Nitride alloy production process technology innovation
Cater Parts,Cater Engine Parts,Cheap Cater Parts,Cater Forklift Parts JINING SHANTE SONGZHENG CONSTRUCTION MACHINERY CO.LTD , https://www.sdkomatsugenuineparts.com
July 13 16:01:00, 2024
Anyang City, Dingxing Metallurgical Refractories Co., Ltd. Chairman Wang Zhiming
Nitride alloys in our country's industrial applications continue to expand, the real time for large-scale popularization and application is also in the past 10 years. From monocrystalline silicon, polysilicon, high-end ceramics, to high-grade refractory materials, high-nitrogen steels, high-strength steels, special steels, and aviation and aerospace fields, the enhancement of nitrided alloys has been increasingly recognized and promoted. .
However, our country's nitrided alloy industry started late relative to developed countries. Taking silicon nitride alone as an example, China's export of high-grade silicon nitride is 50,000 to 60,000 yuan per ton, while imported silicon nitride used for the production of monocrystalline silicon and polysilicon is as high as 60 to 80,000 yuan. Ton. The price difference is more than 10 times. Therefore, China's nitrided alloy production process does require continuous innovation and development to gradually shorten the technological distance with developed countries.
At present, nitrides such as silicon nitride, silicon nitride iron nitride, manganese silicon nitride, chromium nitride, and vanadium nitride have reached a wide range of applications in the iron and steel smelting industry. Such as silicon nitride, silicon nitride iron powder added to the blast furnace mud, so that the mud gun strength and opening performance to significantly improve the number of running iron to reduce the need to meet the needs of large-scale blast furnace has become a modern large-scale blast furnace gun Indispensable key component of mud; in the steelmaking industry, granular nitrided alloy is an efficient nitrogen-promoting agent. It enters the molten steel and precipitates, solid solution and precipitation strengthens, which significantly improves the strength of steel and strengthens the low cost. . The gradual popularization of nitrided alloys is of great significance to the cost reduction and efficiency increase of steel production enterprises, and the application prospect of nitrided alloys is optimistic.
In the production of vacuum nitrided alloys, there are many different production processes. Taking silicon- and manganese-based nitriding processes as an example, most companies now use silicon nitride bonded silicon carbide pallets as kiln furniture, and alloy materials that require nitriding are layered on top in powdered form and fed into the furnace. Nitriding reaction is performed in a vacuum nitriding furnace. This kind of process has great labor intensity, many damages to the pallets, low heat production, and high production costs. The innovative process is that the alloy raw materials are pressed and formed, and after drying, the kiln car is directly loaded into a vacuum furnace for nitriding. The new process eliminates the use of pallets, saves operational equipment costs, reduces labor intensity, increases heat production, and reduces overall production costs.
Innovative production process:
one, Process flow:
Ingredients - Mixing - - Auxiliary - Molding - Drying - Drying standby - Kiln loading - Nitriding furnace - Nitriding - Forced cooling - Milling - Milling (grain) --- storage
two, crafting process:
1, the mix of ingredients
According to the proportion, the raw materials, additives, binders and water are mixed and the reaction is performed;
2, extrusion molding
Mixed raw materials must be refrigerated for more than 12 hours before high-pressure extrusion molding;
3, loading and drying
After extruding, it is directly loaded on the drying car and enters the far-infrared (or gas) tunnel kiln for drying;
4, loading into the furnace
The semi-finished product is loaded on a kiln car and pushed into a vacuum furnace for nitriding reaction;
5. Nitriding reaction
According to the set heating curve, the computer automatically controls the nitriding process;
6, cooling out
Nitriding reaction is completed, forced cooling out of the furnace;
7, the powder into storage
According to the order requirements milling, grain, testing, packaging, storage.
three, Production equipment:
Planet forced mixing mill, 100 tons hydraulic press, far infrared drying tunnel, vacuum nitriding furnace, jaw crusher, flexible milling machine, automatic bagging machine, measuring equipment, electronic control equipment.
four, Product quality indicators: (by si3N4)
N=37% si=60% Fe=0.3% Ai=0.4% Ca=0.12% O=1.23%
It is worth noting that in the process of nitriding and heating, there is often a situation where the temperature rises too quickly and cannot be controlled. Eventually, the phenomenon of silicon deposition occurs, resulting in adhesion of the pallet and the kiln car, incomplete nitriding, and unqualified products. as a result of. The key to solving this problem is the accumulation of experience of operators, that is, the setting of warming curve and flexible operation control. We must respect science, respect talents, and respect practice. Only when management is in place can we receive the expected results.