A kind of production method of manganese nitride product

Abstract

The invention discloses a method for producing a manganese nitride product. A material temperature rise stage or / and a cooling process at the end of the highest-temperature reaction stage are divided into two stages. More specifically, any one or two points exit as follows: 1) the material temperature rise stage is divided into two stages: an initial temperature rise stage and a continuous heating stage; 2) nitrogen is fed when the system reaches 650-700 DEG C in the initial temperature rise stage; 3) the cooling process at the end of the highest-temperature reaction stage is divided into two stages, when the temperature is higher than 650 DEG C, the cooling speed is 1-3 DEG C / min and the nitrogen pressure is kept at 0.4-1.0 MPa, and after the temperature is lower than 650 DEG C, the cooling speed is 3-10 DEG C / min, and the nitrogen valve is closed. The nitrogen content of the manganese nitride product produced by using the process is 8-12%, and the nitrogen content fluctuation of a single batch of products is smaller than + / - 0.5%.

Description

technical field [0001] The invention relates to a manganese nitride alloy smelting process, and specifically belongs to the technical field of ferroalloy metallurgical engineering. Background technique [0002] As we all know: "There is no steel without manganese". The steel industry's demand for manganese accounts for 90% to 95% of manganese production. Manganese is an important deoxidizer, desulfurizer and alloying element in the steelmaking process. Manganese can strengthen ferrite and refine pearlite, so it can improve the strength and hardenability of steel, so it can be used as an alloying element of steel. Manganese is mainly added to molten steel in the form of ferroalloy during the smelting process. In recent years, the role of nitrogen has been paid more and more attention. For example: 1. In multi-component stainless steel, nitrogen can partially replace nickel to form a stable austenite structure, improve the macrostructure of steel, and form nitrides with al...

AI Technical Summary

Problems solved by technology

The disadvantages of this method are: 1. Because electric heating is used throughout the nitriding of metal manganese, the energy consumption is high; 2. Due to the insulation layer and refractory materials in the vacuum furnace, the charging rate in the furnace is low, and the equipment is huge. It is difficult to increase the pressure; 3. Since the furnace door cannot be opened during cooling (to prevent high-temperature oxidation of manganese), the cooling time is long and the efficiency is low; 4. The furnace body must be cooled every time before it can be charged again, resulting in waste of energy for heating up the furnace body

Also due to insufficient reaction time, the content of metal manganese and nitrogen in different positions in the reaction vessel is also different, and the general fluctuation range is 4% to 7%.