CN109202068B

CN109202068B - Corrosion-resistant supporting plate

Info

Publication number: CN109202068B
Application number: CN201811010777.0A
Authority: CN
Inventors: 华吉; 华胜
Original assignee: Ningbo Huayuan Jingte Metal Products Co ltd
Current assignee: Ningbo Huayuan Jingte Metal Products Co ltd
Priority date: 2018-08-31
Filing date: 2018-08-31
Publication date: 2021-02-05
Anticipated expiration: 2038-08-31
Also published as: CN109202068A

Abstract

The invention relates to a corrosion-resistant support plate, which belongs to the field of metal materials and comprises the following materials in percentage by mass: alumina powder: 11-13%, Si powder: 1-3%, carbon black: 0.1-5%, Se powder: 0.1-0.5%, Lu powder: 0.02-0.06% and the balance corundum. The specific addition of the composite carbon black with higher content can ensure that most of carbon elements are combined with oxygen and dissipated in the smelting process, so that the carbon content in the aluminum alloy is controlled not to be too high, the embrittlement caused by too high carbon content is avoided, the alloy is prepared by the processes of pretreatment, material mixing, molding and the like, and the surface strength, the hardness and the corrosion resistance of the alloy are improved.

Description

Corrosion-resistant supporting plate

Technical Field

The invention relates to a corrosion-resistant support plate, and belongs to the field of metal materials.

Background

In daily life or industrial production, different types of devices are often needed, so that a supporting plate is needed for supporting, and a part of devices need to be stably operated for a long time, so that a better supporting effect of the supporting plate is needed.

The properties of the support plate thus largely determine the stability of the different devices. At present, in common backup pad, adopt the steel backup pad to support, but steel itself receives the corruption easily, and the life-span is shorter, so will electroplate the protection to the steel backup pad surface, and electroplate and can cause environmental pollution, must not repay, we have adopted aluminum alloy material preparation backup pad, have stronger resistance again when guaranteeing intensity.

The aluminum alloy is an alloy system which is formed by adding a certain amount of manganese, silicon and other additive elements and controlling the content of impurity elements on the basis of aluminum. The aluminum alloy has the advantages of high strength, high hardness and light weight, and is suitable for being used as a structural material. Except that the performance of the aluminum alloy is affected by the added elements of the aluminum alloy, the processing technology of the aluminum alloy is also affected, and the traditional alloy adopts the processes of die-casting molding, machining turning and the like, so that the defect that the tolerance precision of a die-casting piece is difficult to meet the technical requirement and the size of a product needs to be ensured by machining.

Aiming at the defects of low hardness, non-wear resistance and the like of the traditional alloy, the patent publication No. 103667832A discloses an aluminum alloy pipe, which improves the mechanical properties and the like of products. However, the material and process of the aluminum alloy of the patent are conventional, and the improvement of the alloy performance is limited.

Disclosure of Invention

In view of the above problems, the present invention provides a high-strength, high-hardness, corrosion-resistant support plate.

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

the corrosion-resistant support plate is composed of the following materials in percentage by mass: alumina powder: 11-13%, Si powder: 1-3%, carbon black: 0.1-5%, Se powder: 0.1-0.5%, Lu powder: 0.02-0.06% and the balance corundum.

The invention is simpler in selection of the aluminum alloy raw material, and the content of the aluminum alloy raw material is strictly controlled, so that the performance of the alloy can be better exerted. Firstly, the aluminum alloy raw material of the invention is not only prepared by adopting metal or nonmetal simple substances, but also selects metal oxide and corundum, the metal oxide and the corundum are simple and easy to obtain, the production cost can be greatly reduced, and simultaneously, the content of aluminum oxide can be larger (because the precipitated aluminum can also be used as the main material of the alloy in the subsequent preparation process). At the moment, in order to smoothly remove oxygen elements by matching with metal oxides with larger content, the carbon black with higher content is specifically added, most of carbon elements can be combined with oxygen to escape in the subsequent smelting process, so that the carbon content in the aluminum alloy is controlled not to be too high (actually kept in the range of low carbon aluminum), and the situation that the aluminum alloy becomes brittle due to too high carbon content is avoided. The selenium powder has strong oxygen absorption property, and can combine partial oxygen to form a eutectic body and enlarge the number of phases formed in the metallurgical process, which is reflected in the expression of the alloy as high strength. The rare earth element Lu with larger relative molecular mass is adopted instead of Ce, and the sedimentation strengthening effect is mainly utilized, so that the alloy has better hardness and does not lose toughness.

Preferably, the carbon black comprises one or more of carbon blacks with the particle size of 40-60nm, 120-400nm and 500-800 nm.

More preferably, the carbon black is composite carbon black, and is composed of the carbon blacks with different particle diameters according to the ratio of 1:1: 1.

The carbon black with smaller particle size is beneficial to the densification of alloy materials and the absorption effect of the carbon black on thermal stress, reduces the damage of thermal shock on material structures, and is beneficial to the formation of silicon carbide whiskers with larger length-diameter ratio on the alloy materials at high temperature, so that the mechanical property of the alloy is improved.

Preferably, the particle size of the alumina powder is 0.01 to 3 μm. The granularity of the alumina powder is controlled in a smaller range, the surface activity of the alumina powder can be increased, the alumina powder becomes activated alumina powder, and the alumina powder is easier to combine with other materials during mixing and is easier to react after being heated.

Preferably, the corundum is processed into a plurality of particle sizes, wherein the particle size of the corundum is 3-6mm and accounts for 28-32% of the total corundum amount, the particle size of the corundum is 0.5-1.5mm and accounts for 20-24% of the total corundum amount, the particle size of the corundum is 100-400 microns and accounts for 14-18% of the total corundum amount, and the balance is the corundum with the particle size of less than 0.1 mm. The corundum serving as a main material of the alloy has a large influence on subsequent preparation, corundum particles with different particle sizes are crushed, a layering feeling is generated after mixing, the space among different powders can be utilized to the maximum extent, a tighter whole is formed, the structural gap after forming is reduced, and the strength of the product is improved.

The invention also provides another technical scheme while reasonably selecting the material proportion:

a preparation method of a corrosion-resistant support plate comprises the following steps:

(1) pretreatment: weighing the materials, mixing the carbon black and the alumina powder in a ball mill, adding absolute ethyl alcohol for dispersion, and performing ball milling, drying and grinding to obtain mixed powder 1;

(2) mixing materials: premixing Si powder, Se powder and Lu powder for 12-14min to obtain mixed powder 2, crushing corundum into powder with different particle sizes, mixing, slowly adding an adhesive, mixing for 3-5min to obtain mixed powder 3, uniformly mixing the mixed powder 1, the mixed powder 2 and the mixed powder 3, and performing pre-pressing treatment to obtain a support plate blank;

(3) molding: firstly, curing the support plate blank, then uniformly wrapping the support plate blank with common carbon powder, and sintering and forming in an inert atmosphere to obtain a support plate finished product.

The invention can mix the different raw materials step by step to achieve the full mixing of the powder materials to the utmost extent, the deep mixing process can promote the different strengthening phases formed in the firing process, and the superposition degree between the phases is higher, namely the compactness of the alloy structure is enhanced, and the higher strength is highlighted. As for wrapping with carbon powder before forming, the method can isolate possible damage to the alloy caused by trace oxidizing gas, further increase the carbon content on the surface of the alloy, is equivalent to carburizing treatment, and improves the surface strength, hardness and corrosion resistance of the alloy.

Preferably, the adhesive in step (2) comprises one or two of liquid epoxy resin and liquid phenolic resin. The resin with relatively small molecular mass is adopted and can be in a liquid state at normal temperature, which is beneficial to reducing gaps among corundum with different particle sizes, discharging air in the gaps and simultaneously strengthening the connection among corundum and corundum.

Preferably, the blending time in the step (2) is 14-16h, and the pressure obtained by pre-pressing treatment is 170-200 MPa. The blending time is longer than the mixing time, and the blending time is long, so that certain heat and friction are generated, the pre-combination reaction between different powders is promoted, and the partially pre-combined substances form a strengthening phase during firing.

Preferably, the curing treatment in the step (3) is carried out at the temperature of 180-200 ℃ for 16-20 h. The curing treatment is essentially a heat treatment that eliminates in advance the residual stresses that form after mixing and pre-pressing.

Preferably, the sintering treatment in the step (3) is specifically: respectively preserving the heat for 1-2h at 740-760 ℃, 880-920 ℃ and 1250-1350 ℃. Three times of sintering at different temperatures, and the temperature is higher than that of one time, so that the gaps of the product during powder metallurgy forming can be greatly reduced, and the defect that the product is easy to damage during use is avoided.

Compared with the prior art, the invention has the following advantages:

(1) the invention selects the metal oxide and the corundum which are simple and easy to obtain, and can greatly reduce the production cost.

(2) According to the invention, the carbon black with higher content is added specifically, so that most of carbon elements can be combined with oxygen to escape in the subsequent smelting process, the carbon content in the aluminum alloy is controlled not to be too high, and the situation that the aluminum alloy becomes brittle due to too high carbon content is avoided.

(3) The carbon powder is wrapped before forming, so that the alloy can be isolated from possible damage caused by trace oxidizing gas, the surface carbon content of the alloy can be further increased, the carburization treatment is equivalent, and the surface strength, hardness and corrosion resistance of the alloy are improved.

Detailed Description

The following are specific examples of the present invention and further describe the technical solutions of the present invention, but the present invention is not limited to these examples.

Example 1

Preparing materials: weighing the raw materials in percentage by mass, wherein the weight ratio of alumina powder: 12%, Si powder: 2%, carbon black: 3% of Se powder: 0.3%, Lu powder: 0.04 percent and the balance of corundum, wherein the carbon black is composite carbon black with the grain diameters of 50nm, 300nm and 600nm, the granularity of alumina powder is 1.8 mu m, the corundum is processed into a plurality of granularities, the granularity of 5mm accounts for 30 percent of the total amount of the corundum, the granularity of 1mm accounts for 22 percent of the total amount of the corundum, the granularity of 270 microns accounts for 16 percent of the total amount of the corundum, and the balance is corundum with the granularity of less than 0.1 mm.

Pretreatment: firstly, mixing the composite carbon black and alumina powder, placing the mixture in a ball mill, adding absolute ethyl alcohol for dispersion, and carrying out ball milling, drying and grinding to obtain mixed powder 1;

mixing materials: premixing Si powder, Se powder and Lu powder for 13min to obtain mixed powder 2, mixing the corundum powder with different particle sizes, slowly adding epoxy resin, mixing for 4min to obtain mixed powder 3, uniformly blending the mixed powder 1, the mixed powder 2 and the mixed powder 3 for 15h, and performing pre-pressing treatment under 180MPa to obtain a support plate blank;

molding: curing the support plate blank at 190 ℃ for 18h, uniformly wrapping the support plate blank with common carbon powder, and respectively preserving heat at 750 ℃, 900 ℃ and 1300 ℃ for 1.5h in an inert atmosphere to obtain a support plate finished product.

Example 2

Preparing materials: weighing the raw materials in percentage by mass, wherein the weight ratio of alumina powder: 11%, Si powder: 1% of carbon black: 0.1%, Se powder: 0.1%, Lu powder: 0.02 percent and the balance of corundum, wherein the carbon black comprises composite carbon black with the grain diameter of 40nm and 120nm, the granularity of alumina powder is 0.01 mu m, the corundum is processed into a plurality of granularities, the granularity of 3mm accounts for 28 percent of the total corundum, the granularity of 0.5mm accounts for 20 percent of the total corundum, the granularity of 100 microns accounts for 14 percent of the total corundum, and the balance is corundum with the granularity of less than 0.1 mm.

Example 3

Preparing materials: weighing the raw materials in percentage by mass, wherein the weight ratio of alumina powder: 13%, Si powder: 3% of carbon black: 5% and Se powder: 0.5%, Lu powder: 0.06 percent and the balance of corundum, wherein the carbon black comprises composite carbon black with the grain diameter of 60nm and 800nm, the granularity of alumina powder is 3 mu m, the corundum is processed into a plurality of granularities, the 6mm granularity accounts for 32 percent of the total corundum amount, the 1.5mm granularity accounts for 24 percent of the total corundum amount, the 400 micron granularity accounts for 18 percent of the total corundum amount, and the balance is corundum with the granularity smaller than 0.1 mm.

Example 4

mixing materials: premixing Si powder, Se powder and Lu powder for 12min to obtain mixed powder 2, mixing the corundum powder with different particle sizes, slowly adding liquid phenolic resin, mixing for 3min to obtain mixed powder 3, uniformly blending the mixed powder 1, the mixed powder 2 and the mixed powder 3 for 14h, and pre-pressing at 170MPa to obtain a support plate blank;

Example 5

mixing materials: premixing Si powder, Se powder and Lu powder for 14min to obtain mixed powder 2, mixing the corundum powder with different particle sizes, slowly adding epoxy resin, mixing for 5min to obtain mixed powder 3, uniformly blending the mixed powder 1, the mixed powder 2 and the mixed powder 3 for 16h, and pre-pressing under 170-200MPa to obtain a support plate blank;

Example 6

molding: curing the support plate blank at 180 ℃ for 16h, uniformly wrapping the support plate blank with common carbon powder, and respectively preserving heat at 740 ℃, 880 ℃ and 1250 ℃ for 1h in an inert atmosphere to obtain a support plate finished product.

Example 7

molding: curing the support plate blank at 200 ℃ for 20h, uniformly wrapping the support plate blank with common carbon powder, and respectively preserving heat at 760 ℃, 920 ℃ and 1350 ℃ for 2h in an inert atmosphere to obtain a support plate finished product.

Example 8

The only difference from example 1 is that the particle diameter of the raw material carbon black of example 8 is 30 nm.

Example 9

The only difference from example 1 is that the particle diameter of the raw material carbon black of example 9 is 1 μm.

Example 10

The only difference from example 1 is that the raw material corundum of example 10 is crushed into powder having a particle size of 1mm only.

Example 11

The only difference from example 1 is that example 11 directly sinters and molds all the raw material mixed powders.

Comparative example 1

The only difference from example 1 is that the feedstock of comparative example 1 does not contain carbon black.

Comparative example 2

The only difference from example 1 is that comparative example 2 was molded without curing treatment.

Comparative example 3

The only difference from example 1 is that comparative example 3 was molded without carbon powder coating.

The products of examples 1 to 11 and comparative examples 1 to 3 were tested for strength, toughness, corrosion resistance and hardness, and the results are shown in Table 1:

table 1: properties of the products of examples 1 to 11 and comparative examples 1 to 3

The corrosion resistance data in the table is the time at which corrosion starts to appear on the surface of the product.

While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

Claims

1. The corrosion-resistant support plate is characterized by comprising the following materials in percentage by mass: alumina powder: 11-13%, Si powder: 1-3%, carbon black: 0.1-5%, Se powder: 0.1-0.5%, Lu powder: 0.02-0.06% and the balance corundum; the granularity of the alumina powder is 0.01-3 mu m;

the preparation method of the corrosion-resistant support plate comprises the following steps:

(1) pretreatment: weighing raw materials according to mass percentage, mixing carbon black and alumina powder, placing the mixture in a ball mill, adding absolute ethyl alcohol for dispersion, carrying out ball milling, drying and grinding to obtain mixed powder 1;

(3) molding: firstly, curing a support plate blank, uniformly wrapping common carbon powder on the support plate blank, and sintering and molding in an inert atmosphere to obtain a support plate finished product; the sintering treatment specifically comprises the following steps: respectively preserving the heat for 1-2h at 740-760 ℃, 880-920 ℃ and 1250-1350 ℃.

2. The support plate as set forth in claim 1, wherein the carbon black includes one or more of carbon black having a particle size of 40-60nm, 120-400nm, 500-800 nm.

3. The support plate as set forth in claim 1, wherein the corundum is processed into a plurality of grain sizes, the grain size of 3-6mm accounts for 28-32% of the total corundum amount, the grain size of 0.5-1.5mm accounts for 20-24% of the total corundum amount, the grain size of 100-400 μm accounts for 14-18% of the total corundum amount, and the balance is corundum with a grain size of less than 0.1 mm.

4. The support plate of claim 1, wherein the adhesive of step (2) comprises one or both of a liquid epoxy resin, a liquid phenolic resin.

5. The support plate as set forth in claim 1, wherein the blending time in step (2) is 14-16h, and the pressure of the pre-pressing treatment is 170-200 MPa.

6. The supporting plate as set forth in claim 1, wherein the curing treatment in step (3) is carried out at a temperature of 180 ℃ and 200 ℃ for a curing time of 16-20 h.