Gas Nitriding Heat Treatment for Machined Parts, Stampings, and Tooling by ThermTech

ThermTech is a pioneering figure in providing gas nitriding heat treatment for machined parts, stampings, and tooling. Gas nitriding, a heat treatment technique, introduces nitrogen into the surface layer of steel components using an ammonia gas atmosphere at elevated temperatures. It has emerged as an essential process, particularly for case-hardened machined components with wear surfaces.

Technical Benefits of Gas Nitriding:

  • Superior Wear Resistance: The formation of iron nitrides enhances the wear resistance, prolonging the component’s lifespan.
  • Optimized Fatigue Life: Essential for parts like gears under cyclical loads, the nitrided layer boosts fatigue strength.
  • Minimal Distortion: With its operation at relatively lower temperatures compared to other techniques, gas nitriding minimizes thermal stresses and distortions, making it perfect for parts where tight tolerances are paramount.
  • Improved Corrosion Resistance: The process enhances the corrosion resistance of certain steel grades.
  • Controlled Case Depth: The nitriding time and temperature offer precise control over the desired case depth.

Gas Nitriding Capabilities by ThermTech:

ThermTech’s specialized gas nitriding treatments include:

  • Gas Nitriding 4140 (pre-hardened)
  • Gas Nitriding S-7 (pre-hardened)
  • Gas Nitriding H-13 (pre-hardened)
  • Gas Nitriding P-20
  • Gas Nitriding Nitralloy 135M

Moreover, selective gas nitriding is achievable through nitride stop-off paints, allowing for targeted treatment areas.

Batch-Type Retort Furnaces:

ThermTech’s state-of-the-art approach utilizes batch-type retort furnaces, ensuring:

  • Optimum process and lot control.
  • AMS 2750 compliant furnaces.
  • Capabilities include working dimensions of 33.5” DIA X 53” long or 30” DIA x 78” long.

Case Depth:

ThermTech is adaptable to client needs:

  • Shallow case depth load (0.003”) runs every weeknight with a rapid 24-hour turnaround.
  • Nitriding heat treatment for deeper case depths is a standard offering.
  • However, they do not provide gas nitriding services for stainless steel.

Gas Nitriding Process at ThermTech:

  • Previously hardened parts are heated in a controlled environment to a temperature below their prior tempering temperature.
  • The temperature is maintained proportionate to the case depth requirement.
  • Post nitride hardening, parts are hand-blasted using aluminum-oxide blast media to eliminate excess nitride stop-off paint.
  • Growth due to gas nitriding process ranges from .0005-.001” due to the deposition of the white layer.

Gas nitriding, with its myriad of benefits, ensures machined parts, stampings, and tooling are equipped for durability, strength, and enhanced performance. With ThermTech’s expertise, you’re guaranteed a precise and efficient heat treatment process. For inquiries on deeper case depths and other specifics, reach out to ThermTech’s dedicated Customer Support.

ThermTech—Experts in Austempering Stampings, Machined Parts, and Investment Castings

ThermTech, Inc. offers both small and large batch capabilities for austempering steel and iron investment castings. Between our neutral salt bath furnaces and our larger austempering furnaces, we have the capabilities to austemper a wide variety of stamping, machined components, and investment castings. We have run austempering on alloys from 1060 through 4340 to ductile iron machined parts.

Our dedicated team works with you to ensure we meet your specifications. Count on our decades of experience with hardening, tempering, surface heat treatments, vacuum treatments, and annealing. To learn more about our services, please contact us today.

Learn more about austempering and how ThermTech can serve you by watching these videos.

Request a free quote online or call us at 800-752-6917. You can also contact us online for all your austempering and heat treating needs.

Error: Contact form not found.


ThermTech’s quality policy is ZERO DEFECTS for all customer products and in all quality management system activities. Through our efforts to continually improve the quality of the work we offer, we’ve been recognized as being able to meet the rigorous quality standards required by several of our major customers. ThermTech is certified for ISO 9001 and AS9100 in both Metal Heat Treat and Metal Finishing.