Tavlama Ä°ÅŸlemleri Nelerdir?
What Are Annealing Processes?
Annealing is a heat treatment method improving the material and its workability, done below eutectoid temperatures.
Adds features such as softening, reducing the stresses in the cast, forged and rolled materials, increasing the workability and reducing the fragility to the material. Thus, the material possesses the required mechanical properties at the production stage or at the end of the production. Annealing can also be applied to non-ferrous alloys as well as to steel.
The annealing processes are divided into 3 groups according to the type of atmosphere that the equipment can provide.
Annealing in open atmosphere furnaces;
The advantage of this process is that it is a lower cost process than other processes; however, since the atmosphere of the process is air, the material surface is adversely affected by oxygen and other elements present in the air. Oxidations (oxide layers) are formed on the material surface, and this causes coloring on the surface of the material.
Annealing in atmosphere controlled furnaces; (Bright Annealing Processes)
In this process, the furnace atmosphere is created in a controlled way. In this process where nitrogen, helium or hydrogen is used as the furnace atmosphere, since oxygen and other unwanted gases are not present, the surface of the material appears very bright after the process.
Annealing Processes in Vacuum Furnaces;
(Bright Annealing Processes)
These processes are carried out in vacuum furnaces. The heating and waiting steps in the process are carried out under vacuum and in the created atmosphere. The biggest advantage of atmosphere controlled furnaces compared to bright annealing is that the heating is very controlled and it offers fast cooling with high pressure control.
Normalizing Annealing
In this process, the steel is heated to 830-950 degrees depending on the amount of carbon in the steel, and then slowly cooled in the calm air. According to the state of the material before the process, the properties that the material will gain as a result of normalizing vary. The main purpose of the process is to eliminate the unwanted properties which were given to the material by pre-process operationssuch as forging, casting and rolling. (Thinning of the coarse grain and removal of residual stresses, etc.)
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Soft Annealing
In this process, the steel is heated to below eutectoid temperatures, depending on the section's thickness, the steel is left at this temperature for a certain period of time, and the process is done. Its greatest advantage is reducing the hardness of the steel and increasing its workability and formability.
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Stress Relief Annealing
In this process, the steel is heated to below eutectoid temperatures and depending on the section's thickness, it is kept at this temperature for a certain period of time, and the process is done. Residual stresses in the material are reduced or eliminated by welding after the processes, in which residual stresses can occur, such as machining and plastic shaping
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Demagnetization Annealing
It is a process of reducing magnetic properties of steels whose magnetism properties are not needed or needed to be at low rates, by leaving them at a certain temperature for a certain period of time
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Spheroidizing Annealing
It is the process achieved by transforming the cementites present in the perlite phase into spherical morphology as a result of keeping the steel at a certain temperature and time in order to increase the workability and shaping capacity of the steel.
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Aluminium Annealing
It is a process applied to eliminate stresses in aluminum manufacturing methods (casting, forging, extrusion, etc.). In addition, as a result of annealing processes applied to aluminum, the hardness values decrease, so the workability and shaping capacity also increse.
Other Annealing Processes;
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Recrystallization annealing
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Ferritization annealing
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Hydrogen embrittlement relief annealing
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Diffusion (Homogenization) annealing
Annealing Processes in Önerler
Firmamızda tavlama iÅŸlemleri için atmosfer kontrollü kamara tipi fırınlar, açık ve atmosfer kontrollü tav fırınları, vakum fırınları kullanılmaktadır.
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Firmamızda açık, koruyucu ve vakum atmosferlerinde gerçekleÅŸtirilen tavlama iÅŸlemlerinin tümü yapılmaktadır.
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Åžarj kapasiteleri 100 - 2000 kg 'a kadar olan çeÅŸitli fırınlarla müÅŸterilerimize esnek bir ÅŸarj miktarı fırsatı sunmaktayız.
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Fırınlarımızın tümü Alman menÅŸei olup konusunda dünya öncüsü olan IPSEN markadır.
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Fırınlarımızda bulunan proses kontrol cihazları ile proses için sürekli kontrol altındadır ve proseslerin verileri kayıt altında tutulur.
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Firmamızın kurulduÄŸu 1967 yılından beri, 50 yıllık bir süre boyunca yapmakta olduÄŸumuz tavlama iÅŸlemi konusunda, tecrübe, uzman personelimiz ve son teknoloji ekipmanlarımız ile müÅŸterilerimize en iyi kaliteyi sunmaktayız.
Benefits of The Processes
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Malzeme bünyesindeki gerilim düÅŸer
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Malzeme iç yapısı iyileÅŸtirilir
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Manyetik özellikler iyileÅŸtirilir
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DüÅŸük atıklık
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Kaynaklı malzemelerde iyileşme
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Gerek duyulan sertliÄŸe indirilir
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Temiz yüzey (parlak tavlama)
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İşlenebilirliğin arttırılması
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Şekillendirme kabiliyetinin arttırılması
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The stress in the material decreases
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Internal structure of the material is improved
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Magnetic properties are improved
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Low dimensional change
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Improvement in welded materials
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Reducing to the required hardness
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Clean surface (bright annealing)
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Increasing workability
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Increasing shaping capacity
Risks of The Processes
Especially in annealing processes performed in open-atmosphere furnaces, oxide layer and oxidation can be observed and also color changes may occur on the surface of the material. After normalizing, the hardness of the material can increase (due to the formation of martensite and bainite phases near the surface) in high-hardness and relatively high-alloyed steels, which can affect the workability adversely. Additionally, during the normalizing process carried out in open atmosphere furnaces, a decarburization layer can be observed on the surface.
In bright annealing processes carried out under shielding gas, since the atmosphere composition is not well controlled, embrittlement or brittleness may be observed in the material.
Because of failure to correctly enter the furnace parameters, the properties of the steel can be adversely affected in vacuum annealing (bright annealing) of high-alloy steels (stainless and tool steels) due to the evaporation of certain elements on the material surface.
Heat Treatment
BOSB Turuncu Cad. No: 12, 16120
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Steel Supply
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