BS 527M17 Alloy Steel Bar 527M17 Round Bars 527M17 Rods

Product Description

BS 527M17 (historically referenced under BS 970) is a low-alloy, manganese-chromium case-hardening (carburizing) steel. It is formulated to achieve a high surface hardness after carburizing, while maintaining a durable, impact-resistant core.

Round bars and rods made of 527M17 are heavily relied on in general engineering, precision machining, and heavy manufacturing for parts subjected to high friction, shock, and localized stress.

Technical Specifications & Cross-References

In global material sourcing, BS 527M17 overlaps deeply with the standard manganese-chromium chemistry family. The most common equivalent international designations include:

Chemical Composition

The material utilizes a lean addition of chromium and a robust concentration of manganese to achieve predictable depth of hardening (hardenability) during heat treatment.

• Carbon (C): 0.14% 0.19% (low base carbon ensures core remains tough and non-brittle after quenching)

• Manganese (Mn): 1.00% 1.30%

• Chromium (Cr): 0.80% 1.10%

• Silicon (Si): max. 0.40%

• Phosphorus (P): max. 0.025%

• Sulfur (S): max. 0.035%

Key Mechanical Properties & Supply Conditions

• Supply State: Typically stocked and delivered in the As-Rolled, Normalized, or Soft Annealed condition (usually max. 207 HBW) to minimize tool wear during initial machining, turning, or gear cutting.

• Core Strength Post-Heat Treatment: Once carburized, quenched, and tempered, it develops a high core tensile strength (typically 7001000 MPa depending on the ruling section size) and excellent fatigue strength.

• Ruling Section Limitations: It has low-to-medium core hardenability, making it ideal for small-to-medium component cross-sections (typically up to 40 mm50 mm thickness) where consistent core properties are required.

Core Applications

Because 527M17 provides a highly wear-resistant "case" with a fracture-resistant core, its round bars and rods are heavily favored for:

• Power Transmission: Medium-stressed gears, pinions, splined shafts, and gearboxes.

• Fasteners & Hardware: High-strength structural pins, heavy-duty bolts, gudgeon pins, and specialized bushings.

• Mechanical Components: Camshafts, joints, and universal linkages exposed to abrasive sliding wear.