ≈0.6–0.7, so preheat 200–300 °C, use low-hydrogen consumables and stress-relieve/temper afterwards; welding a finished Q&T part locally destroys the temper.
What surface finishes work on 38Mn6 +AR?
No corrosion resistance of its own — protect with phosphating + oil, zinc plate, black oxide, nitriding or paint; induction hardening of journals to 50–55 HRC is common and it takes a good ground/polished finish.
Can 38Mn6 +AR be formed, bent or molded?
Hot forge 1150–850 °C then normalize; cold forming only in the annealed condition with generous bend radii, as the Mn content raises work hardening.
What is the maximum service temperature of 38Mn6 +AR?
38Mn6 +AR is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10083-2 Steels for quenching and tempering — Non-alloy steels — CEN (2006)
- SAE J403 / J404 Chemical compositions of carbon and alloy steels (1541, 1345) — SAE International (2014)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Machinery's Handbook, 31st ed. — machinability ratings — Industrial Press (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.