| 摘要 |
FIELD: technological processes.SUBSTANCE: invention is intended for use in making articles operating in oxidative gas flows, in abrasive-containing gas and liquid flows, as well as friction pairs. Method of making thin-walled articles from composite material based on carbon-ceramic matrix with gradient thickness properties includes moulding a frame of layered or layered-stitched structure from heat-resistant carbon and/or silicon carbide fibres, sealing thereof with carbon-ceramic matrix material by saturating frame with polymer binder, moulding a plastic workpiece, high-temperature processing and saturation with pyrocarbon vacuum isothermal method to produce a workpiece, protective and supporting layers of which have different chemical activity with respect to silicon, and siliconisation of obtained workpiece. When moulding frame at boundary between protective and bearing layers, a film of impermeable elastic polymer material resistant to components of polymer binder is placed or formed, and if necessary stitching a package of fibrous workpieces using a stitching thread with elastic polymer coating. Protective and supporting layers in frame are soaked with ceramic-forming and coke-forming binder, respectively, saturation of carbonised and/or high-temperature treated plastic with pyrocarbon is carried out at 1,020-1,050 °C, pressure in reactor is 7-36 mm Hg, while feeding carbon-containing gas only on side of bearing layers to open porosity of material of said layers of 6-10 %. Before by siliconising workpiece open pores are filled with nanodispersed carbon or a mixture of nano- and fine carbon with particle size of not more than 5 mcm, siliconising is carried out via vapour-liquid-phase method at initial mass transfer of silicon into pores of material by capillary condensation of vapour thereof at workpiece temperature of 1,300-1,600 °C, pressure in reactor is not more than 27 mmHg, at temperature of silicon vapour higher than temperature of workpiece by 100-10 degrees.EFFECT: improved operational characteristics of thin-walled articles with gradient thickness properties.10 cl, 1 tbl, 19 ex |
