Steel 32CrB4
EN 32CrB4
32CrB4 (1.7076) is a low-alloy chromium steel micro-alloyed with boron, giving hardenability comparable to higher-alloy grades at lower cost, and belongs to the EN 10083 alloy-steel family.
Reference datasheet — 32CrB4 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
32CrB4 tempers and conditions
32CrB4 is supplied in 8 conditions, soft to hard. +AC+C is the default FabDigit quotes; the values on this page are for it.
Compare all 8 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Pick when maximum cold-heading/upsetting formability is needed and the drawer will size the material in-house. | 370 | 570 | 20 | 167 HB | — |
Annealed | General soft delivery condition for bar to be machined or hot-formed before hardening; cheaper than spheroidizing but less headable. | 390 | 600 | 18 | 180 HB | — |
Supplied with specified (narrow) hardenability band, untreated/as-rolled | Order this when the fastener or part maker must guarantee end-quench (Jominy) hardness after their own quench and temper; delivery is as-rolled with a Jominy band, not hardened bar stock. | 450 | 700 | 15 | 18 HRC | — |
+AC+CDefault Spheroidized (soft) annealed and cold drawn | Standard cold-heading wire/bar condition: spheroidal carbides plus a light draw for size, tolerance and straightness before header/bolt-forming. | 540 | 640 | 12 | 190 HB | — |
Cold drawn | Cold-drawn bar/wire for machined parts and light upsetting where tight tolerance and straightness matter more than maximum headability. | 660 | 760 | 8 | 21 HRC | — |
Quenched and tempered to ~900 MPa | High-tempering condition (≈560–620 °C) for shafts, pins and class 8.8 fasteners where toughness and delayed-fracture safety outrank peak strength. | 750 | 900 | 14 | 28 HRC | — |
+QT | The volume condition for 32CrB4: oil/polymer quench from ~860 °C, temper ≈425–500 °C, for ISO 898-1 property class 10.9 bolts and screws. | 990 | 1,100 | 11 | 35 HRC | — |
+QT | Highest strength condition (temper ≈380–420 °C) for class 12.9 socket screws; use only with strict hydrogen and notch control because delayed-fracture risk rises sharply. | 1,150 | 1,280 | 9 | 41 HRC | — |
What is 32CrB4?
32CrB4 (1.7076) is a low-alloy chromium steel micro-alloyed with boron, giving hardenability comparable to higher-alloy grades at lower cost, and belongs to the EN 10083 alloy-steel family. It is chosen mainly for cold-headed high-strength fasteners and small shafts, supplied as wire, rod and bar in +A, +AC, +AC+C or +C condition and then quenched and tempered to property class 10.9 or 12.9. In the default condition it gives 540 MPa yield, 640 MPa tensile, 12 % elongation and about 190 HB, with service limited to roughly 400 °C. Weldability is poor and there is no inherent corrosion resistance, so a coating is required; the nearest non-boron alternatives are 34Cr4 and 41Cr4. 32CrB4 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). 32CrB4 has a yield strength of 540 MPa (78.3 ksi) and a tensile strength of 640 MPa (92.8 ksi) — stronger than 70% of steel grades. Elongation at break is 12% and the elastic modulus is 210 GPa (30.5 Msi).
What is 32CrB4 used for?
- high-strength bolts
- fasteners
- small shafts
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- Forms and bends easily — 70/100, better than 86% of steel grades
Limitations
- Limited ductility — 12%, worse than 84% of steel grades
32CrB4 properties
Typical room-temperature values for 32CrB4-+AC+C; bars are the position among steel grades.
Physical3
32CrB4 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).
Mechanical15
32CrB4 has a yield strength of 540 MPa (78.3 ksi) and a tensile strength of 640 MPa (92.8 ksi) — stronger than 70% of steel grades. Elongation at break is 12% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
32CrB4 is rated for continuous service to 400°C (752 °F). It conducts heat at 44 W/m·K (25.4 BTU/hr·ft·°F), better than 57% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
32CrB4 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 32CrB4 takes about 26 MJ of energy and emits 1.9 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.
Manufacturability7
32CrB4's machinability is good (60/100, better than 83% of steel grades); weldability fair (35/100); formability very good (70/100).
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. 32CrB4 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 32CrB4
Is 32CrB4 easy to machine?
Machine in +AC/+A/+C condition (≈60 % of AISI 1212) with carbide inserts; after Q&T above 32 HRC expect reduced tool life and prefer grinding or hard turning for finish features.
Can 32CrB4 be welded?
Poor weldability — CE ≈ 0.55–0.65: preheat 200–300 °C, low-hydrogen consumables and post-weld temper are mandatory, and any weld destroys the fastener's Q&T properties, so it is normally not welded.
Can 32CrB4 be formed, bent or molded?
Cold heading/upsetting and thread rolling are done in the +AC or +AC+C condition; keep drawing reductions moderate and phosphate/lubricate wire, then quench from 850–870 °C and temper to the required class.
32CrB4 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 10263-4 / EN 10083-3 range | 0.3 – 0.34 | 0.32 |
| Si | ≤ 0.3 | 0.2 |
| Mn | 0.6 – 0.9 | 0.75 |
| P | ≤ 0.03 | 0.02 |
| Smax; lower for cold-heading quality | ≤ 0.03 | 0.01 |
| Cr | 0.9 – 1.2 | 1.05 |
| Bhardenability booster; needs Ti/Al to fix free N | 8×10⁻⁴ – 0.01 | 0 |
| Tiusual practice to protect the boron effect (not always specified) | ≤ 0.05 | 0.03 |
| Fe | balance |
What surface finishes work on 32CrB4?
No natural corrosion resistance: zinc or Zn-Ni electroplate, zinc-flake (Dacromet/Geomet), phosphate + oil, or hot-dip coat; for parts ≥1000 MPa bake within 4 h of plating to relieve hydrogen and avoid delayed fracture.
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 32CrB4 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.7076
How much does 32CrB4 cost?
32CrB4 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
32CrB4 — frequently asked
What is 32CrB4 used for?
32CrB4 is typically used for high-strength bolts, fasteners and small shafts. In short: boron hardenability at low cost; cold-heading fastener steel; poor weldability.
What is the yield strength of 32CrB4?
32CrB4 has a typical yield strength of 540 MPa (78.3 ksi) and a tensile strength of 640 MPa (92.8 ksi) — stronger than 70% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is 32CrB4 easy to machine?
Reasonably — machinability is rated good (60/100, better than 83% of steel grades). Machine in +AC/+A/+C condition (≈60 % of AISI 1212) with carbide inserts; after Q&T above 32 HRC expect reduced tool life and prefer grinding or hard turning for finish features.
Can 32CrB4 be welded?
With care — weldability is rated fair (35/100). Poor weldability — CE ≈ 0.55–0.65: preheat 200–300 °C, low-hydrogen consumables and post-weld temper are mandatory, and any weld destroys the fastener's Q&T properties, so it is normally not welded.
What surface finishes work on 32CrB4?
No natural corrosion resistance: zinc or Zn-Ni electroplate, zinc-flake (Dacromet/Geomet), phosphate + oil, or hot-dip coat; for parts ≥1000 MPa bake within 4 h of plating to relieve hydrogen and avoid delayed fracture.
Can 32CrB4 be formed, bent or molded?
Cold heading/upsetting and thread rolling are done in the +AC or +AC+C condition; keep drawing reductions moderate and phosphate/lubricate wire, then quench from 850–870 °C and temper to the required class.
What is the maximum service temperature of 32CrB4?
32CrB4 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 32CrB4 cost?
32CrB4 is a budget-cost steel ($), 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: steels for quenching and tempering — CEN (2017)
- EN 10083-3 — Steels for quenching and tempering: alloy steels — CEN (2006)
- ISO 898-1 — Mechanical properties of fasteners: bolts, screws and studs — ISO (2013)
- GB/T 6478 / GB/T 3077 — SAC (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.4A — Steel Heat Treating Fundamentals (boron hardenability) — ASM International (2013)
- Cold-heading quality boron-chromium wire datasheets (32CrB4 / 1.7076) — European & Chinese special-steel wire producers (2023)
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.