4140 CF Annealed
Chemical Composition
Carbon:               0.38%-0.43%
Manganese:          0.75%-1.00%
Chromium:            0.80%-1.10%
Silicon:                 0.15%-0.30%
Molybdenum:         0.15%-0.25%
4140 is typically bought to meet chemistry requirements rather than physical requirements. For that reason, physical properties are generally not provided unless requested prior to production. Any material can be sent to a third party after production to be tested for physical properties.
Typical Uses
Typical uses for 4140 include:
  • Jigs
  • Fixtures
  • Drill Collars
  • bolts
  • Stubs
  • Couplings
  • Axles
  • Shafting
  • Piston rods
  • Rams
  • Gears

4140 CF Annealed

Alro stocks 4140 CFA -a steel in the family of SAE steel grades, as specified by the Society of Automotive Engineers (SAE). Alloying elements include chromium and molybdenum, and as a result these materials are often informally referred to as chromoly steel (common variant stylings include chrome-moly, CrMo, CRMO, CR-MOLY, and similar). They have an excellent strength to weight ratio and are considerably stronger and harder than standard 1020 steel, but are not easily welded (need pre and post weld thermal treatment to avoid cold cracking). While these grades of steel do contain chromium, it is not in great enough quantities to provide the corrosion resistance found in stainless steel.