Application
Shafts & Axles
Torque carrying and fatigue loaded components, where through-section strength and straightness matter.
The requirement
What this application actually demands
A shaft is loaded in torsion and bending, usually reversing, usually for a long service life. That combination makes fatigue the governing failure mode — and fatigue is driven as much by surface condition and steel cleanliness as by nominal tensile strength.
Medium carbon steel is the natural choice because it through-hardens. Unlike a carburised part with a hard skin over a soft core, a hardened and tempered shaft has useful strength across the whole cross section, which is what a torque path needs.
Straightness is the requirement that quietly causes the most trouble. A bowed bar means runout, runout means vibration and uneven bearing load, and on a long shaft the machining stock allowance has to be increased to clean up — wasting material and time. Our straightening operation is a controlled process step, not an afterthought.
Where a shaft is turning-intensive rather than load-critical, EN8M delivers the same mechanical class with substantially better machinability.
Grade selection
Recommended grades, and why
EN8
First choiceEN8 Bright Bar
Machinability 60 · Weld Fair
The standard shafting grade. 600–750 MPa as drawn, and hardenable past 850 MPa when the application needs it.
EN8D
EN8D Bright Bar
Machinability 60 · Weld Fair
For fatigue loaded and heat treated shafts. Tighter chemistry and lower P and S give cleaner steel, more consistent hardness and better fatigue life.
EN8M
EN8M Free Cutting Bright Bar
Machinability 80 · Weld Limited
For high-volume turned shafts where cycle time drives cost. Roughly a third faster to machine than EN8 at the same strength class.
20MnCr5
20MnCr5 Case Hardening Alloy Bright Bar
Machinability 52 · Weld Limited
For carburised splined and transmission shafts needing a hard wearing surface over a high strength core.
Heat number carried through to your gate
Other applications
Also making something else?
Fasteners
High-volume turned and cold formed fasteners, where cycle time decides the cost per piece.
Gears & Transmission
Carburised gears and pinions, where case depth consistency and traceability decide whether the batch is accepted.
Auto Components
Tier-1 and Tier-2 automotive parts, where documentation is part of the product.
Hydraulic & Pneumatic
Sealing surfaces and pressure-carrying parts, where surface finish and tolerance are the specification.
General Engineering
The broad base of engineering work — machined parts, fabricated assemblies and everything in between.
Supplying into shafts & axles?
Send us the grade, size and quantity — or tell us the component and we will recommend the grade.