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Customer Service


Shipping/Receiving Hours

7:00am - 4:00pm

Customer Service


Shipping/Receiving Hours

7:00am - 4:00pm


Interested in learning more about General Metal’s high-quality heat treating services? We pride ourselves in our ability to consistently meet the needs of our customers with accuracy and effectiveness, while providing clear and safe working conditions. If you need heat treating services done efficiently and with custom tailored processes, trust your work to General Metal Heat Treating.

Heat Treating Services

Also called Precipitation Hardening, this process increases the hardness of the material by heating it at a relatively low temperature for hours in order to allow the precipitation to take place.

Though metals such as aluminum, copper, lead, steel, and zinc tend to transform over time due to exposure to natural environmental elements, aging is a heat treatment that can accelerate this process while under the careful watch of an expert heat treating team. During aging, or precipitation hardening, there needs to be care taken to ensure that the materials do not revert to their original configuration and that the process doesn’t continue past a specific time.

  • Enhanced strength of alloys
  • Helps certain metals achieve high coercivity
  • Helps eliminate unstable conditions of a metal, brought upon by prior operation

Annealing heat treatment allows the material to be softer and easier to machine, removing any internal stresses that may have been created during the forming process. It is typically used to increase the ductility of all types of steel, as well as other non-ferrous metals such as copper and aluminum.

Annealing is a heat treatment process of heating metals to a specified temperature for a set period of time, then cooling the metal to room temperature. The method of cooling will largely depend on the properties desired. In order for the annealing process to be successful the cooling period has to happen slowly, and with great care.

Types of annealing we offer:

  • Full annealing
  • Process annealing
  • Stress relief annealing
  • Spherodize annealing
  • Isothermal annealing

Austemper is a hardening treatment, which consists of quenching in a molten salt bath maintained at an elevated temperature and holding. The benefits include improved ductility and a reduction in distortion.


Carbonitriding is a metal heat treating process that combines carburizing and nitriding. It is typically used to increase the surface hardness of small metal components by producing a wear-resistant case, and is best used when shallow case depths are required. If you’re looking for a cost-effective heat treatment method for mass produced parts or inexpensive steel, carbonitriding heat treatment is a great solution!

Types of carbonitriding applications include:

  • pistons
  • gears
  • rollers and bearings
  • shafts
  • levers

       … and more!


Carburizing heat treatment involves adding carbon atoms to the outer surface of the steel. Carburizing — also called case hardening — changes the chemistry of the workpieces at their surface, while leaving the interior chemistry unchanged.

The surfaces produced by carburizing are tougher, and resistant to damage and wear. However, this process allows all treated metals to maintain their strength at the core. Bearings, gears and other low carbon steel components are usually treated with carburizing.

Though carburizing has been a heat treating process for a long time, companies like General Metal Heat Treating have evolved the methods using advanced heat treating techniques and equipment. These improvements mean our carburizing process yields improved hardness and durability. Have a complex shape that needs heat treating? No problem!


Marquenching is a type of quenching in which the steel is quenched rapidly until the hardening temperature is uniform, then cooled in air to room temperature. The advantages include reduction in distortion and a reduced risk for cracking.


This process involves heating the material to above the critical temperature range, holding this temperature, and then slow cooling at room temperature. This allows the material to be softer and easier to machine, and removes any internal stresses that may have been created during the forming process. Another benefit to normalizing is that it can leave the material stronger and harder than if it underwent a full annealing process.

Stress Relieving

This process involves heating the steel and holding this temperature long enough to reduce any internal stresses. The material is then slowly cooled to prevent the development of any new stresses.


This process is also referred to as drawing and is applied after hardening the steel. The material is reheated to a relatively low temperature and then slowly cooled in order to relieve stresses and increase ductility.

Additional Services

We are able to offer blasting services in-house including sand blast and vacuum blast.

Deep Freeze (Cryogenic)

The deep freeze is another process that can improve hardness and wear and achieve the proper microstructure. Through the use of a liquid nitrogen system, sub-zero temperatures as low as -120°F are accurately controlled to completely transform austenite into martensite.

Metallurgical Testing

We are able to provide Brinell Hardness, Rockwell Hardness, Case Depth, and Micro Structure testing and evaluation in our in-house lab and inspection facilities.

Salt Baths

Our salt baths allow us to handle precision machined tool steel parts which are finished to size before heat treating but required hardening to as high as 65Rc with minimum distortion and change. Because salt baths heat by conduction rather than radiation, heat is applied more evenly and quickly.

Vacuum Heat Treating

Vacuum processing protects the steel from oxidation and provides low distortion.

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