Need steel for aerospace bearings, power transmissions, and other flight-critical components that can resist corrosion and maintain high performance even under harsh temperatures? We stock specialty steel in a variety of high-quality grades to meet the strict demands of aerospace and defense manufacturing.

Our Featured Aerospace Steels


A double-vac melted steel that maintains hardness characteristics at high temperatures.


A double-vac melted steel that combines  high hot hardness and corrosion resistance.


An M50 variant suited for applications that require both surface strength and fatigue resistance.

Learn more about M50

Learn more about BG-42

Learn more about M50NiL

See our full list of aerospace steels

Steel in Aerospace and Aviation

Aerospace-grade steel is highly specialized to perform in demanding environments. These steels must be alloyed and heat treated to balance desired weight parameters with the necessary strength, durability, corrosion-resistant, and temperature-resistant characteristics to assure safe, reliable function in aircraft and spacecraft.

As a result, there are strict regulatory standards that these materials must meet during quality control testing. Because standards are so strict, finding qualified mills and suppliers for aerospace-grade steels can be a challenge, especially when supply lines are tight. Major engine manufacturers qualify steel mills that meet their quality criteria — Sullivan Steel, for example, is an authorized distributor under Pratt & Whitney’s LCS certification.

Applications for Aerospace Steel Alloys

Flight-critical components must be made with steels that won’t fail under extreme conditions. Engines typically require steel made to withstand high temperatures, with high fatigue and high hot hardness, while wing flaps and actuation systems need to be manufactured with steel resistant to outside elements. For non-flight critical components like hinges, manufacturers may be able to choose from a greater variety of air-melted steels.

Aerospace Steel at Sullivan

Aerospace has been at the center of Sullivan Steel’s mission since our start in 1980 with aircraft-quality bearing materials. Since then, we’ve worked with major aircraft parts manufacturers to supply steel for many critical applications in the aerospace and defense markets, including:

  • Bearings
  • Ball Screws
  • Helicopter Shafts
  • Landing Gear Components
  • Hydraulic Parts
  • Gas Turbine Parts
  • Military Weaponry

Our Aerospace Grades

All of the steel grades we carry are suited for use in at least some aerospace applications. If needed, we can offer both air-melted and double-melted grades.

Sullivan Grade

Typical Aerospace Application

M50 VAR and VIM-VAR Aircraft engine bearings, helicopter rotor bearings, gas turbines; high stress, high temperature environments
BG-42 Critical bearings and gas turbines; high temperature, high corrosion environments
M50NiL Aircraft bearings and gears; high temperature, high stress environments
XD15NW Bearings and ball and roller screws in highly corrosive environments; high corrosion, high stress environments
XD16N Gears, valves, injection systems; high stress, high temperature, high corrosion environments
52100 VAR and VIM-VAR Aircraft bearings
440C Bearings, ball screws; high stress, moderately corrosive environments
4340 Aerospace gears, shafts, and other components; high stress environments
CX13VDW Stainless carburizing grade for aerospace ballscrew and rod end applications
GKHW Deep nitriding grade for critical mechanical components
GKPYW Deep nitriding grade for shafts and heavy loaded gears
Nitriding 135M Gears; high stress environments
9310 Gears and heavy-duty gear shafts
8620 Carburizing bearing and gear steel for aerospace and industrial applications
NC310YW High strength carburizing grade for shafts and gears

Have questions about finding the proper steel for your particular aerospace application? Our steel experts can help — drop us a message using our Live Chat feature or visit our contact page.