--- title: Services description: Learn more about National Thermal's services including Heat Treating, Neutral Hardening, Blasting, and Hardness Testing. image: https://nationalthermalprocessing.com/hubfs/v1%20(2).jpg --- [Skip to content](https://nationalthermalprocessing.com/neutral-hardening#main-content) [![National Thermal Logo](https://nationalthermalprocessing.com/hs-fs/hubfs/Logo-1.png?width=153&height=150&name=Logo-1.png)](https://www.nationalthermalprocessing.com?hsLang=en) - [Home](https://nationalthermalprocessing.com/) - [Services](https://nationalthermalprocessing.com/services) Show submenu for Services - [Heat Treating](https://nationalthermalprocessing.com/heat-treating) - [Annealing](https://nationalthermalprocessing.com/annealing) - [Neutral Hardening](https://nationalthermalprocessing.com/neutral-hardening) - [Blasting](https://nationalthermalprocessing.com/blasting) - [Hardness Testing](https://nationalthermalprocessing.com/hardness-testing) - [About](https://nationalthermalprocessing.com/about) - [Contact](https://nationalthermalprocessing.com/contact) Open main navigation Close main navigation - [Home](https://nationalthermalprocessing.com/) - [Services](https://nationalthermalprocessing.com/services) Show submenu for Services - [Heat Treating](https://nationalthermalprocessing.com/heat-treating) - [Annealing](https://nationalthermalprocessing.com/annealing) - [Neutral Hardening](https://nationalthermalprocessing.com/neutral-hardening) - [Blasting](https://nationalthermalprocessing.com/blasting) - [Hardness Testing](https://nationalthermalprocessing.com/hardness-testing) - [About](https://nationalthermalprocessing.com/about) - [Contact](https://nationalthermalprocessing.com/contact) - [Print Our Certificates](https://nationalthermalprocessing.com/certificates) [Print Our Certificates](https://nationalthermalprocessing.com/certificates?hsLang=en) # Neutral Hardening ## What is Neutral Hardening? Neutral Hardening is a heat-treating process that utilizes neutral salt to maintain carbon levels within alloy steels.  Neutral salt protects the alloy from Carburization or decarburization. Alloy steels are then quenched into either Quench oil or Quench salt. Neutral salt baths are kept at an approximate range of 1,350-1,750 degrees Fahrenheit.  The process of neutral hardening greatly increases the strength of the alloy being quenched. - ##### Alloy Steel - ##### Copper Alloys - ##### Stainless Steel - ##### Aluminum - ##### Nickel Alloys ![neutralhardening](https://nationalthermalprocessing.com/hs-fs/hubfs/neutralhardening.jpg?width=2687&height=2432&name=neutralhardening.jpg "neutralhardening") --- ![v1 (2)](https://nationalthermalprocessing.com/hs-fs/hubfs/v1%20(2).jpg?width=2498&height=2434&name=v1%20(2).jpg "v1 (2)") --- ## What items require Neutral Hardening Manufacturers for all industries, including Aerospace, Automotive Racing, Molding, etc. use heat treating processes to modify metals and alloys. Every time you see a piece of metal or plastic, it has most likely been through a heat treating process that has included neutral hardening, from the smallest screws to rocket ship tips and earth mover chassis.  Manufactured pieces of metal or plastic have strength and performance requirements that can be met by heat treating and neutral hardening procedures. ## 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 ![neutralhardening](https://nationalthermalprocessing.com/hs-fs/hubfs/neutralhardening.jpg?width=2687&height=2432&name=neutralhardening.jpg "neutralhardening") --- ## 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. ![metal1](https://nationalthermalprocessing.com/hs-fs/hubfs/metal1.jpg?width=1920&height=1598&name=metal1.jpg "metal1") --- ## Request a Quote from Our Team ## 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 ![metal2](https://nationalthermalprocessing.com/hs-fs/hubfs/metal2.jpg?width=1920&height=1796&name=metal2.jpg "metal2") --- [facebook-f icon](https://www.facebook.com/Nationalthermal/) [linkedin-in icon](https://www.linkedin.com/company/national-thermal-processing/about/) --- [![National Thermal Processing Logo](https://nationalthermalprocessing.com/hubfs/Logo-1.jfif "National Thermal Processing Logo")](http://www.Nationalthermalprocessing.com) 14651 Mallory Drive, Fontana, CA 92335 Copyright © 2023, National Thermal Processing [Privacy Policy](https://nationalthermalprocessing.com/privacy-policy?hsLang=en)