外文翻譯---碳結(jié)構(gòu)和固體顆粒侵蝕的保護(hù)高度多孔炭碳復(fù)合保溫材料的使用-材料科學(xué)-全文預(yù)覽
【正文】 類的多孔碳 (CC)復(fù)合材料與低密度范圍 — mg/m3， 運(yùn)用在真空和 惰性 保溫爐在高溫下 到 2800176。 唯一的例外是石墨箔材料顯示角度為最大侵蝕 角度為 60176。 此外 ,效果很薄的化學(xué)氣象沉積 (CVD)碳層上的油漆涂料和膠體石墨石墨鋁箔復(fù)合進(jìn)行了 檢驗(yàn)。 the porosity content of this fibre work is exceptionally high with 87% of the volume of the posite consisting of open and interconnected pores. The orientation of the fibres is evident in the micrograph in which the fibres lie preferentially in xy planes (. perpendicular to the z direction) but are random in direction within these planes. The thickness of the Calcoat colloidal graphite paint coating is variable, due to the brushing method of application, but generally is in the range 40— 60 lm (Fig. 2a). However, as a result of the high porosity content and the interconnected nature of the porosity in the CBCF substrate, some of the paint perates up to a depth of 600 lm (Fig. 2b). Calcoat M consists of Calcoat colloidal graphite paint, which contains submicrometre carbon particles, with the addition of coarser carbon particles and short fibres ((50 lm). The coarser carbon particles increase the viscosity of the paint which results in a thicker surface coating (80— 200 lm) by minimizing the extent of peration into the interior of the porous substrate (Fig. 2c). The CalcoatCVD is produced by depositing carbon from the gaseous phase on to the Calcoat coating in the CVD furnace. This process produces a layer of dense pyrolytic carbon about 5 lm thick on the surface of the paint coating with little peration (Fig. 2d). The FMI C3 C— C posite is produced from polyacrylonitrile (PAN) precursor carbon fibre cloth, which is about mm thick [21]. The cloth is impregnated with phenolic resin but it is evident that the resin does not adequately perate the fibre bundles (Fig. 3a). Large platelets of resinbased carbon (500 lm。 and 90176。5 mm. The erodent used was angular equiaxed silica sand obtained from Hepworth Minerals and Chemicals Ltd, Redhill, UK. The erodent was sieved to particle sizes between 150 and 300 lm, the mean size (by weight) was 230 lm which was found by a laser difrac tion method (Mastersizer 1005, Malvern Instruments Ltd, Malvern, UK). The velocity of the particles was 6 m s\1, found by the streaking camera technique at the position of the target. This method involved expo sing the film for a known length of time and measuring the length of the line that the particle produces on the film. Erosion tests were carried out at angles of 30176。 the xy plane is perpendicular to the direction of minimum thermal conductivity and hence is most likely to be the exposed surface of the insulation in a furnace. The coating and cladding materials exam ined in this paper were all carbon based and they are listed in Table I. The coating materials are defined as those that bond independently to the CBCF substrate,whereas the claddings are bonded by means of a car bonizing cement. Calcoat and Calcoat M are colloidal graphite paint coatings that were applied to the CBCF substrate by brushing. The material was subsequently heat treated at 900 176。 therefore, it is possible to reduce warping and cracking in the ponent . During gas quenching, parti culate m
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