阅读说明：本技术 一种高温抗氧化石墨坩埚 (High-temperature oxidation-resistant graphite crucible ) 是由 王庆辉 于 2019-10-25 设计创作，主要内容包括：本发明涉及石墨坩埚技术领域,且公开了一种高温抗氧化石墨坩埚,包括以下重量份数配比的原料：100份的再生石墨粉、50～70份的白刚玉颗粒、15～25份的矾土孰料颗粒、5～10份的矾土孰料细粉、10～20份的α-Al-2O-3微粉、15～25份的Al-4SiC-4陶瓷、35～45份的酚醛树脂(PF)。本发明解决了目前石墨坩埚在有色金属的周期性熔炼过程中,其中的石墨炭素材料存在高温氧化的技术问题。(The invention relates to the technical field of graphite crucibles, and discloses a high-temperature oxidation-resistant graphite crucible which comprises the following raw materials in parts by weight: 100 parts of regenerated graphite powder, 50-70 parts of white corundum particles, 15-25 parts of alumina clinker particles, 5-10 parts of alumina clinker fine powder and 10-20 parts of alpha-Al 2 O 3 Micro powder and 15-25 parts of Al 4 SiC 4 Ceramic and 35-45 parts of phenolic resin (PF). The invention solves the technical problem that the graphite carbon material in the graphite crucible is oxidized at high temperature in the periodic smelting process of nonferrous metals.)

1. A high-temperature oxidation-resistant graphite crucible is characterized by comprisingThe following raw materials in parts by weight: 100 parts of regenerated graphite powder, 50-70 parts of white corundum particles, 15-25 parts of alumina clinker particles, 5-10 parts of alumina clinker fine powder and 10-20 parts of alpha-Al₂O₃Micro powder and 15-25 parts of Al₄SiC₄Ceramic and 35-45 parts of phenolic resin (PF).

2. The high-temperature oxidation-resistant graphite crucible as claimed in claim 1, wherein the graphite crucible comprises the following raw materials in parts by weight: 100 parts of regenerated graphite powder, 60 parts of white corundum particles, 20 parts of alumina clinker particles, 10 parts of alumina clinker fine powder and 10 parts of alpha-Al₂O₃Micropowder, 20 parts of Al₄SiC₄Ceramic, 40 parts of phenolic resin (PF).

3. The high-temperature oxidation-resistant graphite crucible as claimed in claim 2, wherein the graphite crucible comprises the following raw materials in parts by weight: average particle diameter of 100 parts<150um regenerated graphite powder, 60 parts of average grain diameter<250um white corundum particles, 20 parts of alumina clinker particles with average particle size of 160-250 um and 10 parts of alumina clinker particles with average particle size<Fine 38um bauxite clinker powder, 10 parts of which have an average particle size<38um alpha-Al₂O₃Fine powder, 20 parts of average particle diameter<25um Al₄SiC₄Ceramic, 40 parts of phenolic resin (PF).

4. The high-temperature oxidation-resistant graphite crucible as set forth in claim 3, wherein the preparation method of the graphite crucible comprises the steps of:

the method comprises the following steps: adding white corundum particles and alumina clinker particles into a liquid bonding agent consisting of phenolic resin (PF) and absolute ethyl alcohol, mixing to wet the white corundum particles and the alumina clinker particles, and uniformly attaching the liquid resin to the particles to obtain a first mixing component;

step two: adding the regenerated graphite powder into the mixing component I in the step I, and continuously mixing to ensure that the regenerated graphite powder is completely wetted and well bonded with a bonding agent to obtain a mixing component II;

step three: mixing fine powder of alumina clinker and alpha-Al₂O₃Fine powder of Al₄SiC₄Adding the ceramic into the second mixing component in the second step, continuously mixing to make pug uniform, and then placing to make absolute ethyl alcohol fully volatilize to obtain a third mixing component;

step four: pressing the mixing component III in the step III into a crucible blank by using a mould, wherein the forming pressure is 30 MPa;

then, drying the crucible blank at the temperature of 100 ℃, and then carrying out curing reaction on the crucible blank at the temperature of 200 ℃, wherein the curing and heat preservation time is 6 hours;

step five: and D, firing the crucible blank formed by curing in the step four in a reducing atmosphere by adopting a carbon-buried firing process, wherein the firing temperature is 1450 ℃, the firing heat preservation time is 5 hours, and then naturally cooling to room temperature to prepare the high-temperature oxidation-resistant graphite crucible.

Technical Field

The invention relates to the technical field of graphite crucibles, in particular to a high-temperature oxidation-resistant graphite crucible.

Background

Graphite is increasingly used in refractory products due to its excellent properties such as good chemical stability, high thermal conductivity, and low coefficient of thermal expansion. The graphite crucible is a typical example of a carbon composite refractory material, can be successfully used in a periodic smelting process of nonferrous metals at 800-1300 ℃, and is one of indispensable tools in the modern nonferrous metallurgy industry.

However, the graphite carbon material starts to be oxidized in an oxidizing atmosphere at a temperature of more than 400 ℃, the oxidation speed of more than 800 ℃ is accelerated, the graphite carbon material is easy to burn and lose due to chemical reaction with oxidizing gas, the carbon-containing refractory material is loose in organization structure due to decarbonization, the slag erosion resistance and the thermal shock resistance are greatly reduced, and even the strength is lost due to loose structure, so that the refractory material is damaged. Thus, high temperature oxidation of graphite crucibles is an important issue limiting their use.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a high-temperature oxidation-resistant graphite crucible, which aims to solve the technical problem that the graphite carbon material in the graphite crucible is oxidized at high temperature in the periodic smelting process of nonferrous metals.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme:

a high-temperature oxidation-resistant graphite crucible comprises the following raw materials in parts by weight: 100 parts of regenerated graphite powder, 50-70 parts of white corundum particles, 15-25 parts of alumina clinker particles, 5-10 parts of alumina clinker fine powder and 10-20 parts of alpha-Al₂O₃Micro powder and 15-25 parts of Al₄SiC₄Ceramic and 35-45 parts of phenolic resin (PF).

Further, the graphite crucible comprises the following raw materials in parts by weight: 100 parts of regenerated graphite powder, 60 parts of white corundum particles, 20 parts of alumina clinker particles, 10 parts of alumina clinker fine powder and 10 parts of alpha-Al₂O₃Micropowder, 20 parts of Al₄SiC₄Ceramic, 40 parts of phenolic resin (PF).

Further, the graphite crucible comprises the following raw materials in parts by weight: average particle diameter of 100 parts<150um regenerated graphite powder, 60 parts of average grain diameter<250um white corundum particles, 20 parts of alumina clinker particles with average particle size of 160-250 um and 10 parts of alumina clinker particles with average particle size<Fine 38um bauxite clinker powder, 10 parts of which have an average particle size<38um alpha-Al₂O₃Fine powder, 20 parts of average particle diameter<25um Al₄SiC₄Ceramic, 40 parts of phenolic resin (PF).

Further, the preparation method of the graphite crucible comprises the following steps:

the method comprises the following steps: adding white corundum particles and alumina clinker particles into a liquid bonding agent consisting of phenolic resin (PF) and absolute ethyl alcohol, mixing to wet the white corundum particles and the alumina clinker particles, and uniformly attaching the liquid resin to the particles to obtain a first mixing component;

step two: adding the regenerated graphite powder into the mixing component I in the step I, and continuously mixing to ensure that the regenerated graphite powder is completely wetted and well bonded with a bonding agent to obtain a mixing component II;

step three: mixing fine powder of alumina clinker and alpha-Al₂O₃Fine powder of Al₄SiC₄Adding the ceramic into the second mixing component in the second step, continuously mixing to make pug uniform, and then placing to make absolute ethyl alcohol fully volatilize to obtain a third mixing component;

step four: pressing the mixing component III in the step III into a crucible blank by using a mould, wherein the forming pressure is 30MPa, and the specification of a formed sample is 10 multiplied by 12 multiplied by 40 mm;

then, drying the crucible blank at the temperature of 100 ℃ for 1h, and then carrying out curing reaction on the crucible blank at the temperature of 200 ℃ for 6 h;

step five: and D, firing the crucible blank formed by curing in the step four in a reducing atmosphere by adopting a carbon-buried firing process, wherein the firing temperature is 1450 ℃, the firing heat preservation time is 5 hours, and then naturally cooling to room temperature to prepare the high-temperature oxidation-resistant graphite crucible.

(III) advantageous technical effects

Compared with the prior art, the invention has the following beneficial technical effects:

the invention is to oxidize Al at high temperature₄SiC₄Dispersing the ceramic into a graphite crucible which takes regenerated graphite powder as raw material, and in a high-temperature oxidizing atmosphere, dispersing non-oxide Al on the surface of the graphite crucible₄SiC₄The ceramic particles are oxidized to form Al oxide at 1300 deg.C₂O₃Film, formation of Al oxide at 1600 deg.C₂O₃And aluminosilicate SiO₂-Al₂O₃A thin film covering the surface of the graphite crucible and non-oxide Al₄SiC₄The volume expansion generated when the ceramic particles are oxidized can fill and seal the gas channel in the material, and the graphite crucible material is effectively protected by the isolation of the film and the sealing of the gas channel, so that the graphite crucible realizes the technical effect of self-healing and oxidation resistance;

the mass loss rate of the high-temperature oxidation-resistant graphite crucible prepared by the invention at 1300 ℃ for 1h is 21.64-23.25%, and the mass loss rate at 1600 ℃ for 1h is 25.61-28.79%, and compared with the mass loss rate of the high-temperature oxidation-resistant graphite crucible prepared by the comparative example at 1300 ℃ for 1h of 37.78% and the mass loss rate at 1600 ℃ for 1h of 41.09%, the technical effect of obviously improving the oxidation resistance of the graphite crucible at high temperature is achieved;

therefore, the technical problem that the graphite carbon material in the graphite crucible is oxidized at high temperature in the periodic smelting process of nonferrous metals at present is solved.

Detailed Description

The following raw materials used in the following examples and comparative examples are as follows:

crushing waste materials generated in the production process of graphite products, namely regenerated graphite, by a crusher, and then screening to obtain regenerated graphite powder with the average particle size of less than 150 um;

white corundum grains, average grain size<250um，Al₂O₃≥98％；

Alumina clinker particles with average particle size of 160-250 um and Al₂O₃>88％；

Fine powder of alumina clinker having an average particle diameter<38um，Al₂O₃>88％；

α-Al₂O₃Fine powder of average particle diameter<38um，Al₂O₃>98％；

Al₄SiC₄Ceramics, average particle size<25um, purity 99%;

the solid content of the phenolic resin (PF) is more than or equal to 75 percent, the carbon residue rate is more than or equal to 45 percent, the free aldehyde is less than 7 percent, and the heat treatment temperature is 200 ℃.

The first embodiment is as follows:

the high-temperature oxidation-resistant graphite crucible comprises the following raw materials in parts by weight: average particle diameter of 100g<150um regenerated graphite powder, 60g average particle diameter<White corundum particles of 250um, 20g of alumina clinker particles with average particle size of 160-250 um and 10g of alumina clinker particles with average particle size<Fine 38um bauxite clinker powder, 10g of average particle size<38um alpha-Al₂O₃Fine powder, average particle diameter of 20g<25um Al₄SiC₄Ceramic, 40g of phenolic resin (PF);

the preparation method of the high-temperature oxidation-resistant graphite crucible comprises the following steps:

the method comprises the following steps: adding 60g of white corundum particles with the average particle size of less than 250um and 20g of alumina clinker particles with the average particle size of 160-250 um into a liquid bonding agent consisting of 40g of phenolic resin (PF) and 30g of absolute ethyl alcohol, mixing to wet all the white corundum particles and the alumina clinker particles, and uniformly attaching the liquid resin to the particles to obtain a first mixing component;

step two: adding 100g of regenerated graphite powder with the average particle size of less than 150um into the mixing component I in the step I, and continuously mixing to ensure that the regenerated graphite powder is completely wetted and well bonded with a bonding agent to obtain a mixing component II;

step three: average particle diameter of 10g<Fine 38um bauxite clinker powder, 10g of average particle size<38um alpha-Al₂O₃Fine powder, average particle diameter of 20g<25um Al₄SiC₄Adding the ceramic into the second mixing component in the second step, continuously mixing to make pug uniform, and then placing to make absolute ethyl alcohol fully volatilize to obtain a third mixing component;

step four: pressing the mixing component III in the step III into a crucible blank by using a mould, wherein the forming pressure is 30MPa, and the specification of a formed sample is 10 multiplied by 12 multiplied by 40 mm;

then, drying the crucible blank at the temperature of 100 ℃ for 1h, and then carrying out curing reaction on the crucible blank at the temperature of 200 ℃ for 6 h;

step five: and D, firing the crucible blank formed by curing in the step four in a reducing atmosphere by adopting a carbon-buried firing process, wherein the firing temperature is 1450 ℃, the firing heat preservation time is 5 hours, and then naturally cooling to room temperature to prepare the high-temperature oxidation-resistant graphite crucible.

Example two:

the high-temperature oxidation-resistant graphite crucible comprises the following raw materials in parts by weight: average particle diameter of 100g<150um regenerated graphite powder, 50g average particle diameter<250um white corundum particles, 25g white corundum particles having an average particle diameter of 160-250 umAlumina clinker particles, 10g average particle size<Fine 38um bauxite clinker and 15g of average particle size<38um alpha-Al₂O₃Fine powder, average particle diameter of 15g<25um Al₄SiC₄Ceramic, 45g of phenolic resin (PF);

the preparation method of the high-temperature oxidation-resistant graphite crucible comprises the following steps:

the method comprises the following steps: adding 50g of white corundum particles with the average particle size of less than 250um and 25g of alumina clinker particles with the average particle size of 160-250 um into a liquid bonding agent consisting of 45g of phenolic resin (PF) and 35g of absolute ethyl alcohol, mixing to wet all the white corundum particles and the alumina clinker particles, and uniformly attaching the liquid resin to the particles to obtain a first mixing component;

step two: adding 100g of regenerated graphite powder with the average particle size of less than 150um into the mixing component I in the step I, and continuously mixing to ensure that the regenerated graphite powder is completely wetted and well bonded with a bonding agent to obtain a mixing component II;

step three: average particle diameter of 10g<Fine 38um bauxite clinker and 15g of average particle size<38um alpha-Al₂O₃Fine powder, average particle diameter of 15g<25um Al₄SiC₄Adding the ceramic into the second mixing component in the second step, continuously mixing to make pug uniform, and then placing to make absolute ethyl alcohol fully volatilize to obtain a third mixing component;

step four: pressing the mixing component III in the step III into a crucible blank by using a mould, wherein the forming pressure is 30MPa, and the specification of a formed sample is 10 multiplied by 12 multiplied by 40 mm;

then, drying the crucible blank at the temperature of 100 ℃ for 1h, and then carrying out curing reaction on the crucible blank at the temperature of 200 ℃ for 6 h;

step five: and D, firing the crucible blank formed by curing in the step four in a reducing atmosphere by adopting a carbon-buried firing process, wherein the firing temperature is 1450 ℃, the firing heat preservation time is 5 hours, and then naturally cooling to room temperature to prepare the high-temperature oxidation-resistant graphite crucible.

Example three:

high temperature oxidation resistant graphiteThe crucible comprises the following raw materials in parts by weight: average particle diameter of 100g<150um regenerated graphite powder, 70g average particle diameter<White corundum particles of 250um, 15g of alumina clinker particles with average particle size of 160-250 um and 5g of alumina clinker particles with average particle size<Fine 38um bauxite clinker powder, 20g of average particle size<38um alpha-Al₂O₃Fine powder, average particle diameter of 25g<25um Al₄SiC₄Ceramic, 35g of phenolic resin (PF);

the preparation method of the high-temperature oxidation-resistant graphite crucible comprises the following steps:

the method comprises the following steps: adding 70g of white corundum particles with the average particle size of less than 250um and 15g of alumina clinker particles with the average particle size of 160-250 um into a liquid bonding agent consisting of 35g of phenolic resin (PF) and 25g of absolute ethyl alcohol, mixing to wet all the white corundum particles and the alumina clinker particles, and uniformly attaching the liquid resin to the particles to obtain a first mixing component;

step two: adding 100g of regenerated graphite powder with the average particle size of less than 150um into the mixing component I in the step I, and continuously mixing to ensure that the regenerated graphite powder is completely wetted and well bonded with a bonding agent to obtain a mixing component II;

step three: average particle diameter of 5g<Fine 38um bauxite clinker powder, 20g of average particle size<38um alpha-Al₂O₃Fine powder, average particle diameter of 25g<25um Al₄SiC₄Adding the ceramic into the second mixing component in the second step, continuously mixing to make pug uniform, and then placing to make absolute ethyl alcohol fully volatilize to obtain a third mixing component;

step four: pressing the mixing component III in the step III into a crucible blank by using a mould, wherein the forming pressure is 30MPa, and the specification of a formed sample is 10 multiplied by 12 multiplied by 40 mm;

then, drying the crucible blank at the temperature of 100 ℃ for 1h, and then carrying out curing reaction on the crucible blank at the temperature of 200 ℃ for 6 h;

step five: and D, firing the crucible blank formed by curing in the step four in a reducing atmosphere by adopting a carbon-buried firing process, wherein the firing temperature is 1450 ℃, the firing heat preservation time is 5 hours, and then naturally cooling to room temperature to prepare the high-temperature oxidation-resistant graphite crucible.

Comparative example:

the high-temperature oxidation-resistant graphite crucible comprises the following raw materials in parts by weight: average particle diameter of 100g<150um regenerated graphite powder, 60g average particle diameter<White corundum particles of 250um, 20g of alumina clinker particles with average particle size of 160-250 um and 10g of alumina clinker particles with average particle size<Fine 38um bauxite clinker powder, 10g of average particle size<38um alpha-Al₂O₃Fine powder, 40g of phenol resin (PF);

the preparation method of the high-temperature oxidation-resistant graphite crucible comprises the following steps:

the method comprises the following steps: adding 60g of white corundum particles with the average particle size of less than 250um and 20g of alumina clinker particles with the average particle size of 160-250 um into a liquid bonding agent consisting of 40g of phenolic resin (PF) and 30g of absolute ethyl alcohol, mixing to wet all the white corundum particles and the alumina clinker particles, and uniformly attaching the liquid resin to the particles to obtain a first mixing component;

step two: adding 100g of regenerated graphite powder with the average particle size of less than 150um into the mixing component I in the step I, and continuously mixing to ensure that the regenerated graphite powder is completely wetted and well bonded with a bonding agent to obtain a mixing component II;

step three: average particle diameter of 10g<Fine 38um bauxite clinker powder, 10g of average particle size<38um alpha-Al₂O₃Micro powder is added into the second mixing component in the second step, mixing is continued to make pug uniform, and then the mixture is placed to make absolute ethyl alcohol fully volatilize to obtain a third mixing component;

step four: pressing the mixing component III in the step III into a crucible blank by using a mould, wherein the forming pressure is 30MPa, and the specification of a formed sample is 10 multiplied by 12 multiplied by 40 mm;

then, drying the crucible blank at the temperature of 100 ℃ for 1h, and then carrying out curing reaction on the crucible blank at the temperature of 200 ℃ for 6 h;

step five: and D, firing the crucible blank formed by curing in the step four in a reducing atmosphere by adopting a carbon-buried firing process, wherein the firing temperature is 1450 ℃, the firing heat preservation time is 5 hours, and then naturally cooling to room temperature to prepare the high-temperature oxidation-resistant graphite crucible.

And (3) performance testing:

the high-temperature oxidation-resistant graphite crucibles prepared in the above examples and comparative examples were tested for the mass loss rate, and the results are shown in table 1 below.

TABLE 1

Examples	1300 ℃ x 1h mass loss rate/%)	Mass loss rate at 1600 ℃ X1 h%
			Example one	21.64	25.61
Example two	23.25	27.58
			EXAMPLE III	22.84	28.79
Comparative example	37.78	41.09