Garner Heat Treat has extensive experience heat treating in Northern California with over 175 years of collective heat treating experience. We specialize in fast turnaround, excellent quality control, customized work to suit customer applications and pick up and delivery in most areas.
Deep Cryogenic Processing Provides 80% to 500% more wear resistance from your machine and sheet metal shop cutting tools, tooling, dies, molds and most heat treated industrial parts. Stabilizes metals and plastics as well.
Bright Annealing Annealing in a protective atmosphere to prevent discoloration of the surface. The purpose is to prevent scaling.
Vacuum (Bright) Hardening Heating under vacuum, typically prior to quench hardening. Quench hardening is normally a two step process, for steel it involves heating to austenitizing temperature, holding for temperature uniformity and cooling at a rate fast enough to develop high hardness (quenching). Vacuum (sub-atmospheric pressure) is used to remove air that would discolor the heated parts. Some surface oxides may also be reduced resulting in a surface improvement.
Note that as-quenched hardness of steel is normally brittle-hard and must be tempered to increase toughness/ductility for practical use.
Cryogenic Treatment
Cooling to a low (cryogenic) temperature, usually -100 to -320 F, to stabilize microstructure and dimensions; typically for high alloy (tool) steel parts. The treatment is carried out after quenching, or more appropriately after the first temper, to transform Retained Austenite to Martensite which is then tempered. Error! Hyperlink reference not valid.
Garner Heat Treat, Inc. utilizes the latest in Computerized Vacuum Technology. This assures precision in heat processing by providing distortional and dimensional stability.
The 5-Bar Vacuum Furnace offers unparalleled control in heating and quenching operations. The 5-Bar's ability to perform interrupted quenching minimizes the potential for distortion and cracking. Skilled operators using advanced tools and methods, evaluate each part and setup loads to minimize distortion and optimize dimensional stability.
Deep Cryogenic Process Garner Heat Treat, Inc. offers deep cryogenic processing of products to -320oF. Cryogenic processing increases dimensional stability, wear resistance, and the performance of most alloys through conversion of retained austenite to martensite and through precipitation of finer carbides.
GHT's -320oF deep cryogenic process improves performance and increases the life of most products provided to customers.
GHT's deep cryogenic process is completely computer controlled. Products are slowly cooled to -320oF at a predetermined rate based on the material size, type, and hardness. After soaking for the specified time interval, the products are slowly ramped-up to room temperature then tempered at the appropiate tempering temperature.
Garner Heat Treat, Inc., offers deep cryogenic processing of products to -320oF. Cryogenic processing increases dimensional stability, wear resistance, and the performance of most alloys through conversion of retained austenite to martensite.
Wear Improvement of Shallow Cryogenic (-120) vs Deep Cryogenic (-320) Cycle
-320oF deep cryogenic processing allows GHT to offer customers improved performance and increased life of metal tools and parts. Other deep-freeze methods reach only -120oF. Our innovative cryoprocessing takes metals beyond deep freeze to cryogenic levels transforming almost all soft retained austenite to hard martensite. This creates a significantly denser molecular structure resulting in a larger contact surface area that reduces friction, heat, and wear. The computer controlled ramps virtually eliminate thermal shock.
Benefits of Deep Cryogenic Processing
Conversion of most retained austenite to martensite. Stabilizes alloys without changing shape or size of product. Cryogenically treating welds returns the metal to its original state. Increased durability and wear life.
What Does Deep Cryogenic Treating do? These ultra-cold temperatures, below -310oF, will greatly increase the strength and wear life of all types of vehicle components, castings and cutting tools. In addition, other benefits include reduced maintenance, repairs and replacement of tools and components, reduced vibrations, rapid and more uniform heat dissipation, and improved conductivity. Cryogenics process is like an insurance policy for your tools and components.
Comparative microphotographs (1000x) of steel samples show the change in micro structure produced by the controlled deep cryogenic process. Uniform, more completely transformed micro structure and less retained austenite at right, is related to improvements in strength, stability, and resistance to wear.
Primary Atmosphere Heat Treating Services
Carburizing & Hardening
Carbonitriding & Hardening
Selective Carburizing & Hardening
Neutral Hardening / Oil Quench
Precipitation Hardening
Air Tempering / Stress Relieving
Nitrogen Tempering
Ferritic Nitrocarburizing
Aging
Aluminum Stress Relieving
OTHER SERVICES
Aging A change in a metal or alloy by which its structure recovers from an unstable or metastable condition produced by quenching (quench aging) or by cold working.
The degree of stable equilibrium obtained for any given grade of steel is a function of time and temperature. Aging which takes place slowly at room temperature may be accelerated by a slight increase in temperature.
Annealing Heat treat process consisting of heating to and holding at a temperature above the transformation temperature followed by slow cooling in the furnace at a suitable rate primarily for the purpose to soften metallic materials.
Processes include full process, normalizing, tempering, martempering are some principal ways by which steel is softened.
Austenite A solid solution of one or more elements in face-centered cubic iron. Unless otherwise designated (such as nickel austenite), the solute is generally assume to be carbon. This is the initial step prior to normalizing, full annealing and quench hardening of ferrous alloys.
Austenitic Steel An alloy steel whose structure is normally austenitic at room temperature.
Brazing Heat treat process that joins solid materials together by heating them to a suitable temperature using a filler metal with a liquidus temperature below the solidus temperature of the base materials.
Brinell Hardness A hardness number determined by applying a known load to the surface of the material to be tested through a hardened steel ball of known diameter. The diameter of the resulting permanent impression is measured. This method is not suitable for measuring the hardness of sheet and strip.
Carbonitriding A thermochemical treatment involving the incorporation of both carbon and nitrogen into the surface of the component simultaneously. This process is carried out at a lower temperature than carburizing and therefore components are less prone to distortion.
The use of nitrogen as well as carbon allows carbonitriding to be used on lower alloy
steels. The purpose is to produce a thin, hard, wear resistant surface. This process is
generally performed on low hardenability steel.
Carburizing A case hardening process for the absorption and diffusion of Carbon into the surface of ferrous ( low-carbon steel) alloys to provide a surface layer of high hardness. The Carbon is added by heating the workpiece to an
austenitizing temperature in contact with carbon-rich particles packed around them (pack carburizing), or in a carbon-rich gas (gas carburizing).
The surface is hardened either by quenching directly from the carburizing step, or sometimes slow cooled to room temperature then reheated to austenitizing temperature and quenched. In a similar process, Carbonitriding, Nitrogen and Carbon are added to the surface for extra-high
hardness and/or lower temperature processing.
Case Hardening A process of surface hardening involving a change in the outer layer of steel alloy by inward diffusion from a gas or liquid followed by appropriate thermal treatment.
Typical hardening processes are carburizing, carbo-nitriding and nitriding.
Cold Treatment 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.
Hardening Heat treat process which increases hardness by heating and cooling. The formation of martensite in alloy when quenched rapidly from a temperature above the transformation temperature. Hardening of steels is done to increase the strength and wear properties. One of the pre-requisites for hardening is sufficient carbon and alloy content. If there is sufficient carbon content then the steel can be directly hardened.
Heat Treatment Is the controlled heating and cooling of metals to alter their physical and mechanical properties without changing the product shape.
Heat treatment is often associated with increasing the strength of material, but it can also be used to alter certain manufacturability objectives such as improve machining, improve formability, restore ductility after a cold working operation. Thus it is a very enabling manufacturing process that can not only help other manufacturing process, but can also improve product performance by increasing strength or other desirable characteristics.
Martensite Is a microconstituent or structure in quenched steel characterized by an acicular or needle -like pattern on the surface of polish. It has the maximum hardness of any of the structures resulting from the decomposition products of austenite.
Neutral Hardening Heating for hardening under a protective atmosphere (or vacuum) that is essentially non-reactive to the surface of the workpiece, which normally means that the surface of the steel parts are neither carburized or
decarburized.
Normalizing The process of heating steel just above the critical temperature and air cooling to a temperature below the transformation range. It can help eliminate growth in parts during subsequent hardening, thus minimizing finish grinding. It is especially recommended for 8620 or 9310 parts that are to be carburized, such as gears. Usually a low cost normalizing step prior to machining will result in a part that can be made closer to size, saving time, aggravation and money.
Purpose - Used as a conditioning, notably for refining the grains of steel that have been
subjected for forging or other hot work applications. It is usually followed by another
heat treating process ( quench and temper, etc.).
Quenching Hardening alloys by heating above the transformation temperature and then cooling at a rate to transform the austenite to martensite. Typical quench mediums include air, oil, water, salt and polymers.
Rockwell Hardness Test An indentation hardness test based on the depth of penetration of a specified penetrator into the specimen under certain arbitrarily fixed conditions.
Stress Relieve Heat treat process consisting of heating steel below the transformation temperature to relieve internal stresses (from processes such as forming, machining or welding) followed by slow cooling.
Tempering Heat treat process consisting of reheating a quenched steel at a temperature below the transformation range to decrease hardness and increase toughness.
