1045 Precision Ground Shaft (ASTM A108)

A 1045 Precision Ground Shaft is a high-quality, medium-carbon steel round bar known for its combination of moderate strength, good machinability, and superior dimensional accuracy.

The common industry term for this product is 1045 TGP (Turned, Ground, & Polished).

Composition

1045 is a carbon steel (the "10" series) with approximately 0.45 carbon content. This medium-carbon content gives it greater strength and hardness than lower-carbon steels like 1018.

Properties

It offers a good balance of strength and toughness suitable for general-purpose mechanical components. It responds well to heat treatment (like induction hardening) to achieve a hard, wear-resistant surface if required.

The finish is the key feature, ensuring high precision and straightness.

• Process: The bars are typically turned, ground, and polished.
• Dimensional Accuracy: This process delivers very tight diameter tolerances and exceptional straightness. Tolerances are always on the minus side.
• Surface Finish: The polishing results in an extremely smooth surface (low RMS value), which is crucial for reducing friction and wear when the shaft is used with bushings, or seals.

1045 Precision Ground Shafting is the most common choice for general industrial shafting because it balances performance, machinability, and cost.

• Rotating Components: Motor shafts, hydraulic piston rods, pump shafts, and conveyor rolls.
• Machinery Parts: Axles, spindles, gears, bolts, and studs.
• High-Speed Needs: The high degree of straightness is particularly important for high-speed applications to prevent vibration and ensure a long life for mating parts.