Processing technology of siliconized graphite product

Abstract

The invention discloses a processing technology of a siliconized graphite product. The processing technology of the graphite product comprises the following steps: 1) firstly obtaining a graphite blank having a smooth surface by coarsely processing and fine processing a graphite blank matrix; reserving a processing allowance of 0.05-0.5mm; 2) implementing a graphite siliconization process to the graphite blank by a vacuum gas phase deposition reaction method; forming a siliconized graphite coarse product having a silicon carbide layer on the surface thereof; 3) soaking the siliconized graphite coarse product obtained by the step 2) into a melting sodium hydroxide for removing the free silicon therein; and 4) finally obtaining a required siliconized graphite product by rinsing, drying and machining sequentially. The processing technology of the graphite product employs the gas phase deposition reaction method to implement the silicon carbonization process to the fine processed graphite surface. The surface of the graphite blank is smooth and beneficial to a uniform permeation of the silicon; in the subsequent machining, the damage to the silicon carbide layer formed on the surface is small; the reserved machining allowance is small, thus the subsequent machining is easy, the precision of the siliconized graphite product is easy to control, and the rate of the finished products is higher than 98%.

Description

technical field [0001] The invention relates to a processing technology of silicified graphite products, belonging to the technical field of composite materials and processing thereof. Background technique [0002] Silicified graphite is also called silicon carbide coated graphite or silicon infiltrated graphite. It is a new type of silicon carbide / graphite composite material composed of silicon carbide, graphite, and free silicon, which is formed by infiltrating silicon or silicon carbide on the surface or deep layer of graphite as the matrix. Siliconized graphite combines the characteristics of carbon and silicon carbide. It not only has the self-lubricating properties of carbon graphite materials, good electrical and thermal conductivity and thermal shock resistance, but also has the advantages of high hardness, oxidation resistance and chemical corrosion resistance of silicon carbide. Therefore, silicified graphite materials are used more and more widely, and are espe...

AI Technical Summary

Problems solved by technology

[0003] At present, silicified graphite is formed by chemical vapor deposition, chemical vapor reaction and liquid silicon infiltration reaction to form a silicon carbide layer on the surface of rough graphite blanks. The processing allowance of graphite blanks is 0.1 ~ 1mm, and the surface roughness is greater than Ra12. .5, the surface roughness after processing is generally greater than Ra3.2. When the blank with large surface roughness is used for silicon carbide treatment to prepare silicified graphite, there are post-machining damage to the surface silicon carbide layer, great processing difficulty, and product size. The accuracy is difficult to control, the yield rate is low (about 80%) and other shortcomings