Handan Qiming Carbon Co., Ltd
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Isostatic Pressing Ceramics, Isostatic Graphite, Isostatic Cold Isostatic Pressing Rubber Sleeve
May,05,2023

Isostatic ceramics, isostatic graphite, cold isostatic rubber cover molds, complete sets of designs, isostatic molding molds with complex shapes, precision molding molds, and fixtures. Sealing structure design, precision molding design, elastic mold hardness selection, and fixture design ensure molding accuracy. The isostatic rubber sleeve mold made of special polyurethane material has the advantages of rolling type in terms of performance and cost performance! The polyurethane polymer material specially developed for isostatic pressing molds has the characteristics of good plasticity, good elasticity, oil resistance, water resistance, and oxidation aging resistance. Embodied in isostatic pressing production, it means precise molding, smooth surface, and long service life. According to the purpose, there are targeted solutions, including the design and manufacture of rubber sleeves, tooling, and lifting fixtures. Of course, the so-called isostatic pressing molds that ordinary polyurethane products companies use to make rough conventional polyurethane materials cannot realize these advantages. According to Pascal's principle, pressure is applied to the rubber mold through a liquid medium such as water, and the pressure in all directions is equal. In this way, the extruded powder particles are not oriented in the filling direction in the mold, but compressed in an irregular arrangement. Therefore, although graphite is anisotropic in crystallographic properties, isostatic graphite is isotropic as a whole. In addition to cylinders and rectangles, molded products also have shapes such as cylinders and crucibles.

Isostatic pressing ceramics, isostatic graphite, isostatic cold isostatic pressing rubber sleeve

Isostatic presses are mainly used in the powder metallurgy industry. Due to the needs of high-end industries such as aerospace, nuclear industry, cemented carbide, and high-voltage electromagnetics, isostatic pressing technology has developed rapidly, and can manufacture working cylinder inner diameter, height, and maximum working pressure cold isostatic pressing machines. At present, the maximum specification of the cold isostatic press used in the carbon industry to produce isostatic graphite is Φ× and the maximum working pressure. When isostatic graphite is used in the fields of semiconductors, single-crystal silicon, and atomic energy, the requirements for purity are very high, and impurities must be removed by chemical methods before they can be used in these fields. The usual way to remove impurities in graphite is to put the graphitized product into a halogen gas and heat it to about 2000°C, and the impurities will be halogenated into low-boiling halides to volatilize and remove. Almost all impurity elements in graphitized products can be removed by halogenation with chlorine gas. The exception is boron, which can only be removed by fluorination. Halogen gases used for purification include chlorine, fluorine, or halogenated hydrocarbons, which can be decomposed to produce these gases under high-temperature conditions, such as carbon tetrachloride (CCl4), dichlorodifluoromethane ().

Graphite chiller_天津Graphite chiller_The role of graphite chiller

Czochralski monocrystalline silicon thermal field and heater for polycrystalline silicon ingot furnace

Isostatic pressing ceramics, isostatic graphite, isostatic cold isostatic pressing rubber sleeve

In the thermal field of Czochralski monocrystalline silicon, the isostatic graphite components include more than 30 types such as crucibles, heaters, electrodes, heat shields, seed holders, rotating crucible bases, various discs, and heat reflection plates.

Among them, 80% of isostatic graphite is used to make crucibles and heaters. In recent years, the diameter of monocrystalline silicon rods has become larger and larger, and the production of silicon wafers has increasingly become mainstream.

Correspondingly, the diameter of the heating zone of the single crystal furnace is mostly. The diameter of the graphite crucible in the furnace is to protect the quartz crucible placed in it.

There is almost no glass phase in 95% isostatic-pressed porcelain. During metallization, depending on the action of the activator and the porcelain interface, a sufficient amount of glass-like substance is formed to penetrate the molybdenum layer, so a higher firing temperature is required. Add a certain amount of active oxides, the glass-like substance formed by them, and manganese oxide has a low melting point, low viscosity, good wettability to molybdenum, and a firm combination with porcelain. At the same time, manganese is also combined with glass to increase the expansion coefficient of the glass phase, which is closer to that of molybdenum and porcelain, thereby reducing interfacial stress and improving product performance.

In the ceramic metallization process, the following aspects are controlled, which not only makes the metalized ceramics produced by the existing isostatic pressing process 95% dense, but also has high volume density, low porosity, uniform microstructure, higher strength, and better regularity. so wait.  , and can ensure that the metallization layer is well combined with the ceramic, the performance index is high, and the quality is reliable and stable.

(1) By controlling the particle size of the metal powder, the metal ash powder is deposited on the ceramic body as closely as possible, thereby making the metalized layer dense.

(2) The reasonable combination of metal powder particles and ceramic crystal phase particles makes the metal slurry form a tight bond with the ceramic body during the firing process.

(3) The active agent is used to promote the proper reaction and mutual penetration of the metalized layer and the ceramic, to achieve a firm bond between the metalized layer and the ceramic, and to ensure that the metalized ceramic achieves a high tensile strength when sealed.

(4) Ceramics with different processes and contents must have different metallization formulas and processes to ensure the optimal technical indicators, high stability, and reliability of ceramics after metallization.

(5) The primary metallization firing temperature should match the ceramic firing temperature and ceramic crystal phase structure.