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Hardness Testing

What is Hardness Testing

Hardness testing is a process by a heat treat facility to verify that materials meet customer or applicable specifications flowed down by the manufacturer. Hardness machines, such as Rockwell machines, use a diamond tip penetrator to penetrate the surface of the material and convert the hardness readings to the scale that is being used for testing. There are many different hardness scales that are used for different types of materials. These scales can be changed due to the strength or configuration of the materials being tested.



What items require Hardness Testing?

Manufacturers for all industries, including Aerospace, Automotive Racing, Molding, etc. use heat treating processes to modify metals and alloys and then require hardness testing to verify the new hardness levels. Every time you see a piece of metal or plastic, it has most likely been through a heat treating process and hardness testing, from the smallest screws to rocket ship tips and earth mover chassis

Neutral Hardening

A process using oil & salt quenching to harden steel without any oxidation or scaling.  This process also hardens without adding or taking away carbon from the steel.

  • Alloy Steel

Our Quality Policy

National Thermal Processing shall deliver the services and products that meet the customer's requirements. National Thermal Processing commits to continuous improvements by training its people, upgrading equipment, eliminating nonessential practices, and creating a quality conscious environment.


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Hardness Testing

After each order is treated, our team performs a hardness inspection to verify the metal meets the customer's specifications.

  • Alloy Steel

  • Copper Alloys

  • Stainless Steel

  • Aluminum

  • Nickel Alloys

  • Composites