Ferrochrome nitride is also called ferro chrome nitride or nitrided ferro chrome. It is a ferroalloy material mainly composed of nitrides such as Cr N, Cr2N, and Fe4N. It is also possible to generate compound nitrides (Cr, Fe) 2N (1-x) of ferrochrome. The main factors affecting its phase composition are nitriding medium and nitriding temperature. The main use of ferrochrome nitride is to produce corrosion-resistant and other special nitrogen-containing steel.
Features of ferrochrome nitride
- Stable nitrogen content
- High density
- High alloy absorption rate
- Melting point: about 700 degrees Celsius
- Ferrochrome nitride can partially replace nickel elements and reduce the production cost.
Application of ferrochrome nitride
Ferrochrome nitride is widely applied in electric furnaces and oxygen converters to smelt nitrogen-bearing steel. As a kind of alloy material，it plays a key role in the smelting and production of special steel such as stainless steel, heat-resistant steel, corrosion-resistant steel, alloy steel, etc.
Nitrogen is an austenite-forming element. It is added as a component of chromium-manganese and chromium-manganese-nickel stainless steel to replace the shortage of nickel.
Research shows the role of nitrogen in expanding the austenite region is about 30 times that of nickel. At present, adding nitrogen to the production of nickel-containing austenitic stainless steel can partially replace the precious metal nickel and bring considerable economic benefits. Also, nitrogen can make steel have high strength and high corrosion resistance and can maintain the plasticity of steel at a good level.
China and India are the largest producers of nitrogen-containing corrosion-resistant steel. The production of this type of steel continues to increase and currently accounts for 10% of the total global steel production. In contrast, in Asia, it accounts for about 20% of production. To meet the demand worldwide, ZHENXIN supplies a full range of nitride alloys including silicon nitride, ferro silicon nitride, ferrochrome nitride, silicon manganese nitride.
The chemical component of ferrochrome nitride
Standard chemical composition
|Chemical formula||Cr Min||N Min||C Max||Si Max||P Max||S Max|
Approximate chemical composition of ferrochromium nitride, %
Other-standard chemical composition
- Cr 60-65%min, N 8-10%, C 0.1%, Si 1.5-2.5%, P 0.03%max, S 0.04%max.
- Cr 60-65%min, N 8-10%, C 0.06%, Si 1.5-2.5%, P 0.03%max, S 0.04%max.
- Cr 60-65%min, N 8-10%, C 0.03%, Si 1.0%max, P 0.03%max, S 0.04%max.
Production and delivery standard of ferro chrome nitride
Sampling and sample preparation is carried out following the method of ferrochrome.
- Class A is applicable to seed fusion products after nitriding, and its nitrogen content does not include the adsorbed nitrogen content.
- Class B is suitable for fixed nitriding alloy.
- The content of chromium, nitrogen, phosphorus, carbon, and sulfur must be determined for each furnace.
- After negotiation between the supplier and the buyer, the B products with a silicon content of not more than 3.0% can be supplied.
- When there are special requirements for chemical composition, the supplier and the buyer shall negotiate.
|Natural property||The ferrochrome nitride is delivered in blocks, and the weight of each piece shall not exceed 5kg. The number of high-nitrogen ferrochromium blocks smaller than 10mm×10mm shall not exceed 10% of the total weight.|
|Physical condition||The interior and surface of ferrochromium nitride shall not contain significant non-metallic inclusions. The surface and interior of the solid nitriding alloy shall not have an obvious molten state.|
|Packing||According to the request of the buyer, it can be packed in bulk or ton bags|
|Specialties||If the buyer has special requirements, it can be negotiated with the supplier.|
Preparation of ferro chrome nitride
The standard nitrogen content of ferrochrome nitride products is 3.0% to 5.0% in China. In the production of nitrogen-containing steel, a vacuum resistance furnace is used with the solid nitriding production process.
Solid-phase nitriding uses nitrogen or ammonia as the nitriding raw material. The nitriding reaction occurs in a vacuum induction furnace or a resistance furnace. This method is generally combined with vacuum smelting of ferrochromium. After the vacuum decarburization is completed, nitrogen is passed into a vacuum furnace or induction furnace for nitriding treatment. The ferro chrome nitride produced by this method has a high porosity. Remelting ferrochromium nitride can densify the alloy, but the nitrogen content in the remelting stage will be reduced by 2% to 2.5%.
Another practical method of preparing the ferro chrome nitride is Self-propagating high-temperature synthesis(SHS). It is an alternative way to vacuum heating method in the production of high-purity, high-strength, and crossion-resistant ferro chrome nitride. The main feature of self-propagating synthesis is to fully combine the high heat generated by chemical reactions between elements to synthesize high-melting, high-performance materials in a short time. Self-propagating synthesis technology is a process that integrates material synthesis and sintering. The formation of combustion structure occurs in the self-propagating high-temperature synthesis reaction process. The macro-dynamics of structure is the link that connects the combustion process and the structure formation process.
The self-propagating high-temperature combustion process is divided into four stages
- The rapid expansion stage of the combustion reaction zone
- The steady-state combustion stage
- The deceleration synthesis stage
- The post-combustion stage after the combustion wave passes