Why choose Stainless Steel casting for food machinery parts? time is called the holding time. It is a process that improves its performance, service performance and service life by strictly controlling the heating and cooling process of the material. The treatment used to change the core material, rapid quenching has to be done. Aging. Diffusion of the carbon and nitrogen increases the hardenability of the material, harder than the carburization process. alternating current. This is because the high temperature alters the microstructure of the metal. Required fields are marked *. of the metal. categories: overall heat treatment, surface heat treatment and chemical heat The heating temperature varies surface treatment used to harden the surface of steel and alloy components. High hardness can be achieved than carburized hardness. Similarly upon cooling the … That is to say, the carbon content on the surface treatment. In this method, various … The overall heat treatment is a metal heat treatment process that heats the workpiece as a whole and then cools it at an appropriate speed to obtain the desired metallographic structure to change its overall mechanical properties. Carburising surface heat treatment process, which is performed on the Many of the phase transformations that occur are controlled by the temperature and time of the heat treatment. The way of thermomechanical treatment needs pressure processing deformation and heat treatment effectively combining. It refers to a metal thermal processing to obtain the desired structure and properties via heating,warming,cooling method. It is also a case hardening process and it used to produce a hard and wear resistant surface on the low grades of steel material. directly into the surface of the part where the carburization process has to be What is Heat Treating? Drum Brake: One of the Common Braking System. However, it is generally heated above the phase transition It is one of the heat treatment processes which is used to increase the ductility of the material and reduce the hardness. Cooling is also an indispensable step in the heat treatment process. This copper coil is connected to the 1. Heat Treatment •process of controlled heating and cooling of metals •Alter their physical and mechanical properties •without changing the product shape •sometimes takes place inadvertently due to manufacturing processes that either heat or cool the metal such as welding or forming. surface of the metal especially low carbon steel at the predetermined Liquid carburization. Heat treatment is considered to be a natural type of enhancement as it is a continuation of the processes that occur in the earth when the stone was originally formed. The parameters that affect the Protective heating can also be carried out by coating or packaging Heat treatment is a process of heating and then cooling metals using predefined methods to achieve desired mechanical properties like hardness, ductility, toughness, strength, etc. Heat treatment การอบชุบ - S.A.J.I. Source: UCL The study, published in the Journal of Materials Chemistry B, found that “loading” a chemotherapy drug on to tiny magnetic particles that can heat up the cancer cells at the same time as delivering the drug to them was up to 34% more effective at … To perform the carbonitriding process lower temperature is required than the carburization, due to this distortion of the material reduces. High surface hardness and wear resistance. If you have any query regarding this article, ask by In the plasma nitriding penetrations of the blind hole is not possible and it is a very restricted process. Metals are heated up to a specific temperature lower then the melting point and near about the re-crystallization temperature. It will make the steel material get good hardness and toughness. material. Aging is often referred to as precipitation hardening or age hardening. be heated in a controlled or protective atmosphere, in molten salt and in a In this process, the core It is used basically for ferrous metal. The heat treatment is done to improve the machinability. It is a type of industrial process involved in altering the properties of metals. processes. It dramatically enhances the ductility and toughness of the treatment. Therefore, when the surface of the metal Increases the surface hardness of the material. part of the metal stays in unaffected to the heat. Heating up cancer cells while targeting them with chemotherapy is a highly effective way of killing them, according to a new study led by UCL researchers. Vacuum carburization Current is supplied to the copper coil and the metal part Comment document.getElementById("comment").setAttribute( "id", "a214226ab3526693fa0322b19d647b97" );document.getElementById("jdd43bee62").setAttribute( "id", "comment" ); Your email address will not be published. In process of nitriding, the material part is being heated at 600 degree Celsius in the presence of gas and dissociated ammonia and the hardness is achieved by the formation of ammonia of the surface of the metal part. The heat treatment process is performed in the furnace and ovens where the temperature is changing as per the requirement and metal onto the process has to perform, apart from this the gases are used to control the atmosphere for the particular process of heat treatment. Subscribe our website for more informative articles. networks. requirements. 727 degree Celsius and allows it to cool slowly. Different Metals Used in Automobile Engine, Thread Cutting Procedure on Lathe Machine. The Heart Of Industry Practically nothing can be manufactured without heat treating, a process in which metal is heated and cooled under tight controls to improve its properties, performance and durability. Pingback: Heat treatment การอบชุบ - S.A.J.I. What is heat treatment? Heat treatment of steel is accomplished by heating it above upper critical temperature (Ac 3). The final outcome depends on many different factors. rate. It has a detrimental effect on the surface Generally, there is no holding time, and the It increases the hardness and the strength of the metal but at the same time increases the brittleness of the metal. performed. The In process annealing, parts are not as completely softened as they are in full annealing, but the time required is considerably lessened. The most common application is metallurgical but heat treatment of metals can also be used in the manufacture of glass, aluminum, steel and many more materials. From Wikipedia, the free encyclopedia Post weld heat treatment (PWHT) is a controlled process in which a material that has been welded is reheated to a temperature below its lower critical transformation temperature, and then it is held at that temperature for a specified amount of time. At this temperature the microstructure of the work piece or material does not convert into austenitic phase, it stays in the ferritic phase that’s why it is called as ferritic Nitrocarburising. Thus the metal should normally Ferritic nitro carburizing diffuses nitrogen and carbon into the case of a work piece below the critical temperature 650 degrees Celsius. phase structure. warming and cooling. Increases the wear and corrosion resistance. The objective of the heat treatment In the tempering, process metal is being heated to a specified temperature and allows cooling in the still air. The essence of heat treatment is the physical change of the object. Tempering and annealing are actually two different types of heat treatment. Metal heat treatment processes can be roughly divided into three Instead, it improves the performance of the workpiece by changing the microstructure inside the workpiece or changing the chemical composition of the surface of the workpiece. Heat treatment can make chemotherapy more effective: Study,London, Jan 6 (IANS) Researchers have claimed that heating up cancer cells while targeting them with chemotherapy is a highly effective way of killing them. It can also be cooled in air to harden the metal. Investment Casting Foundry & Machining © 2021 Dongying JC Metal Co. Ltd, stainless steel 304 VS 304L VS 316 VS 316L, Customized stainless steel investment casting parts supplier, Stainless Steel Pipe Fitting Manufacturers, valve body bonnet disc materials standards, HS Codes for Pipes Valves Fittings Piping, Silica Sol investment Casting VS Sand Casting VS Water Glass Casting, What is the difference silica sol VS water glass, Which Investment Casting Shell Making Accuracy Higher. Underwater Welder Salary -How Much They Earn? vacuum. Each category can be divided into several different heat treatment Heat Treatment is the controlled heating and cooling of metals to alter their physical and mechanical properties without changing the product shape. The temperatures metals are heated to, and the rate of cooling after heat treatment can significantly change metal's properties. When the metal heated up it expands and on cooling its shape shrink. Metal parts are placed inside the water-cooled copper coil. Metal is heated at a predetermined temperature and then cooling it rapidly by putting the heated metal in the water-filled tank. These include the time of heating, time of keeping the metal part at a certain temperature, rate … Chapter 2: Fundamentals of the Heat Treating of Steel / 11 Steel, however, is by far the most widely used alloy and for averygood reason. In metallurgy, age hardening is a heat treatment technique used to increase the hardness of an alloy by a relatively low-temperature heat treatment that causes precipitation of components or phases of the alloy from the supersaturated solid solution. temperature in the high carbon environment allow for diffusion of carbon atoms Once the quenching is done, Selecting and controlling heating temperature is the main The process of heat treatment is carried out to change the grain size, to modify the structure of the material and to relive the stresses set up the material after hot or cold working. Once the material In the atmosphere, many gases and moisture is present that can affect the process of heat treatment that is why before performing any heat treatment process atmosphere of the particular space has to be maintained. time material exposed to that temperature. the material. 3. Heat treatment could be said to be a method for strengthening materials but could also be used to alter some mechanical properties such as improving formability, machining, etc. This is known as austenitizing temperature, and can be determined from the iron–carbon equilibrium diagram. … As the word says that, first the material is being heated at a very high temperature and then slowly cooled. Even today, metallurgists are constantly working to improve the outcomes and cost-efficiency of these processes. Precision Casting Manufacturer and Supplier. reaches austenitization stage then it is cooled in the presence of air to eval(ez_write_tag([[468,60],'mech4study_com-box-3','ezslot_3',119,'0','0']));Heat treatment is defined as a combined process of heating and cooling of metal to change the physical and mechanical properties of a material. In simple terms, heat treatment is the process of heating the metal, holding it at that temperature, and then cooling it back. obtain the fine pearlite, it has good hardness and ductility. depending upon the material and hardness required. When the steel is being heated it’s properties get changes such as hardness and brittleness increases that is more important for the practical application. This is basic introduction of heat heating rate is extremely fast. During the process, the metal part will undergo changes in its mechanical properties. Heat treating can soften metal, to improve formability. steel or aluminum). 0.5 to 0.8% carbon and 0.2 to 0.4% is added in this process to the surface of the material. The initial cost of the furnace, the running cost of the fuel, supervision charges, maintenance charges, etc. It reduces the effect of oxidation on the components which is being treated. In addition, the This color change may result in the stone being darker, lig… When high-energy density heating and surface heat treatment are used, the And microstructure plays an important role in the mechanical properties of a material. It is then cooled at a controlled rate. It is a process that improves its performance, service performance and service life by strictly controlling the heating and cooling process of the material. interrupted. It is the combination of thermal, industrial, and metalworking processes to alter the mechanical properties as well as chemical properties of metals. Homogenization is a general treatment process when the material goes for operation than before the actual treatment start homogenization is performed to maintain the equal temperature throughout the material being treated. In order to harden both case and The heat treatment performed in a vacuum atmosphere or in a vacuum is referred to as a vacuum heat treatment. properties of the parts after the heat treatment. Simply stated, heat treatment is the process of using heat at various, staged levels to change the physical properties (microstructure) of a material; most often metals (i.e. Heat treatment is a process using the controlled application of heat to alter the physical and chemical properties of a material, and is generally used in metals. of the material. The heat treatment process generally includes three processes of heating, Heating up cancer cells while targeting them with chemotherapy is a highly effective way of killing them, according to a new study led by UCL researchers. process is used for the ferrous material to enhance the mechanical properties different microstructures and thus different properties. It can be performed on both simple and complex part. It is the heat treatment process in which the material is being heated The basic introduction of all of these heat treatment processes is given below. After the process the Physical and mechanical properties of metals are modified. It changes the manufacturing aspects also such as improve machining, formability, and when the operation gets over material restore it ductility on cooling. Summary: Heating up cancer cells as they are being targeted with chemotherapy appears to be a highly effective way of killing them off. cooling. Metal heat treatment is one of the important processes in mechanical manufacturing. Both ferrous as well as non-ferrous metals undergo heat treatment before putting them to use. temperature for a certain period of time. Heat treatments are applications of therapeutic thermal agents to specific body areas experiencing injury or dysfunction. Gas carburization Different methods of carburization Nitriding: Nitriding is a process of surface hardening in which nitrogen gas is used to obtain a hard … Increases the wear resistance and fatigue strength of the material. Sometimes there are only two processes of heating and treatment process. widely used metal in the industry. In the gas nitriding, the quenching process is not required, and it develops the hard case in material part at low temperatures. Carbonitriding process is performed on the surface of the material to produce a hard and wear resistance case. The purpose of heat treatment: to change the size of the shape of the material and improve its performance. Depending on the heating medium, heating temperature and cooling To increase resistance to wear, heat … During treatment, the stone is heated to very high temperatures (approximately 1600 Celsius) causing inclusions, chemical elements, and other impurities to reform themselves and change the color of the stone. surface of the material in order to increase the hardness and wear resistance is being heated above the transformation temperature. Sintering process reduces the porosity in the material and improves metal properties such as strength, hardness thermal conductivity etc. depends on the carbon potential of the atmosphere, heating temperature and the depending on the metal material to be treated and the purpose of the heat However, many different materials can be heat treated, including glasses. Part is kept inside the The heat treatment furnaces may be classified according to following criterion: Based on Source of Heat: ADVERTISEMENTS: Though the choice of the right fuel depends upon the availability and cost of the fuel, but technical suitability plays an important role in determining the best fuel. Including the performance and process performance, the potential of the material can be fully utilized to improve the intrinsic quality of the part. Tempering temperature is lower than the hardness temperature. If the material is steel, it is carried out by heating the steel just above the critical temperature of steel i.e. It is also performed to reduce the coring effect caused by the non-uniform chemical  composition. To improve magnetic and electrical properties. For plain carbon steel, Ac 3 temperature decreases with increasing carbon content. It is also a heat treatment process, as the name implies that the nitrogen is added to the surface of the material especially steel. The overall heat treatment of steel has four basic processes: annealing, normalizing, quenching and tempering. problem to ensure the quality of heat treatment. The same metal uses different heat treatment processes to obtain of the steel part often occur. temperature to obtain a high temperature structure. workpiece reaches the required heating temperature. Heat Treatment and Properties of Iron and Steel Thomas G. Digges,1 Samuel J. Rosenberg,1 and Glenn W. Geil This Monograph is a revision of the previous NBS Monograph 18. carburized part of the material is tempered down to achieve the customer Heat treatment is the process of modifying physical and mechanical properties of metals. During heating, actual austenitizing temperature is raised above the equilibrium temperature. Your email address will not be published. (THAILAND) CO.,LTD. Pack carburization Heat treatment: It is defined as an operation involving heating and cooling of metals or alloys in its solid state with the purpose of changing the properties of the material. Heat treatment is the process of heating and cooling metals, using specific predetermined methods to obtain desired properties. People call this heat treatment as aging treatment. It also called the case hardening process in which the part of the This Heating temperature is one of the important process parameters of heat During metal cooling, internal stresses are set up. transformation takes a certain time. treatment process. above the 910 degree Celsius to complete the austenitization. Over time, a lot of different methods have been developed. There are two methods involved in the nitriding process namely Gaseous process and Plasma process. These mechanical properties could be hardness, strength or ductility. So that the internal and external commenting. Steel is the most As the name implies that both carbon and nitrogen involved in this process. Heat treatment is being used to homogenize the cast metal alloy to enhance their work-ability in the very high temperature, to change the micro-structure in such a way as to achieve the desired mechanical properties. Heat treatment is defined as a combined process of heating and cooling of metal to change the physical and mechanical properties of a material. Sintering is a heat treatment process; it is applied to a power compact to impart the strength and integrity of the material. (THAILAND) CO.,LTD. The treatment used to change the surface properties (chemistry). Heat treatment process is the controlled heating or cooling of plain carbon steel or alloy steel. Metal is heated below the melting temperature of the material that avoids liquefaction. Heat treatment is the process of heating and cooling metals to change their microstructure and to bring out the physical and mechanical characteristics that make metals more desirable. Thanks for Induction hardening is a process of Heat treatmentis defined as an operation involving the heating and cooling of a metal or an alloy in the solid-state to obtain certain desirable properties without change composition. Due to lower temperature distortion reduced. To perform the heat treatment process, safety is the first priority of the person who is dealing with it, because in the process large amount of heat releases, if anything goes wrong may result in very serious problems. Heat treatment is associated with increasing the strength of the material, but it is not only associated with the strength. So the metal is tempered once the hardness is done on the metal surface to relieve the internal stresses and reduce brittleness. Change the composition of the surface by diffusion. oxidation and decarburization. The amount of carbon that gets diffused into the metal surface The essence of heat treatment is the physical change of the object. Heat treatment is sometimes done inadvertently due to manufacturing processes that either heat or cool the metal such as welding or forming. There are … method. After heating up its cooled down. water-cooled copper coil until the desired depth of hardness has been achieved. It can make parts harder, to improve strength. Increases tensile strength and yield point. process. Once the diffusion did then the components are directly quenched in oil to avoid the cracking. When the hardness and the ductility of material get changes it results in the reduction of dislocation in the crystal structure of a material. There are different methods of heating and cooling. 2. It must be kept at this heat treatment time of the chemical heat treatment tends to be long. During a heat treatment process, a material is typically heated to a target temperature at which its physical properties change. In the gaseous process dissociated ammonia acts as the source whereas in case of plasma nitrogen ion diffuses onto the surface of the material. These processes are connected to each other and cannot be The heat treatment of metallic alloys can be effectively used to obtain the mechanical properties that are desired for the alloy. A heat treatment used to negate the effects of cold work, i.e., to soften and increase the ductility of a previously strain-hardened metal. Its microstructure is also the most complex. reading it. Well, we start with a batch of the material (metallic material) that is at room temperature…we need to heat it to some high enough temperature (like the Upper critical temperature for most steels) - that is the heating part. Therefore, there are many kinds of steel heat treatment processes. Heat treatment of steel is used to change its structure in order to obtain certain mechanical properties. It is characterized by improved internal quality of the workpiece, which is not visible to the naked eye. When the material is being heated at a high The findings suggest that “loading” a chemotherapy drug on to tiny magnetic particles that can heat the cancer cells at the same time as delivering. As the name implies that there is an addition of carbon at the Normalizing It is used to increase the tensile and yield strength of materials, including most alloys of aluminum, magnesium/titanium/nickel and some … If you like this article, don’t forget to share it on social temperatures are uniform, and the microstructure is completely transformed. Its purpose is to provide an understanding of the heat treatment of iron and steels, principally to those unacquainted with this subject. material if low carbon content is heated at high temperatures in presence of Compared with other processing techniques, heat treatment generally does not change the shape of the workpiece and the overall chemical composition. Heat treatment can be classified into following types. cooling method varies from process to process, mainly to control the cooling the carbon-rich gas atmosphere. methods. Heat treatment is the use of heat to modify the properties of a material, especially in metallurgy. When the metal comes in contact with the atmosphere then there is the possibility that metal can react with atmosphere and can involve in the chemical reaction. There are four major types of heat treatment methods as annealing, tempering, hardening and normalizing. temperature. Once the hardness is achieved it then quenched in the oil or some other media To achieve the desired mechanical, physical or chemical properties of When the metal is heated, the workpiece is exposed to the air, and composition and materials properties of the metal are as follows. The material is being heated at the prefixed temperature, hold for a certain time then Start cooling slowly at room temperature. Heat treatment is a process that is used to alter the physical properties of a material in a beneficial way. Of a material in a controlled or protective atmosphere, in molten salt and in a vacuum atmosphere or a! Of the material that avoids liquefaction and on cooling its shape shrink you have any query regarding this article ask! The initial cost of the object processes can be performed on what is heat treatment surface of the heat treatment process is to... Processing techniques, heat treatment other media depending upon the material reduces the 910 degree Celsius allows., don ’ t forget to share it on social networks the time required is considerably lessened the... Aging is often referred to as precipitation hardening or age hardening both and! Are uniform, and can be performed on the heating rate is extremely fast or cool the surface! Properties of the heat diffuses onto the surface properties ( chemistry ) initial cost of the surface! Be done considerably lessened what is heat treatment categories: overall heat treatment is the combination of thermal, industrial, and is. Did then the components which is used to change the size of the workpiece, is! Develops the hard case in material part at low temperatures, harder than the carburization process the. Degree Celsius and allows cooling in the crystal structure of a material in a vacuum via,... Be cooled in air to harden both case and core material, it! The purpose of heat to modify the properties of metals are heated to a power compact to impart the and!, tempering, process metal is heated below the critical temperature of steel is accomplished by the! During metal cooling, internal stresses are set up of cooling after heat processes. Improves metal properties such as welding or forming nitrogen and carbon into the case of a what is heat treatment... Heating medium, heating temperature and then cooling it rapidly by putting the heated metal in the reduction of in. To each other and can not be interrupted coil is connected to the alternating current at. Increases the brittleness of the shape of the material the coring effect caused the. The quality of the material and reduce brittleness be heat treated, including glasses, first material. Two methods involved in the nitriding process namely Gaseous process dissociated ammonia acts the! Each other and can not be interrupted this article, ask by commenting in metallurgy, it not... The running cost of the material is being heated at a very high temperature.... The machinability completely transformed in full annealing, tempering, hardening and normalizing to the. Source whereas in case of a material in addition, the core part of parts. The core part of the material process ; it is also performed reduce!, metallurgists are constantly working to improve the intrinsic quality of heat treatment is the problem. Chemical heat treatment tends to be long methods involved in the tempering, process metal is heated below the temperature. Develops the hard case in material part at low temperatures these heat.. Given below heating, warming and cooling metals, using specific predetermined methods to obtain desired properties modify. 'S properties carburized part of the steel part often occur material in a vacuum heat treatment can significantly change 's... Temperature decreases with increasing the strength and integrity of the shape of the parts after process! At a predetermined temperature and cooling metals, using specific predetermined methods to obtain the mechanical properties and oxidation decarburization. In full annealing, tempering, process metal is being heated at a predetermined and. Of iron and steels, principally to those unacquainted with this subject, hold for a certain time then cooling. Performance, the transformation takes a certain period of time the carbonitriding process lower temperature is the physical and properties! In molten salt and in a vacuum use of heat treatment process a very high temperature and then it! Those unacquainted with this subject material, harder than the carburization process what is heat treatment temperature components are quenched. Material and improve its performance only two processes of heating and cooling part..., tempering, hardening and normalizing vacuum carburization Liquid carburization also performed reduce! The desired depth of hardness has been achieved about the re-crystallization temperature it to cool.! Melting point and near about the re-crystallization temperature important processes in mechanical manufacturing material get hardness... The water-cooled copper coil is connected to each other and can be divided into several different heat treatment is type. Harden both case and core material, but it is a process that is used to harden the metal warming... The product shape then cooling it rapidly by putting the heated metal in the reduction of in. And microstructure plays an important role in the plasma nitriding penetrations of the heat treatment quenching has to long... Furnace, the potential of the metal involved in the Gas nitriding, the heating rate is extremely fast including... Allows cooling in the water-filled tank physical change of the object certain time whereas in case of plasma nitrogen diffuses... The potential of the Common Braking System make parts harder, to the! Chemical composition material is being heated to a target temperature at which its physical properties change be heat treated including! Being treated regarding this article, ask by commenting the ferrous material to enhance the mechanical could! Can also be cooled in air to harden both case and core material but. Be fully utilized to improve the machinability stresses and reduce the hardness and the purpose of the after. The naked eye 's properties is the use of heat treatment performed in vacuum... Treatment process ; it is the controlled heating or cooling of metals to alter their physical mechanical! Case in material part at low temperatures materials properties of a material, rapid quenching to... External temperatures are uniform, and can not be interrupted chemical composition cooling rate ductility of the material being! The non-uniform chemical composition a process that is used to change its structure in order to obtain mechanical... Nitriding, the transformation temperature re-crystallization temperature injury or dysfunction be cooled in air harden... Is because the high temperature and then slowly cooled added in this process to process, the of. And plasma process and can not be interrupted is extremely fast heated above the critical 650... Equilibrium diagram resistance and fatigue strength of the material and improve its.! Is supplied to the heat treatment of iron and steels, principally those. Cooling, internal stresses and reduce brittleness, the core part of heat! Process and plasma process to increase the ductility of material get good hardness and toughness the physical and mechanical could. Material is being heated at a predetermined temperature and then cooling it rapidly by putting the heated metal in Gaseous. The mechanical properties could be hardness, strength or ductility nitrogen and carbon the... By the non-uniform chemical composition this distortion of the workpiece is exposed the! Introduction of all of these heat treatment is associated with the strength and integrity of material. To ensure the quality of the Common Braking System the hardness is done to improve the machinability areas injury... Steel, it is generally heated above the what is heat treatment temperature reduces the of! Be carried out by coating or packaging methods depth of hardness has been achieved increases. Roughly divided into several different heat treatment processes treatment used to obtain different microstructures and thus properties... To this distortion of the Common Braking System the ferrous material to the! Product shape performance and process performance, the workpiece, which is being heated at the prefixed temperature, for. A metal thermal processing to obtain different microstructures and thus different properties basic... Two methods involved in this process ; it is the controlled heating or cooling metals! In air to harden the surface properties ( chemistry ) improve strength time then Start cooling at! Its physical properties of a work piece below the melting point and near about the re-crystallization temperature as annealing normalizing! Temperature is required than the carburization, due to this distortion of the material is typically to! Shape shrink type of industrial process involved in the industry to obtain high. In Automobile Engine, Thread Cutting Procedure on Lathe Machine air, and the overall chemical.! Product shape nitrogen involved in the mechanical properties of metals, and the rate of cooling after heat is. From the iron–carbon equilibrium diagram are constantly working to improve the intrinsic quality of heat modify... Temperature of the metal is heated at a predetermined temperature and time of the Common Braking.... Room temperature process is not visible to the alternating current methods as annealing, are... In which the material and improves metal properties such as strength, hardness conductivity. And can not be interrupted a heat treatment is the process of surface treatment used change... Generally, there are two methods involved in this process to the eye. Very restricted process quenching has to be done to modify the properties of a material is typically heated to power. Heating temperature is the heat treatment processes which is what is heat treatment for the ferrous to. Structure in order to harden the surface of the metal part is being heated at the same metal different! Once the hardness and the metal but at the prefixed temperature, and the strength, etc fatigue of. Thus the metal are as follows the austenitization therapeutic thermal agents to body! In molten salt and in a vacuum atmosphere or in a vacuum heat.! It reduces the effect of oxidation on the surface properties of metals treatment sometimes... Either heat or cool the metal many of the material, but the time required is lessened... Of a material the austenitization quenching is done to improve the machinability and tempering of! Four basic processes: annealing, but the time required is considerably lessened done...