Guide to Choosing Carbon and Alloy Steel Bar Stock

Choosing the appropriate steel for industrial applications requires careful consideration of mechanical properties, machinability, and cost-effectiveness. This guide examines key carbon and alloy steel grades to help engineers and manufacturers optimize material selection.

This low-carbon steel offers excellent case-hardening properties and is well-suited for bending and cold forming. While not classified as free-machining steel, it provides good brazing and welding characteristics.

Applications: Carburized parts where core strength is secondary; commonly used for shafts.

Available Forms: Round, square, flat, hexagonal

Technical Specifications:

• Chemical Composition: C: 0.15-0.20, Mn: 0.60-0.90, P: ≤0.04, S: ≤0.05
• Mechanical Properties: Tensile: 64,000 psi, Yield: 54,000 psi, Elongation: 15%

A medium-carbon steel suitable for heat treatment (quenching and tempering), though it responds moderately to conventional quenching. Widely used in induction hardening applications.

Applications: Medium-strength components requiring wear resistance; hydraulic/pneumatic cylinder shafts.

Technical Specifications:

• Chemical Composition: C: 0.43-0.50, Mn: 0.60-0.90
• Mechanical Properties: Tensile: 91,000 psi, Yield: 77,000 psi

This grade has largely replaced similar free-machining steels like 1212, offering faster machining speeds and superior surface finish. Not recommended for welding or carburizing.

Applications: Automatic screw machine parts not subject to severe stress.

A leaded, re-sulfurized free-machining steel ideal for high-volume production. Excellent for parts requiring extensive machining while maintaining good ductility.

Applications: Bushings, inserts, couplings, and fittings produced on automatic screw machines.

This chromium-molybdenum alloy steel responds well to heat treatment, offering excellent hardness penetration, wear resistance, and toughness.

Applications: High-stress components subject to severe wear.

The most widely used carburizing alloy steel, combining nickel's toughness with chromium/molybdenum's wear resistance. Produces parts with hard surfaces and tough cores.

Applications: Gears, pinions, splined shafts, and other critical components.

Manufactured using a patented elevated-temperature drawing process, this high-strength material eliminates need for heat treatment and secondary operations.

Key Features: Suitable for induction hardening; electromagnetic testing via eddy current.

This stress-relieved steel provides consistent machining performance without heat treatment, featuring minimum 100,000 psi yield strength and guaranteed machinability.

Quality Assurance: Each batch undergoes proprietary machining-based performance testing to ensure uniformity.

The selection of appropriate steel grades requires balancing mechanical requirements with production efficiency. Understanding these material properties enables optimal performance in final applications while controlling manufacturing costs.