Preparing process of silicon carbide whisker toughened zirconium diboride ceramic

Abstract

The invention belongs to the technical field of inorganic composite material preparation, and particularly relates to a preparing process of silicon carbide whisker toughened zirconium diboride ceramic. The preparing process comprises the steps: wrapping SiO2 on the surface of ZrB2 particles by a sol-gel process, drying, grinding, adding activated carbon, sufficiently mixing, heating the mixed material under the protection of flowing argon gas atmosphere, in-situ generating SiCw on the surface of ZrB2 by carbothermic reduction reaction between SiO2 and C to obtain ZrB2-SiCw powder, and then sintering to prepare the silicon carbide whisker toughened zirconium diboride ceramic material. According to the invention, the dispersion uniformity problem of SiCw in a substrate material is solved, the material structure is improved, the material performance is improved, the material preparation cost is lowered, the pollution caused by outside impurity elements is avoided, the application development of ZrB2-based extraordinarily-high-temperature composite material is positively promoted, and the preparing process has significant social benefits and economic benefits.

Description

technical field

[0001] The invention belongs to the technical field of preparation of inorganic composite materials, in particular to a preparation process of silicon carbide whisker toughened zirconium diboride ceramics. Background technique

[0002] With the rapid development of aerospace and national defense, modern aircraft (such as hypersonic aircraft, missiles, space shuttles, etc.) Requirements: Be able to adapt to some extreme environments such as supersonic cruise flight, atmospheric reentry, transatmospheric long-duration flight and rocket propulsion. Research on these ultra-high temperature materials is a key technical requirement for the development of aerospace and national defense. Therefore, the research on ultra-high temperature materials has very important strategic significance in the country's aerospace and national defense military.

[0003] ZrB 2 It has the advantages of high melting point (>3000°C), high strength, high hardness, good electrica...

Examples

Embodiment 1

[0031] Measure 29ml of tetraethyl orthosilicate, 46ml of absolute ethanol, and 4ml of distilled water, pour them into a large beaker, add dilute hydrochloric acid dropwise while stirring, adjust the pH value to 3-4, let stand for 17 hours to fully hydrolyze the tetraethyl orthosilicate , followed by the addition of 87.7 g ZrB 2 , vigorously stirred for 1 h, then added sodium hydroxide solution to adjust the pH to 8-9, and allowed to stand for 5-10 min to form a gel. Dry it in an oven at 80°C, dry it for 24 hours, and grind it into powder. Then take activated carbon 4.56g and carry out thorough mixing with above-mentioned powder body. Put the mixed powder obtained above into a graphite crucible and put it into a vacuum tube atmosphere furnace, raise the temperature to 1500°C at 10°C / min, keep it warm for 2.5h, and use flowing argon as a protective atmosphere to naturally cool to obtain ZrB 2 -SiC w Composite powder. figure 1 is ZrB 2 -SiC w The SEM photo of the composite ...

Embodiment 2

[0035] Measure 58ml of tetraethyl orthosilicate, 93ml of absolute ethanol, and 8ml of distilled water, pour them into a large beaker, add dilute hydrochloric acid dropwise while stirring, adjust the pH value to 3-4, let stand for 17 hours to fully hydrolyze the tetraethyl orthosilicate , followed by the addition of 77.95 g ZrB 2 , vigorously stirred for 1 h, then added sodium hydroxide solution to adjust the pH to 8-9, and allowed to stand for 5-10 min to form a gel. Dry it in an oven at 80°C, dry it for 24 hours, and grind it into powder. Then take 9.13g of activated carbon and fully mix with the above-mentioned powder. Put the mixed powder obtained above into a graphite crucible and put it into a vacuum tube atmosphere furnace, raise the temperature to 1500°C at 10°C / min, keep it warm for 2.5h, and use flowing argon as a protective atmosphere to naturally cool to obtain ZrB 2 -SiC w Composite powder.

[0036] Weigh 25g of the above-mentioned treated ZrB 2 -SiC w Put th...

Embodiment 3

[0039] Measure 93ml of tetraethyl orthosilicate, 148ml of absolute ethanol, and 13ml of distilled water, pour them into a large beaker, add dilute hydrochloric acid dropwise while stirring, adjust the pH value to 3-4, and let it stand for 17 hours to fully hydrolyze the tetraethyl orthosilicate , followed by the addition of 72.47 g ZrB 2 , vigorously stirred for 1 h, then added sodium hydroxide solution to adjust the pH to 8-9, and allowed to stand for 5-10 min to form a gel. Dry it in an oven at 80°C, dry it for 24 hours, and grind it into powder. Then take active carbon 14.55g and carry out thorough mixing with above-mentioned powder body. Put the mixed powder obtained above into a graphite crucible and put it into a vacuum tube atmosphere furnace, raise the temperature to 1500°C at 10°C / min, keep it warm for 2.5h, and use flowing argon as a protective atmosphere to naturally cool to obtain ZrB 2 -SiC w Composite powder.

[0040] Weigh 25g of the above-mentioned treated ...

technical field

[0001] The invention belongs to the technical field of preparation of inorganic composite materials, in particular to a preparation process of silicon carbide whisker toughened zirconium diboride ceramics. Background technique

[0002] With the rapid development of aerospace and national defense, modern aircraft (such as hypersonic aircraft, missiles, space shuttles, etc.) Requirements: Be able to adapt to some extreme environments such as supersonic cruise flight, atmospheric reentry, transatmospheric long-duration flight and rocket propulsion. Research on these ultra-high temperature materials is a key technical requirement for the development of aerospace and national defense. Therefore, the research on ultra-high temperature materials has very important strategic significance in the country's aerospace and national defense military.

[0003] ZrB 2 It has the advantages of high melting point (>3000°C), high strength, high hardness, good electrica...

Examples

Embodiment 1

[0031] Measure 29ml of tetraethyl orthosilicate, 46ml of absolute ethanol, and 4ml of distilled water, pour them into a large beaker, add dilute hydrochloric acid dropwise while stirring, adjust the pH value to 3-4, let stand for 17 hours to fully hydrolyze the tetraethyl orthosilicate , followed by the addition of 87.7 g ZrB 2 , vigorously stirred for 1 h, then added sodium hydroxide solution to adjust the pH to 8-9, and allowed to stand for 5-10 min to form a gel. Dry it in an oven at 80°C, dry it for 24 hours, and grind it into powder. Then take activated carbon 4.56g and carry out thorough mixing with above-mentioned powder body. Put the mixed powder obtained above into a graphite crucible and put it into a vacuum tube atmosphere furnace, raise the temperature to 1500°C at 10°C / min, keep it warm for 2.5h, and use flowing argon as a protective atmosphere to naturally cool to obtain ZrB 2 -SiC w Composite powder. figure 1 is ZrB 2 -SiC w The SEM photo of the composite ...

Embodiment 2

[0035] Measure 58ml of tetraethyl orthosilicate, 93ml of absolute ethanol, and 8ml of distilled water, pour them into a large beaker, add dilute hydrochloric acid dropwise while stirring, adjust the pH value to 3-4, let stand for 17 hours to fully hydrolyze the tetraethyl orthosilicate , followed by the addition of 77.95 g ZrB 2 , vigorously stirred for 1 h, then added sodium hydroxide solution to adjust the pH to 8-9, and allowed to stand for 5-10 min to form a gel. Dry it in an oven at 80°C, dry it for 24 hours, and grind it into powder. Then take 9.13g of activated carbon and fully mix with the above-mentioned powder. Put the mixed powder obtained above into a graphite crucible and put it into a vacuum tube atmosphere furnace, raise the temperature to 1500°C at 10°C / min, keep it warm for 2.5h, and use flowing argon as a protective atmosphere to naturally cool to obtain ZrB 2 -SiC w Composite powder.

[0036] Weigh 25g of the above-mentioned treated ZrB 2 -SiC w Put th...

Embodiment 3

[0039] Measure 93ml of tetraethyl orthosilicate, 148ml of absolute ethanol, and 13ml of distilled water, pour them into a large beaker, add dilute hydrochloric acid dropwise while stirring, adjust the pH value to 3-4, and let it stand for 17 hours to fully hydrolyze the tetraethyl orthosilicate , followed by the addition of 72.47 g ZrB 2 , vigorously stirred for 1 h, then added sodium hydroxide solution to adjust the pH to 8-9, and allowed to stand for 5-10 min to form a gel. Dry it in an oven at 80°C, dry it for 24 hours, and grind it into powder. Then take active carbon 14.55g and carry out thorough mixing with above-mentioned powder body. Put the mixed powder obtained above into a graphite crucible and put it into a vacuum tube atmosphere furnace, raise the temperature to 1500°C at 10°C / min, keep it warm for 2.5h, and use flowing argon as a protective atmosphere to naturally cool to obtain ZrB 2 -SiC w Composite powder.

[0040] Weigh 25g of the above-mentioned treated ...

Images