300M Alloy Steel

300M

Description

300M is a low alloy, vacuum melted, steel of very high strength. Essentially it is a modified AISI 4340 steel with silicon, vanadium and slightly greater carbon and molybdenum content than 4340. 300M has a very good combination of strength (1900-2100 MPA after final heat treatment), toughness, fatigue strength and good ductility. 300M is a through hardening alloy. 

Specific Gravity

 7.83 g/cm3

Typical Applications

Related Specifications

Aircraft Landing Gear

Driveshafts

High Strength bolts

Gears

AMS 6257

AMS 6417

AMS 6419

BS S155

BMS 7-26

MTL 1201

MIL S 8844 

Chemical Composition (Wt %)

  C Si Mn P S S+P Cr Mo Ni V
Min  0.39 1.5 0.6 - - - 0.7 0.3 1.65 0.05
Max 0.44 1.8 0.9 0.015 0.015 0.025 0.95 0.45 2 0.10

Typical Mechanical Properties

  0.2% Proof Stress Tensile Strength Elongation Reduction of area
  MPA MPA % %
  Min Min Max Min Min
Longitudinal 1550 1900 2100 8 30
Transverse 1550 1900 2100 5  20

Hardness after Heat Treatment

534 - 601 HB

52 - 55 HRC 

* Every effort has been made to ensure that our technical specifications are accurate. However, technical specifications included within Dynamic Metals Ltd should be used as a guideline only and are subject to change without notice.