I. for Czochralski single crystal silicon thermal field and polycrystalline silicon ingot furnace

In the thermal field of Czochralski silicon, there are about 30 kinds of isostatic pressure graphite parts, such as crucible, heater, electrode, heat shield plate, seed crystal holder, base for rotating crucible, various round plates, heat reflecting plates, etc. Among them, 80% of isostatic graphite is used to make crucibles and heaters.

In the manufacturing process of solar cell polycrystalline silicon wafer, the first step is to melt and cast the polycrystalline silicon fragment into polycrystalline silicon ingot. The heater of ingot furnace needs to be made of isostatic pressure graphite.

II. EDM electrode (i.e. for EDM)

EDM with graphite or copper as electrode is widely used in metal mold and other processing fields. The electrode materials are required to have the following characteristics in the EDM process: ① high speed of EDM; ② less consumption of electrode length; ③ less loss of electrode angle; ④ good roughness of machined surface; ⑤ less concave convex of machined surface. (simplified, the word "etc" has been removed)

Compared with copper electrode, graphite electrode for EDM has the following advantages: ① lighter than copper, easy to handle, only 1 / 5 of the weight of copper in the same shape; ② easier to process; ③ less stress and thermal deformation due to machining; ④ melting point above 3000 ℃, small thermal expansion coefficient, and little deformation due to the heat generated by EDM. However, there are some disadvantages of graphite electrode, such as dust easily produced in cutting and graphite itself is easy to be lost.

III. graphite mold for continuous casting of non-ferrous metals

It is very common to produce non-ferrous metal plates, tubes and bars by continuous casting and rolling because it can simplify the casting process, improve the qualified rate of products and homogenize the product structure. At present, continuous casting is mainly used to produce large-scale pure copper, bronze, brass and white copper. Among them, the mold, which plays an important role in product quality, is made of isostatic pressure graphite material. Due to its excellent performance in heat conduction, heat stability, self lubrication, anti wetting and chemical inertness, the isostatic pressure graphite material has become an irreplaceable material for making mold.

IV. other uses

Isostatic pressure graphite is also used to make sintering mould of diamond tool and hard alloy, heat field components of optical fiber drawing machine (heater, heat preservation cylinder, etc.), heat field components of vacuum heat treatment furnace (heater, bearing frame, etc.), precision graphite heat exchanger, mechanical seal components, piston ring, bearing, rocket nozzle, etc., which also play an important role in nuclear industry.