Metal deoxidation, also known as deoxidation, is a metallurgical process aimed at improving the quality of materials. It allows you to recover iron from oxides and helps remove oxygen — harmful admixture, which has a negative effect on the mechanical properties of steels and alloys. The term “steel deoxidation” is used in narrow circles of metallurgists and is synonymous with the term “metal recovery”.
Methods for deoxidizing steels and alloys
Deoxidation is carried out by exposing the metal to elements that have a higher ability to react with oxygen than the base metal. This makes it possible to effectively bind oxygen and remove it from the material. This approach ensures stable mechanical and physical properties of steels and alloys.
Metals are recovered using one of the following methods:
- Precipitatory deoxidation. This method involves the use of substances such as silicon, aluminum, and manganese, which have a high affinity for oxygen. They react with oxygen to form oxides that are removed from the melt.
- Electroslag remelting (ESP). This is a method for cleaning steels and alloys from non-metallic inclusions, such as sulfur, by melting material in a slag bath.
- Extraction or diffusion deoxidation. Here, the amount of oxygen in the metal is reduced due to the effect of slag; chemical elements such as carbon, silicon, and aluminum are used as deoxidizers.
- Vacuum-carbon deoxidation. This process involves the purification of metals from oxygen under vacuum conditions, where carbon It has pronounced oxidizing properties.
- Treatment with synthetic toxins. This method is used to reduce the amount of sulfur and oxygen in the material. Deoxidation takes place in an arc furnace using slag containing Al2O3 and CaO.
The deoxidation of precision alloys is important for ensuring the high quality and accuracy of products made from these materials. The oxygen remaining in the alloy structure can cause the formation of pores and other defects in the metal structure, which can degrade its mechanical and physical properties.
Classification of steels by deoxidation method
Steel can be classified according to its degree of deoxidation, which affects its mechanical properties and ease of processing:
- Calm. The full degree of deoxidation has been carried out. It has a uniform chemical composition throughout the workpiece and, therefore, the same properties throughout the ingot. After casting, it is not prone to the formation of gases during solidification.
- Half-calm. Moderately deoxidized condition. It requires additional processing, as gas bubbles remain in the upper part of the ingot. Such defects are usually eliminated during the rolling process. An example of semi-quiet steel is an alloy 08PS.
- Boiling. Weakly deoxidized state, like a grade alloy 08KP. It has an uneven chemical composition across the cross section, but is very popular in various industries due to its low cost.
Proper deoxidation reduces the likelihood of undesirable defects in products and ensures increased reliability of products made from precision alloys.
Alloys produced at PZPS
At the PZPS precision alloy smelting It is carried out in vacuum furnaces, so deoxidation is also carried out in vacuum, which makes it possible to obtain high-quality precision alloys:
- with specified elasticity properties (17HNGT, 36NHTYU, 40KHNM);
- with a given TCLR (29NK, 36N, 42N);
- magnetically solid (EP-298, 13NHM);
- magnetically soft (27KH, 49K2FA-VI, 50N, 50NP, 79NM, 80NM, 81NMA);
- with high electrical resistance (X15YU5, X15N60N, X20N80N, X23U5, X23YU5T).
In addition to smelting steels and alloys, our company provides a number of production services — from the development of new technological solutions to the production of industrial batches of products. For cooperation and acquisitions precision materials with the required physical and mechanical properties, please call +7 (812) 740-76-55 or leave a request on our site. Our experts will contact you and answer your questions in detail.
