(1) screening method. Advantages: simple, intuitive, low equipment cost, often used for samples greater than 40um. Disadvantages: The result is greatly affected by human factors and sieve deformation.
(2) microscope (picture) method. Advantages: simple, intuitive, can be traced analysis, suitable for narrow distribution (large and small particle size ratio less than 10:1) of the sample. Disadvantages: poor representation, analysis of wide distribution scale of the sample is more troublesome, can not analyze less than 1um of the sample.
(3) Settlement method (including gravity settlement and Lixin settlement). Advantages: gradual operation, continuous operation of the instrument, low price, good accuracy and repeatability, a wide scale of testing. Disadvantages: the test time is long, the operation is more complicated.
Application of white corundum wear-resistant material in aviation industryIn the 1970s, more than 500 parts of wear-resistant materials were thermal sprayed in an aviation turbine engine, and more than 2,000 parts of wear-resistant materials have been thermal sprayed in modern new turbine engines, about 3,000 places. The thermal spraying of wear-resistant materials on parts has become an indispensable and important process technology in the aviation industry.Like white corundum and other wear-resistant materials in the aviation industry is the earlier application of thermal spraying technology coating department, but also the application of thermal spraying technology more and more successful high-tech fields. With the continuous progress of thermal spraying technology, such as the continuous development of high-performance coating materials, low-pressure plasma spraying, high-speed flame spraying technology has come out one after another, and the coating quality has made a qualitative leap. The application of thermal spraying technology in the aviation industry is also more and more extensive.Material thermal spraying parts of about 500, and modern new turbine engine for wear-resistant material thermal spraying parts have reached more than 2000, about 3000 places. The thermal spraying of wear-resistant materials for parts has become an indispensable and important process technology in the aviation industry.Like white corundum and other wear-resistant materials in the aviation industry is the earlier application of thermal spraying technology coating department, but also the application of thermal spraying technology more and more successful high-tech fields. With the continuous progress of thermal spraying technology, such as high-performance coating materials are constantly developed. Low pressure plasma spraying, high-speed flame spraying technology has come out one after another, and the coating quality has made a qualitative leap. The application of thermal spraying technology in aviation industry is also more and more extensive.
Structural characteristics of white corundum frit:1, white corundum frit upper layer: also called cap, is divided into two parts of the upper base, the upper structure is tight and robust, there are porous flake crystals, the base has cylindrical holes of fine crystals. White corundum frit structure characteristics2, white corundum frit core: the structure of the core is also tight and robust, and the porosity is larger. It should be noted that the core of the white corundum frit has many glassy crystals with holes and different shapes, and the main component of the crystals is -AI203 after detection.3. The middle and lower part of the white corundum frit: the crystal shape of the base is coarse, but the structure is still tight, and the color is white and good.4, white corundum frit edge: the middle and lower crystals are not as tight as the upper two layers, slightly loose, and the crystals are mostly columnar or granular, with pores and microcrystalline crystals at the edge.
