Product Name

Medium Carbon Steel (Medium Steel)

Introduction

Medium Carbon Steel (often called medium steel) occupies the middle range of carbon content between low-carbon (mild) and high-carbon steels. With balanced strength, toughness and ductility, it is widely used where higher mechanical properties are required than mild steel but full alloy or heat-treatable steels are not necessary. Typical uses include shafts, axles, gears, couplings, crankshafts, heavy structural components and general engineering parts.

Typical Chemical Composition (approximate ranges)

Carbon (C): 0.30 – 0.60 wt% (most common grades ~0.40–0.50%)

Manganese (Mn): 0.50 – 1.20 wt%

Silicon (Si): 0.10 – 0.40 wt%

Phosphorus (P): ≤ 0.035 wt% (max per spec)

Sulfur (S): ≤ 0.040 wt% (max per spec)

Other elements: small additions of Cr, Mo or V available in some medium-carbon alloy variants

Common commercial examples: AISI/SAE 1040, 1045, 1050; EN equivalents such as C45, C50.

Typical Mechanical Properties (depends on grade & heat-treatment)

As-rolled/normalized (typical):

Yield strength: ~250 – 420 MPa

Tensile strength: ~430 – 700 MPa

Elongation: 10 – 20 %

Quenched & tempered: significantly higher strength (yield up to 700+ MPa) with controlled toughness

Hardness (HRC/HB): as-rolled ~120–220 HB; heat treated higher depending on temper

(Values are indicative - furnish exact grade and heat treatment to receive precise data.)

Forms & Supply Conditions

Product forms: Bars (round, square, flat), billet, plate, forgings, seamless/cold-drawn tube, strip.

Lengths: standard mill lengths or cut-to-length; blanks and forgings per drawing.

Surface finish: hot-rolled mill, normalized, pickled/oiled, cold-drawn (for precision sizes), ground or polished.

Common standards: ASTM A29/A108, EN 10083 (for heat-treatable steels), JIS equivalents.

Heat Treatment & Fabrication

Weldability: Moderate - preheat and controlled interpass temperatures recommended for higher-carbon end of range; low hydrogen electrodes and post-weld heat treatment (PWHT) sometimes required.

Forming: Cold forming limited as carbon rises; better when annealed/normalized.

Machinability: Good for 0.30–0.45%C grades; improved with free-machining variants.

Typical heat treatments: Normalizing (refine grain), quench & temper (raise strength and toughness), annealing (soften for machining), case hardening (for wear surfaces while retaining a ductile core).

Key Features & Advantages

Balanced properties: Higher strength and wear resistance than mild steel while keeping reasonable ductility and toughness.

Heat-treatable: Responds well to normalizing and quench-and-tempering to tailor mechanical properties.

Cost-effective: Economical choice when higher strength is needed without expensive alloy steels.

Versatile forms: Available as bar, tube, plate and forgings for many engineering applications.

Typical Applications

Shafts, axles, spindles, pins and couplings

Gears, sprockets and bearing housings (often surface-hardened)

Crankshafts, connecting rods and machine tool parts

Forged components: yokes, levers, heavy brackets

Automotive, agricultural machinery, construction equipment and general engineering parts

Quality Assurance & Testing

Mill Test Certificate (MTC): Chemical and mechanical test reports supplied per order.

Mechanical tests: Tensile, yield, elongation; hardness testing as required.

NDT: Ultrasonic, magnetic particle, PMI or RT/UT on critical components or per customer spec.

Microstructural checks: Grain size, inclusion rating or heat-treatment validation on demand.

Packaging & Delivery

Bundled and strapped with timber/polymer spacers for bars and tubes.

End protection and rust-preventive oil for long term storage or export.

Custom packaging for precision ground or polished products.

Typical lead times: stock items 3–10 days; custom heat-treated or forged parts 2–8 weeks depending on scope.

Ordering Information / What We Need

Please specify: desired grade (e.g., AISI 1045 / EN C45), product form (bar/plate/tube/forging), dimensions & tolerances, required heat treatment (as-delivered condition), quantity, and any testing or certification needs (MTC, NDT, PMI). If the part is load-bearing, include expected service loads and environment to ensure correct grade and treatment selection.

If you want, I can:

provide a side-by-side comparison of medium vs low vs high carbon steel,

generate a recommended grade & heat-treatment for a specific shaft/gear application, or

produce a material datasheet (chemical/mechanical table) for a selected grade. Tell me which and I'll prepare it.