BS 070M36 Alloy Steel Bar 070M36 Round Bars 070M36 Rods

Product Description

BS 070M36 (En14A) Steel Overview

BS 070M36, formerly known as En14A, is a medium-carbon manganese steel. It is a high-tensile, through-hardening grade that offers significantly better mechanical properties than standard carbon steels like 080M40 (En8). The higher manganese content ($1.30\% - 1.70\%$) is the defining feature of this grade, providing increased strength and improved hardenability, especially in larger diameters.

It is governed by the BS 970 standard and is frequently used where extra toughness and resistance to shock are required in engineering components.

Technical Specifications (Typical)

Chemical Composition (%)

The elevated manganese level allows the steel to achieve a more uniform grain structure and better depth of hardness during heat treatment.

International Equivalents

070M36 is a British Standard designation that corresponds to several global high-manganese carbon steels:

Key Characteristics

1. Hardenability: Unlike standard carbon steels that may only harden on the surface, the manganese in 070M36 ensures that the strength is more consistent throughout the center of the bar.

2. Toughness: It provides excellent resistance to impact and fatigue, making it suitable for parts subjected to high alternating stresses.

3. Machinability: Despite its higher strength, it maintains good machinability in the normalized or annealed state, comparable to other medium-carbon grades.

4. Weldability: Moderate. Due to the manganese and carbon content, it is susceptible to weld-zone cracking. Pre-heating to 150°C–250°C and controlled cooling are recommended for structural welds.

Common Available Formats

• Round Bars: Typically stocked in hot-rolled or bright-drawn conditions. Often supplied in the "T" condition (Quenched and Tempered) for immediate use in high-stress applications.

• Rods: Used for heavy-duty pins, high-tensile studs, and forged mechanical links.

• Forged Blanks: Preferred for complex shapes like steering knuckles and lifting hooks where grain flow is critical for strength.

Common Applications

• Mechanical Engineering: High-load shafts, spindles, gears, and axles.

• Lifting & Rigging: Shackles, high-tensile bolts, and load-bearing pins.

• Automotive: Steering arms, suspension components, and transmission shafts.

• Oil & Gas: Specialized fasteners and structural connectors that require higher yield strength than standard mild steel.

Thermal Processing Data

• Forging: 900°C – 1200°C.

• Normalizing: 840°C – 880°C.

• Annealing: 680°C – 710°C (Slow furnace cool).

• Hardening: 830°C – 860°C (Quench in Oil or Water).

• Tempering: 550°C – 660°C to achieve the specific mechanical property "condition" (e.g., Condition R, S, or T).