CN103864450A

CN103864450A - Manufacture method for pressureless-sintered silicon carbide-based carbon fiber-added composite ceramic

Info

Publication number: CN103864450A
Application number: CN201210531914.1A
Authority: CN
Inventors: 孔令贵
Original assignee: XINDONGFANG TECHNOLOGY DEVELOPMENT Co Ltd (FENGFENG MINE)
Current assignee: XINDONGFANG TECHNOLOGY DEVELOPMENT Co Ltd (FENGFENG MINE)
Priority date: 2012-12-12
Filing date: 2012-12-12
Publication date: 2014-06-18
Anticipated expiration: 2032-12-12
Also published as: CN103864450B

Abstract

The invention relates to a novel ceramic manufacturing method, and in particular, relates to a manufacture method for a pressureless-sintered silicon carbide-based carbon fiber-added composite ceramic. The toughness, the flexural strength and the mechanical properties of the pressureless-sintered silicon carbide ceramic can be enhanced, and the manufacture method comprises the steps: 1) preparing ingredients, preparing 100 parts of a silicon carbide micro-powder, 5-10 parts of short carbon fiber, 0.5-1.5 parts of a dispersant, 1.5-2.5 parts of glycerol, and 0.4-1 part of boron carbide, and adding 70-100 parts of pure water; 2) carrying out ball milling, putting the ingredients of the step 1) into a ball mill, stirring for 3-5 hours, then adding 6-9 parts of a carbon black slurry, adding 3-5 parts of an aqueous solution containing 5-8% of PVC, again stirring by the ball mill, after stirring for 4-6 hours, adding a ceramic lubricant and a binder, and stirring for 10-15 hours in a stirring barrel; 3) carrying out spray granulation of the stirred material slurry of the step 2) by a spray granulator; and 4) carrying out dry-pressing molding of the granulation powder obtained after spray granulation with the pressure of 130-150 MPa by a steel mold or a cold isostatic pressing machine according to the size and the shape of the pressureless-sintered silicon carbide product.

Description

The silicon carbide-based carbon fiber composite ceramics manufacture method that adds of pressureless sintering

Technical field

The present invention relates to a kind of novel process for preparing ceramic, particularly relate to the silicon carbide-based carbon fiber composite ceramics manufacture method that adds of a kind of pressureless sintering.

Background technology

As everyone knows, pressureless sintering silicon carbide ceramic has that good in oxidation resistance, hardness are high, Heat stability is good, hot strength is large, thermal expansivity is little, thermal conductivity is large and anti-thermal shock and the premium properties such as resistance to chemical corrosion is good, be widely used in fields such as oil, chemical industry, machinery, space flight nuclear energy and military affairs, but the pressureless sintering silicon carbide ceramic of manufacturing under existing manufacture method because its fracture toughness property is poor, the little drawback such as frangible of impact resistance, be also subject to certain restriction in some application of special occasions.

Summary of the invention

For solving the problems of the technologies described above, the present invention can strengthen the toughness of pressureless sintering silicon carbide ceramic and bending strength with and mechanical property.

The silicon carbide-based carbon fiber composite ceramics manufacture method that adds of pressureless sintering of the present invention, comprises the following steps:

1), batching, prepare the silicon carbide micro-powder of 100 parts, the short carbon fiber of 5-10 part, the dispersion agent of 0.5-1.5 part, the norbide of 0.4-1 part add the pure water of 70-100 part; The glycerol of 15-2.5 part;

2), ball milling, by step 1) in batching put into ball mill and stir after 3-5 hour, add carbon black 6-9 part, add 5-8%PVC aqueous solution 3-5 part, and again stir by ball mill, stir and add lubricant and binding agent in agitation vat, to stir 10-15 hour after 4-6 hour;

3), with sponging granulator to step 2) in stir after batching carry out mist projection granulating,

4), the pelletizing after mist projection granulating is dry-pressing formed with the pressure of 130-150Ma by steel die or cold isostatic press according to the size and shape of required goods,

5), carry out roughing according to product requirement with lathe or milling machine,

6), do biscuiting degumming process with vacuum biscuiting electric furnace,

7), be filled with shielding gas after sintering to 1750-1850 DEG C with vacuum non-pressure sintering electric furnace and continue to sinter to 2220-2250 DEG C of end;

8), require to carry out ground finish according to product drawing.

Silicon carbide-based carbon fiber composite ceramics manufacture method, the described step 2 of adding of pressureless sintering of the present invention) in use ceramic lubricant be 2-3 part.

Silicon carbide-based carbon fiber composite ceramics manufacture method, the described step 2 of adding of pressureless sintering of the present invention) in use binding agent be 6-7 part.

Compared with prior art beneficial effect of the present invention is: adopt aforesaid method in pottery, to add short carbon fiber, make its in breaking-down process by fiber extract, the energy of the toughening mechanisms such as fiber-bridged, fracture deflection while consuming fracture, make material show as non-brittle fracture, thereby change the impact of its mechanical property and microtexture.The item such as bending strength and the toughness index of product is all greatly improved.

Embodiment

Below in conjunction with embodiment, the specific embodiment of the present invention is described in further detail.Following examples are used for illustrating the present invention, but are not used for limiting the scope of the invention.

As shown in Figure 1, the silicon carbide-based carbon fiber composite ceramics of pressureless sintering of the present invention manufacture method, comprises the following steps:

1), batching, prepare the silicon carbide micro-powder of 100 parts, the short carbon fiber of 5-10 part, the dispersion agent of 0.5-1.5 part, the norbide of 0.4-1 part add the pure water of 70-100 part; 1.5-2.5 the glycerol of part;

2), ball milling, by step 1) in batching put into ball mill and stir after 3-5 hour, add carbon black 6-9 part, add aqueous solution 3-5 part of 5-8%PVC, and again stir by ball mill, stir and add lubricant and binding agent in agitation vat, to stir 10-15 hour after 4-6 hour;

3), with sponging granulator to step 2) in stir after slip carry out mist projection granulating,

6), green compact are done to biscuiting degumming process with vacuum biscuiting electric furnace,

8), require to carry out ground finish according to product drawing.

The silicon carbide-based carbon fiber composite ceramics manufacture method that adds of pressureless sintering of the present invention, adopt aforesaid method in pottery, to add carbon fiber, make its in breaking-down process by fiber extract, the energy of the toughening mechanisms such as fiber-bridged, fracture deflection while consuming fracture, make material show as non-brittle fracture, thereby change the impact of its mechanical property and microtexture.The item such as bending strength and the toughness index of product is all greatly improved.

The above is only the preferred embodiment of the present invention; it should be pointed out that for those skilled in the art, do not departing under the prerequisite of the technology of the present invention principle; can also make some improvement and modification, these improve and modification also should be considered as protection scope of the present invention.

Claims

1. the silicon carbide-based carbon fiber composite ceramics manufacture method that adds of pressureless sintering, is characterized in that, comprises the following steps:

1), batching, prepare the silicon carbide micro-powder of 100 parts, the short carbon fiber of 5-10 part, the norbide of the dispersion agent of 0.5-1.5 part, the glycerol of 1.5-2.5 part, 0.4-1 part adds the pure water of 70-100 part;

2), ball milling, by step 1) in batching put into ball mill and stir after 3-5 hour, add carbon black 6-9 part, add 4 parts of the aqueous solution of 6%PVC, and again stir by ball mill, stir and add ceramic lubricant and binding agent in agitation vat, to stir 10-15 hour after 4-6 hour;

4), the pelletizing after mist projection granulating is dry-pressing formed with the pressure of 130-150Ma by steel die or cold isostatic press according to the size and shape of pressureless sintering silicon carbide articles,

6), do biscuiting degumming process with vacuum biscuiting electric furnace,

7), be filled with high purity protective gas after sintering to 1750-1850 DEG C with vacuum non-pressure sintering electric furnace and continue to sinter to 2220-2250 DEG C of end;

8), carry out ground finish according to product drawing dimensional requirement.

2. the silicon carbide-based carbon fiber composite ceramics manufacture method that adds of pressureless sintering as claimed in claim 1, is characterized in that described step 2) in use ceramic lubricant be 2-3 part.

3. the silicon carbide-based carbon fiber composite ceramics manufacture method that adds of pressureless sintering as claimed in claim 1, is characterized in that described step 2) in use binding agent be 6-7 part.