Carbon Steel 1020 Round Bar

Carbon Steel 1020 Round Bar is a solid cylindrical bar rolled or drawn from low-carbon, non-resulphurised plain carbon steel 1020 (UNS G10200). The chemical composition is governed by ASTM A29/A29M and SAE J403. Hot-wrought special-quality bar is supplied to ASTM A576 and cold-finished bar to ASTM A108.

The grade carries 0.18-0.23% carbon with 0.30-0.60% manganese. This low carbon level gives high ductility, cold-forms without cracking and welds by all the common processes, usually with no preheat in normal bar sections. It will not through-harden by quenching. For a hard wearing surface the part is carburised, carbonitrided or induction case-hardened, which leaves a hard skin over a core that stays tough.

Bars are supplied hot rolled, hot rolled and annealed, normalised, or cold drawn. Cold drawing raises tensile and yield strength through work hardening, improves surface quality and tightens diameter tolerance. Hot-rolled bar remains more economical for large sections and for parts that will be heavily machined or hot formed. Peeled, turned, centreless-ground and polished finishes are offered where closer tolerance or a decarburisation-free surface is needed.

Diameters run from roughly 3 mm in cold-finished sizes up to 350 mm and larger in hot-rolled and forged sizes. Random lengths of 3-6 m are standard and cut-to-length supply is widely available.

Typical uses include shafts, pins, spacers, studs, cold-headed bolts and fasteners, machined components, welded assemblies, structural supports, and carburised gears, camshafts and bushings. Industries served include automotive, agricultural and construction machinery, general engineering, fabrication, material handling and oilfield support equipment. It is one of the cheapest engineering bar grades and is stocked almost everywhere, which is why so many high-volume turned and cold-headed parts start life as this bar.