MT Heat Treating Incorporated

MT Heat Treat Inc. is a family owned business located 30 miles east of downtown Cleveland in Mentor Ohio. O. V. Mathews is the president of MT Heat Treat business for 47 years.

O.V. takes great pride in the fact of knowing he has a wonderful and hard working staff. Please feel free at any time to stop and take a tour of our 65000 square foot facility. Do not hesitate to call with any question you may have.

“Treat others the way that you’d like to be treated. I love keeping a clean and updated facility and I am proud to say I do it not only for my employees but also for my customers.”  O.V. Mathews   President / M T Heat Treat Inc


Available Services include:

Harden & Draw / Quench & Temper

The thermal process operation used to increase the hardness & strength of steel. Performed by heating material to the proper austenitizing temperature & holding for sufficient time to achieve partial of complete transformation to martensite, then quench in sutable medium. Tempering is performed by reheating the material to a temperature below the transformation range then cooling under suitable temperature. Tempering improved ductility & toughness and reduces the quecnhed hardness to desired hardness.


Painting of a No Carb. Paint to prevent Carburizing on an area of the material.

Deep Freeze (Cryrogenic)

Exposing to suitable subzero temperatures for the purpose of obtaining desired conditions or properties such as dimensional or micro-structural stability. When the treatment involves the transformation of retained austenite, it is usually followed by tempering.

Stress Relieving

A process to reduce internal residual stresses in a metal object by heating the object to a suitable temperature and holding for a proper time at that temperature. Followed by cooling slowly enough to minimize the development of new residual stresses. This process may be applied to relieve stressed induced by casting, quenching, normalizing, machining, cold working, or welding.

100 % Inspection

The hardness testing of all part in a job that has be heat treated.


Documentation providing the heat treating processed performed on a job along with the final hardness if required. Certification will also show the customer’s specifications and upon request show the time and temperature of the heat treating process.

Furnace Charts

Charts that have information populated by the furnace as load are being heat treated.


Heat treating of Brass material as per customer specification.

Age Hardening / Aging / Precipitation Hardening

A time-temperature-dependent change in the properties of certain alloys. For each alloy susceptible to aging, there is a unique range of time-temperature combinations to which it will respond. The result of precipitation form a solid solution of one or more compound whose solubility decreased with decreasing temperature.


A thermal treatment consisting of heating to a suitable temperature above the transformation range and then cooling in still air. Usually employed to improve toughness or machinability, or as a preparation for further heat treatment


A thermal cycle involving heating to, and holding at a suitable temperature and then cooling at a suitable rate, for such purposed as reducing hardness, improving machinability, facilitating cold working, producing a desired microstructure, or obtaining desired mechanical or other properties.

Air hardening & Oil/Water Tool Steel

A Harden & Draw / Quench & Temper that involves the heat treating of various type of tool steel.


A process that consists of absorption and diffusion of carbon into a solid ferrous alloy by heating to a temperature above the upper transformation temperature of the specific alloy. Heating is done in a carbonaceous environment. This produces a carbon gradient extending inward from the surface, enabling the surface layer to be hardened to a high degree by quenching from a temperature 200 degree F below the carburizing temperature.