Process method for preparing wear-resisting extrusion roller sleeve through centrifugal casting

Abstract

The invention relates to a process method for preparing a wear-resisting extrusion roller sleeve through centrifugal casting, and belongs to the field of metal based composite material. The method includes the steps that firstly, an annular blank with a framework is prepared; and secondly, the blank is spliced to be placed into a centrifugal machine die, metal liquid pouring is carried out, and the wear-resisting roller sleeve is obtained. A composite zone of the roller sleeve is composed of two different ceramic particles, wherein the outer layer ceramic particle is the ceramic particle with good iron liquid wettability, and the inner layer ceramic particle is the oxide ceramic particle. By means of the method, the framework is placed into the blank, the blank strength is improved, containing is facilitated, different ceramic particles are selected, the blank cost is reduced, the roller face composite effect is improved, and the service life of the roller face is greatly improved.

Description

technical field [0001] The invention relates to a process method of centrifugal casting for preparing a wear-resistant squeeze roller sleeve, which belongs to the field of metal matrix composite materials. Background technique [0002] As a high-efficiency and energy-saving crushing equipment, roller presses have been widely used in industries such as cement building materials, mine crushing and grinding operations. When the roller press is working, a huge extrusion force is generated to crush the material, and the roller surface and the material generate strong friction, and are subjected to the impact force of the material, and the roller surface is extremely easy to wear. Traditional extrusion rollers are difficult to meet the needs of the current market due to their short service life, difficult manufacturing process, high cost, and long repair time. Ceramic-metal composite materials have high toughness of metal materials and high wear resistance of ceramic particles. ...

AI Technical Summary

Problems solved by technology

However, the preparation process of this method is complicated, the equipment requirements are high, and the manufacturing cost is increased.

Chinese invention patent CN102211048A discloses a medium-speed coal mill roller sleeve with metal-ceramic composites. The method is to bond the ceramic particles to each other to form a network, and to compound the cast metal liquid as a whole. However, this method has the following disadvantages. First, its The pore casting infiltration produced solely by the mutual bonding between ceramic particles limits the thickness of the molten metal casting infiltration, so that the thickness of the ceramic-metal composite layer is very thin, and the dispersion degree between the ceramic particles is small, and the metal between the ceramic particles It cannot effectively play a supporting role. During the wear process, the ceramic particles are easy to peel off, and the wear resistance is greatly reduced; secondly, this method bonds the ceramic particles to each other to form a ceramic layer with a network structure, and then infiltrates the entire ceramic layer, casting During the process, the entire ceramic layer is easily unusable due to a certain part of the defect or the collapse of the molten metal impact, and the yield is greatly reduced; in addition, the grinding roller body is connected with the high chromium alloy and ceramic particles by casting. Due to the thermal expansion of the three materials The coefficient and thermal conductivity are very different. During the cooling or heat treatment process of the grinding roller after casting, the metallurgical combination of its high chromium alloy, ceramic metal composite area and the grinding roller body will easily cause cracks at the joint surface to spread throughout the grinding roller. Expansion, increasing the likelihood of roll cracking

Chinese invention patent CN103418790 discloses a metal-ceramic composite wear-resistant product and its preparation method, which is characterized in that ceramic particles and metal powder are uniformly mixed with additives to obtain a cermet particle prefabricated part made of mixture and metal powder, which is sintered at high temperature Metal-ceramic composite wear-resistant products formed after heat treatment. This method uses additives to evenly mix ceramic particles and metal powder. However, after the metal is melted after sintering, the ceramic particles will float upward due to their specific gravity being smaller than that of the metal powder, resulting in uneven distribution of ceramic particles. , and the structure performance after sintering is poorer than that of smelted metal crystallization

Chinese invention patent CN1367270A discloses a production process of centrifugal casting high wear-resistant alloy cast iron composite anti-friction roll ring, which is characterized in that the outer layer of the composite anti-friction roll ring contains vanadium and a variety of alloy cast iron with a small amount of elements, and the inner layer is high-strength nodular graphite Cast iron, due to the vanadium and a variety of alloys with a small amount of elements, the grinding roller produced by this method has higher hardness and stronger wear resistance, but because there are many types of alloys and the addition amount is very small, it is difficult to accurately control the alloy when smelting Its composition, and the hardness of the outer layer alloy has certain limitations, too high hardness will lead to a great decrease in the toughness of the outer layer alloy, affecting the performance

Chinese invention patent CN103736549A discloses a preparation method of metal-based ceramic composite material grinding rollers for vertical mills. The metal-based ceramic reinforcement material used in this method is sintered from 10-40% corundum and 60-90% iron powder. The chromium alloy liner and the ceramic liner, the roller sleeve and the grinding roller base are cast together through molten steel. Since this method uses the sintering method to prepare the composite layer, it is difficult to make the ceramic particles due to the large difference in specific gravity between the ceramic particles and the iron powder. Mix evenly with iron powder, and after the molten iron is melted, the ceramic particles will float on the surface of the molten iron. After casting into the mold, the distribution of the ceramic particles will be extremely uneven, and the structure after sintering is not as good as the metal structure formed after the metal is completely melted and crystallized. The cast molten steel consolidates the roller cover and the grinding roller matrix into one, and the cracks during use can easily spread throughout the grinding roller

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