A versatile treatment for surface hardening.

Carburizing is a thermochemical diffusion process where carbon (via natural gas) is absorbed into alloy and carbon steels to a specified depth to achieve a very high hardness or “case” on the surface of a part. The part is first heated to above the austenitizing temperature (1500 – 1750°F) in a carbon enriched atmosphere, then subsequently oil quenched to transform the microstructure of the steel to achieve the high hardness at and below the surface of the part, while the core of the part remains softer.

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  • High hardness achieved on part surface while using less expensive alloy steels.
  • Unlike carbonitriding, case depths can be created up to and above 0.100″.
  • Core hardness remains softer, tougher, ductile, and impact resistant.
  • Increases wear resistance, fatigue, and tensile strengths.
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  • High temperature processing can cause some distortion.
  • Generally, a grinding operation is required after treatment to restore dimensional tolerances.
  • Parts can discolor or scale from oil quench and subsequent tempering operation.

Equipment Used

  • Atmosphere batch integral quench furnace.
  • Working dimensions 36″ W x 48″ L x 36″ H.
  • Weight capacity approximately 2,500 lbs.

Materials (Alloys) Treated

Plain carbon and alloy steels (8620, 4320, 1020, etc.).


Gears, engine components, tools, fasteners, and many others.


Automotive, aerospace, mining, power generation, construction, firearms and more.


  • AMS2759/7 (DMT’s furnace is not yet qualified for this spec).
  • OEMs and Tier 1 suppliers generally create their own specifications for carburizing.

Contact DMT to Learn What We Can Do For You

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Need Machining as well?

Our sister company, TMD Machining, is a precision machine shop, so much so, that they specialize in aerospace solenoid valves. If you’re looking for a high quality machine shop, check out TMD.