Steel 17B2
EN 17B2
17B2 (1.5502) is a low-carbon boron steel for hardenable fasteners, supplied +U, +AC, +AC+C, +U+C or +H, and fills the same role as 15B2 with slightly higher carbon.
Reference datasheet — 17B2 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
17B2 tempers and conditions
17B2 is supplied in 5 conditions, soft to hard. +AC+C is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Choose when maximum cold-heading/upsetting ductility is needed before drawing or multi-station forming. | 265 | 430 | 28 | 120 HB | — |
Hot rolled | Cheapest starting stock for re-heating, forging or subsequent annealing and drawing; not for direct heavy cold heading. | 320 | 490 | 22 | 145 HB | — |
+AC+CDefault Spheroidize annealed then cold drawn | Standard cold-heading wire condition: good size/surface control with enough residual ductility for bolt and screw heading. | 400 | 520 | 13 | 150 HB | — |
Cold drawn from untreated (hot rolled) stock | Economical drawn wire/bar for light cold forming, rivets and turned parts where full heading ductility is not required. | 470 | 580 | 10 | 170 HB | — |
Hardened and tempered | Final strength condition for headed fasteners after forming: boron gives full through-hardening in small diameters, then temper to 26–32 HRC. | 700 | 850 | 13 | 29 HRC | — |
What is 17B2?
17B2 (1.5502) is a low-carbon boron steel for hardenable fasteners, supplied +U, +AC, +AC+C, +U+C or +H, and fills the same role as 15B2 with slightly higher carbon. The default condition gives 400 MPa yield, 520 MPa tensile, 13% elongation and 150 HB (80 HRB), with a formability score of 78/100 for cold-headed bolts, fasteners and upset parts made from drawn wire. Weldability is moderate (70/100) because boron sharply raises HAZ hardenability, and the steel has no corrosion resistance, so plating or zinc-flake coating is required. 15B2 is the more formable, lower-carbon alternative. 17B2 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F). 17B2 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 60% of steel grades. Elongation at break is 13% and the elastic modulus is 207 GPa (30 Msi).
What is 17B2 used for?
- bolts
- fasteners
- cold-formed parts
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Forms and bends easily — 78/100, better than 91% of steel grades
- High electrical conductivity — 9.5 % IACS, better than 75% of steel grades
Limitations
- Limited ductility — 13%, worse than 78% of steel grades
- Limited service temperature — 300°C (572 °F), worse than 78% of steel grades
17B2 properties
Typical room-temperature values for 17B2-+AC+C; bars are the position among steel grades.
Physical3
17B2 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F).
Mechanical14
17B2 has a yield strength of 400 MPa (58 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 60% of steel grades. Elongation at break is 13% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
17B2 is rated for continuous service to 300°C (572 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), better than 75% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
17B2 conducts electricity at 9.5 % IACS, better than 75% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of 17B2 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
17B2's machinability is good (58/100, better than 75% of steel grades); weldability very good (70/100); formability very good (78/100).
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. 17B2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 17B2
Is 17B2 easy to machine?
Soft and somewhat gummy in +AC/+AC+C — use sharp positive-rake tools, high speed and good coolant; machine before hardening or expect ~50 % of soft-state tool life at 29 HRC.
Can 17B2 be welded?
Low carbon equivalent welds readily by MIG/spot/projection, but boron sharply raises HAZ hardenability — keep heat input moderate, avoid welding parts already quenched, and stress-relieve/temper critical joints.
Can 17B2 be formed, bent or molded?
Designed for multi-station cold heading, upsetting and thread rolling in the spheroidize-annealed and drawn condition; use phosphate+lube or polymer carrier and keep drawing reductions per pass modest to preserve heading ductility.
17B2 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 |
|---|---|---|
| Cgrade designator 17 = 0.17 % C nominal | 0.15 – 0.2 | 0.17 |
| Silow Si for cold formability | ≤ 0.3 | 0.15 |
| Mn | 0.5 – 0.9 | 0.7 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Crresidual | ≤ 0.3 | 0.1 |
| Bhardenability agent; requires Ti/Al for free-N control | 8×10⁻⁴ – 0.01 | 0 |
| Tinitrogen fixing so boron stays in solution | ≤ 0.05 | 0.03 |
| Aldeoxidation / N control | 0.02 – 0.06 | 0.04 |
| Fe | balance |
What surface finishes work on 17B2?
No inherent corrosion protection: zinc electroplating (with baking to avoid hydrogen embrittlement above 1000 MPa), hot-dip galvanizing, zinc-flake (Dacromet/Geomet) or phosphate-and-oil are standard; polishes and plates well after pickling.
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 17B2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.5502
How much does 17B2 cost?
17B2 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
17B2 — frequently asked
What is 17B2 used for?
17B2 is typically used for bolts, fasteners and cold-formed parts. In short: higher carbon than 15B2; cold-heading fastener steel; boron-boosted hardenability.
What is the yield strength of 17B2?
17B2 has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is 17B2 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Soft and somewhat gummy in +AC/+AC+C — use sharp positive-rake tools, high speed and good coolant; machine before hardening or expect ~50 % of soft-state tool life at 29 HRC.
Can 17B2 be welded?
Yes — weldability is rated very good (70/100). Low carbon equivalent welds readily by MIG/spot/projection, but boron sharply raises HAZ hardenability — keep heat input moderate, avoid welding parts already quenched, and stress-relieve/temper critical joints.
What surface finishes work on 17B2?
No inherent corrosion protection: zinc electroplating (with baking to avoid hydrogen embrittlement above 1000 MPa), hot-dip galvanizing, zinc-flake (Dacromet/Geomet) or phosphate-and-oil are standard; polishes and plates well after pickling.
Can 17B2 be formed, bent or molded?
Designed for multi-station cold heading, upsetting and thread rolling in the spheroidize-annealed and drawn condition; use phosphate+lube or polymer carrier and keep drawing reductions per pass modest to preserve heading ductility.
What is the maximum service temperature of 17B2?
17B2 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 17B2 cost?
17B2 is a budget-cost steel ($), 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: Steels for quenching and tempering — CEN (2019)
- EN 10083-3 Steels for quenching and tempering — Alloy steels — CEN (2006)
- EN 10027-2 Designation systems for steels — Numeric system (material number 1.5502) — CEN (2015)
- ISO 898-1 Mechanical properties of fasteners — Bolts, screws and studs (property class 8.8) — ISO (2013)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys (boron steels) — ASM International (1990)
- ASM Handbook Vol.14A: Metalworking — Bulk Forming (cold heading) — ASM International (2005)
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.