4S106 Nitriding Steel Bar 4S106 Alloy Steel Round Bars

Product Description

Technical Summary

• Standard: BS 4S106 (Aerospace specification, replacing 3S106)

• Supply Condition: 4S106D — Hardened, Tempered, Stress Relieved, and Bright Finished (Peeled/Ground)

• Type: 3% Chromium-Molybdenum (Cr-Mo) Nitriding Steel

• Tensile Strength: 930 – 1080 MPa (Core)

• Surface Hardness (Post-Nitriding): 650 – 800+ HV1 (~58 – 64 HRC)

• Commercial Equivalent: BS 970 722M24 / EN40B | DIN 1.7361 / 1.8522

Common Processing Steps

1. Rough Machine: Leave ~0.5 – 1.0 mm finishing allowance.

2. Stress Relief: Heat to 550°C – 580°C (30°C above nitriding temperature).

3. Finish Machine / Grind: Machine to final pre-nitride tolerances.

4. Nitride: Gas or plasma nitriding at 500°C – 530°C for desired case depth (0.20 – 0.60 mm).

5. Technical Summary

   • Standard: BS 4S106 (Aerospace specification, replacing 3S106)

   • Supply Condition: 4S106D — Hardened, Tempered, Stress Relieved, and Bright Finished (Peeled/Ground)

   • Type: 3% Chromium-Molybdenum (Cr-Mo) Nitriding Steel

   • Tensile Strength: 930 – 1080 MPa (Core)

   • Surface Hardness (Post-Nitriding): 650 – 800+ HV1 (~58 – 64 HRC)

   • Commercial Equivalent: BS 970 722M24 / EN40B | DIN 1.7361 / 1.8522

   Common Processing Steps

   1. Rough Machine: Leave ~0.5 – 1.0 mm finishing allowance.

   2. Stress Relief: Heat to 550°C – 580°C (30°C above nitriding temperature).

   3. Finish Machine / Grind: Machine to final pre-nitride tolerances.

   4. Nitride: Gas or plasma nitriding at 500°C – 530°C for desired case depth (0.20 – 0.60 mm).

   5.