Chromium carbide is a high melting point inorganic material with good wear resistance, corrosion resistance and oxidation resistance in high temperature environment (1000~1100). Due to its special high temperature properties, it is mostly used as a thermal spray material for metal surface protection processes and as an additive in the carbide industry. At present, the production of chromium carbide process has metal chromium powder direct carbonization, chromium oxide aluminum thermal self-diffusion carbonization, chromium oxide carbon thermal reduction carbonization three major processes, the following together to understand the preparation method and process of chromium carbide!

The direct carbonization process of metal chromium powder is to use a high-rise apartment furnace or an induction heating furnace to heat up to 1500~1700 in a hydrogen stream, maintain lh to make chromium carbonization reaction, and cool to manufacture chromium carbide. Due to the high reaction temperature, heating in a hydrogen stream is very dangerous, the process parameters are difficult to control, the product quality is unstable, the temperature is difficult to reach, and large-scale production cannot be achieved in industry. Because the carbonization process cannot remove the metal impurities in the raw material chromium, the method requires high purity of the raw material chromium, high production cost metal chromium and chromium carbide hardness, raw material preparation and finished product processing need to be crushed with a hard crusher, processing costs are high.

Chromium oxide aluminum thermal self-diffusion carbonization process is to use cr2o3, cro3, aluminum powder and carbon black in a ratio of 1:0.73:0.73:0.25 as raw materials, put the prepared raw materials into a mixer and mix for 6h, and put them into a graphite crucible. The pre-pressurized pressure is 5mpa. This method as the upper plane ignition source of tungsten wire has high cost, and its industrial application is not yet mature, and it is still in the laboratory stage. In addition, the chromium oxide thermite carbonization method uses the principle of thermite reaction, which is the heat source for carbonization reaction through its heat, but its reaction temperature is also difficult to control, the requirements for raw materials are also high, there is incomplete carbonization or over-carbonization phenomenon, thermite reaction a large number of heat, accompanied by too many risk factors.

The manufacturing cost of the chromium oxide-carbon thermal reduction carbonization process is relatively low, but because the method is a solid-solid reduction reaction, the powder mixture such as high-pressure pressing or ball mill is uniform and close, and the amount of reducing agent and chromium dioxide is strictly required. Otherwise, some problems will easily occur. The main reason is (1) the residual amount of cr2o3) exceeding the oxygen reference value due to incomplete reaction or the residual amount of carbonaceous substances exceeding the free carbon reference value), and the quality of the product is unstable.) When the reduction reaction, the amount of reducing agent is small, in order to speed up the reaction speed, the reaction temperature needs to be higher than 1480, the reaction temperature is higher than 1500 is prone to excessive reduction, easy to generate chromium carbon semi-melting alloy, the reaction temperature control range of the method is small. On the basis of one-step carbonization process, a two-step carbonization process is proposed, and the experimental results are good, but the process is long, and there is no production example of large-scale application. Technical realization elements:

The technical problem to be solved by the invention is that the traditional chromium carbide manufacturing method is difficult to produce in large quantities, and the quality of the manufactured chromium carbide product is unstable.

In order to solve the technical problem of the present invention, the technical means used is to uniformly mix the raw materials of each weight ratio, press forming, drying, to obtain the forming, heating and cooling the forming in a nitrogen atmosphere to obtain, the blending amount of carbonaceous powder is controlled according to the relationship of mass 100% of carbonaceous powder =(1-mass of cr in raw chromium compound (3/4) mass of c in chromium carbide of product) mass of chromium carbide of product).

Here, in the above-described method for producing chromium carbide, the raw materials are mixed in a ratio by weight of 100 parts by weight of the chromium compound, 25 to 35 parts by weight of the carbonaceous powder, 10 to 50 parts by weight of the iron powder, and 5 to 20 parts by weight of the binder.

The raw materials are preferably blended in an amount of 100 parts by weight of the chromium compound, 26 to 33 parts by weight of the carbonaceous powder, 25 to 30 parts by weight of the iron powder, and 8 to 15 parts by weight of the binder.

The above is the preparation method and process of chromium carbide, if you need to know more, please feel free to contact us!