Steel 30MoB1
EN 30MoB1
30MoB1 (1.5408) is a boron-treated molybdenum steel that buys hardenability at low alloy content, aimed at cold-formed fasteners and medium-strength shafts.
Reference datasheet — 30MoB1 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the +AC+C condition
30MoB1 tempers and conditions
30MoB1 is supplied in 9 conditions, soft to hard. +AC+C is the default FabDigit quotes; the values on this page are for it.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Pick for severe multi-station cold heading and cold extrusion — lowest flow stress and best die life. | 320 | 520 | 23 | 152 HB | — |
Annealed | General soft-annealed bar for machining or light upsetting before hardening. | 340 | 570 | 20 | 165 HB | — |
Hot rolled | Mill as-rolled coil, the cheapest input when the fastener maker does its own spheroidizing. | 410 | 660 | 17 | 195 HB | — |
+AC+CDefault Spheroidized and cold drawn to size | The standard cold-heading wire delivery condition: drawn to gauge with a phosphate/lubricant coating, ready to head and then quench & temper. | 530 | 620 | 11 | 185 HB | — |
Cold drawn | Straight, size-accurate bar for machined shafts that will be hardened afterwards. | 610 | 710 | 8 | 210 HB | — |
+QT to property class 8.8 | Fastener heat treatment for class 8.8 bolts — tempered high for maximum ductility and low hydrogen-embrittlement risk. | 720 | 900 | 13 | 27 HRC | — |
Quenched and tempered | Balanced strength/toughness condition for medium-strength shafts, pins and studs up to ~20 mm section. | 850 | 1,000 | 14 | 31 HRC | — |
+QT to property class 10.9 | Main commercial reason for the grade: 10.9 bolts and wheel studs at lower alloy cost than 42CrMo4. | 990 | 1,100 | 10 | 34 HRC | — |
Guaranteed hardenability, supplied/used in the hardened (quenched +… | Order +H when the Jominy band matters; in the as-hardened (oil/water quench + 180–250 °C temper) state it gives maximum hardness and wear resistance but low toughness. | 1,250 | 1,550 | 8 | 46 HRC | — |
What is 30MoB1?
30MoB1 (1.5408) is a boron-treated molybdenum steel that buys hardenability at low alloy content, aimed at cold-formed fasteners and medium-strength shafts. In the default condition it gives about 530 MPa yield, 620 MPa tensile, 11 % elongation and 185 HB (90 HRB), and it is also supplied as +QT 8.8 and +QT 10.9 fastener conditions in wire and bar. Cold formability (60) and machinability (58) are reasonable, but the boron plus 0.25 Mo makes the HAZ air-hardening, service is limited to 300 °C and there is no corrosion resistance. 30MnB4 or 34Cr4 are the usual substitutes when availability or higher tempering resistance matters. 30MoB1 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,430°C (2,606 °F). 30MoB1 has a yield strength of 530 MPa (76.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 69% of steel grades. Elongation at break is 11% and the elastic modulus is 210 GPa (30.5 Msi).
What is 30MoB1 used for?
- fasteners
- shafts
- structural bolts
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
Limitations
- Limited ductility — 11%, worse than 89% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
30MoB1 properties
Typical room-temperature values for 30MoB1-+AC+C; bars are the position among steel grades.
Physical3
30MoB1 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,430°C (2,606 °F).
Mechanical14
30MoB1 has a yield strength of 530 MPa (76.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 69% of steel grades. Elongation at break is 11% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
30MoB1 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 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
30MoB1 conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of 30MoB1 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
30MoB1's machinability is good (58/100, better than 75% of steel grades); weldability fair (50/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. 30MoB1 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 30MoB1
Is 30MoB1 easy to machine?
Machines like a 0.30 % C low-alloy steel (~60–65 % of AISI 1212) in +AC/+AC+C; spheroidized structure is gummy, so use sharp coated carbide, positive rake and good chip breaking, and machine before hardening wherever possible.
Can 30MoB1 be welded?
Weldable with low-hydrogen consumables but boron plus 0.25 Mo make the HAZ air-hardening: preheat 150–250 °C, control interpass, and post-weld temper; welding after Q&T destroys the fastener strength class.
Can 30MoB1 be formed, bent or molded?
Designed for cold heading and cold extrusion in the +AC condition with phosphate+soap or polymer lubricant; upsetting ratios typical of 30MnB4-class steel are achievable, hot forging 1100–1200 °C, finish above 900 °C.
30MoB1 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 | 0.27 – 0.33 | 0.3 |
| Silow Si for cold heading | ≤ 0.3 | 0.15 |
| Mn | 0.6 – 0.9 | 0.75 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Motemper-resistance and hardenability | 0.2 – 0.3 | 0.25 |
| Beffective (soluble) boron; needs Ti/Al nitrogen fixing | 8×10⁻⁴ – 0.01 | 0 |
| Algrain refinement / N fixing | 0.02 – 0.06 | 0.04 |
| Tioptional, to protect boron from N | ≤ 0.05 | 0.03 |
| Crresidual | ≤ 0.3 | 0.1 |
| Niresidual | ≤ 0.3 | 0.08 |
| Curesidual | ≤ 0.25 | 0.1 |
| Fe | balance |
What surface finishes work on 30MoB1?
No anodizing — protect with zinc or zinc-nickel electroplate (bake 200 °C ≥4 h to de-embrittle parts ≥1000 MPa), zinc-flake (Dacromet/Geomet) for 10.9 fasteners, or phosphate and oil.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel 30MoB1 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.5408
How much does 30MoB1 cost?
30MoB1 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
30MoB1 — frequently asked
What is 30MoB1 used for?
30MoB1 is typically used for fasteners, shafts and structural bolts. In short: boron hardenability, low alloy cost; reaches 8.8 and 10.9 classes; cold-heading fastener steel.
What is the yield strength of 30MoB1?
30MoB1 has a typical yield strength of 530 MPa (76.9 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 69% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is 30MoB1 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machines like a 0.30 % C low-alloy steel (~60–65 % of AISI 1212) in +AC/+AC+C; spheroidized structure is gummy, so use sharp coated carbide, positive rake and good chip breaking, and machine before hardening wherever possible.
Can 30MoB1 be welded?
With care — weldability is rated fair (50/100). Weldable with low-hydrogen consumables but boron plus 0.25 Mo make the HAZ air-hardening: preheat 150–250 °C, control interpass, and post-weld temper; welding after Q&T destroys the fastener strength class.
What surface finishes work on 30MoB1?
No anodizing — protect with zinc or zinc-nickel electroplate (bake 200 °C ≥4 h to de-embrittle parts ≥1000 MPa), zinc-flake (Dacromet/Geomet) for 10.9 fasteners, or phosphate and oil.
Can 30MoB1 be formed, bent or molded?
Designed for cold heading and cold extrusion in the +AC condition with phosphate+soap or polymer lubricant; upsetting ratios typical of 30MnB4-class steel are achievable, hot forging 1100–1200 °C, finish above 900 °C.
What is the maximum service temperature of 30MoB1?
30MoB1 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.
How much does 30MoB1 cost?
30MoB1 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- EN 10263-4 Steel rod, bars and wire for cold heading and cold extrusion — Part 4: quench and temper steels — CEN (2017)
- EN ISO 898-1 Mechanical properties of fasteners — bolts, screws and studs — ISO (2013)
- EN 10083-3 Steels for quenching and tempering — alloy steels — CEN (2006)
- ASM Handbook Vol. 1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Stahlschlüssel / Key to Steel — material 1.5408 — Verlag Stahlschlüssel Wegst (2019)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.