阅读说明：本技术 一种碳化硅预制件的烧结方法及铝碳化硅板的制备方法 (Sintering method of silicon carbide prefabricated part and preparation method of aluminum silicon carbide plate ) 是由 刘骏 蔡璐 刘波 王钢 汪国雄 张海波 于 2020-05-14 设计创作，主要内容包括：本发明公开了一种碳化硅预制件的烧结方法,包括如下步骤：步骤1：清洁工作设备,设备通电待机,步骤2：选出工作物料,整备后备用,步骤3：模具内表面基本处理,步骤4：物料检验及物料的基本操作,步骤5：热压烧结的后续处理,步骤6：对产品进行合格性判断及收集,本发明涉及铝碳化硅板技术领域。该碳化硅预制件的烧结方法及铝碳化硅板的制备方法,将不符合要求的物料剔除,提高了产品中的纯度,并且通过加入烧结辅助剂和在成型后的逐步升温,使得物料在高温下缓慢成型,内部结构逐渐得到加强,从而生产的碳化硅强度较高,适用范围较广,另外通过该在高压下进行烧结,进一步提高了碳化硅产品的强度和应用时的稳定性。(The invention discloses a sintering method of a silicon carbide prefabricated part, which comprises the following steps: step 1: cleaning the working equipment, powering on and waiting the equipment, and step 2: selecting the working materials, preparing for later use, and step 3: basically treating the inner surface of the mold, and step 4: material inspection and basic operation of the material, step 5: and (6) carrying out subsequent treatment of hot-pressing sintering, wherein the step: the invention relates to the technical field of aluminum silicon carbide plates, and discloses a method for judging and collecting the qualification of products. According to the sintering method of the silicon carbide prefabricated part and the preparation method of the aluminum silicon carbide plate, materials which do not meet requirements are removed, the purity of the product is improved, the materials are slowly formed at high temperature through adding a sintering auxiliary agent and gradually raising the temperature after forming, the internal structure is gradually strengthened, and therefore the produced silicon carbide is high in strength and wide in application range.)

1. A method of sintering a silicon carbide preform, comprising: the method comprises the following steps:

step 1: cleaning the working equipment, and powering on and standby the equipment: cleaning all equipment participating in sintering work by using purified water, wiping the equipment by using sterile cotton cloth, and electrifying the equipment to enter a standby state after obvious water drops do not exist on the surface;

step 2: selecting working materials, and preparing for later use: all materials needing to participate in the work are selected and placed in a working disc, and then all the materials are ground into powdery substances for later use through grinding equipment;

and step 3: basic treatment of the inner surface of the mold: before adding the material powder, a layer of boron nitride must be uniformly coated on the inner surface of the graphite mold;

and 4, step 4: material inspection and basic operation of materials: screening powdery materials, removing the materials which do not meet the requirements, adding the silicon carbide powder which meets the requirements into a mould, adding sintering aids such as magnesium oxide and the like, adding a proper amount of distilled water, kneading and molding, gradually heating to 2300-2500 ℃, and applying 300Kg/cm²The pressure of (2) is kept for 10-15 minutes;

and 5: and (3) carrying out subsequent treatment of hot-pressing sintering: after hot-pressing sintering is finished, pulling out the silicon carbide prefabricated part from the mold by adopting a demolding instrument;

step 6: judging and collecting the qualification of the product: all products are collected, the qualification rate of the products is detected through detection equipment, and the qualified products are preferentially stored.

2. A method of sintering a silicon carbide preform according to claim 1, wherein: the thickness of the boron nitride in the step 3 is 50 μm, and the particle size of the material powder is less than 20 μm.

3. A method of sintering a silicon carbide preform according to claim 1, wherein: in the step 1, the purified water can be replaced by distilled water, and the aseptic cotton cloth needs to be sterilized by ethylene oxide or ultraviolet rays.

4. A method of sintering a silicon carbide preform according to claim 1, wherein: in the step 4, the temperature rise speed is 100 ℃ per minute, and the added sintering auxiliary agent must be uniformly stirred with the silicon carbide powder.

5. A method of sintering a silicon carbide preform according to claim 1, wherein: in step 5, the mold must be cooled while pulling the silicon carbide out of the mold.

6. A preparation method of an aluminum silicon carbide plate is characterized by comprising the following steps: the method comprises the following steps:

step 1: basic operation of the silicon carbide preform: cleaning and disinfecting the silicon carbide prefabricated part, and then carrying out primary working treatment;

step 2: preparation of materials, preparatory operations: opening a hollow groove in the graphite model, and putting the silicon carbide prefabricated part into the hollow groove;

and step 3: infiltration and final forming: and (3) putting the whole into a vacuum furnace, gradually increasing the pressure, firstly adding aluminum liquid into the vacuum furnace, gradually pressurizing to 8MPa, keeping for 15 minutes, and finally obtaining a finished product.

7. The method of claim 6, wherein the step of preparing the aluminum silicon carbide plate comprises: in the step 2, the size of the empty groove is equal to the size of the outline of the silicon carbide product.

8. The method of claim 6, wherein the step of preparing the aluminum silicon carbide plate comprises: in the step 3, the pressurizing speed is 2MPa/min, and the finished product is used after being naturally cooled.

Technical Field

The invention relates to the technical field of aluminum silicon carbide plates, in particular to a sintering method of a silicon carbide prefabricated part and a preparation method of an aluminum silicon carbide plate.

Background

Silicon carbide has many other uses besides being used as an abrasive, for example, because of its chemical stability, high thermal conductivity, small thermal expansion coefficient and good wear resistance: the silicon carbide powder is coated on the inner wall of the water turbine impeller or the cylinder body by a special process, so that the wear resistance of the water turbine impeller or the cylinder body can be improved, and the service life of the water turbine impeller or the cylinder body can be prolonged; the high-grade refractory material has the advantages of thermal shock resistance, small volume, light weight, high strength and good energy-saving effect. The low-grade silicon carbide is an excellent deoxidizer, and can be used for accelerating the steel-making speed, conveniently controlling chemical components and improving the quality of steel. In addition, silicon carbide is also used in making great amount of silicon carbide rod for electric heating element, and aluminum silicon carbide is one kind of particle reinforced metal-base composite material with Al alloy as matrix and silicon carbide particle as reinforcement in certain form, proportion and distribution state based on the design requirement.

The common aluminum silicon carbide plate is manufactured by firstly manufacturing a silicon carbide prefabricated part and then manufacturing the aluminum silicon carbide plate through various manufacturing processes, but the common silicon carbide prefabricated part is usually manufactured by directly firing during manufacturing, and temperature and pressure rise treatment is lacked in the manufacturing process.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a sintering method of a silicon carbide prefabricated part and a preparation method of an aluminum silicon carbide plate, which solve the problems that the common aluminum silicon carbide plate needs to be manufactured in advance and then manufactured by various manufacturing processes, but the common silicon carbide prefabricated part is often directly fired and manufactured during manufacturing, temperature and pressure rise processing is lacked during manufacturing, and the aluminum silicon carbide plate manufactured by the method has short service life and low strength and is not beneficial to long-term safe use.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: a method of sintering a silicon carbide preform comprising the steps of:

step 1: cleaning the working equipment, and powering on and standby the equipment: cleaning all equipment participating in sintering work by using purified water, wiping the equipment by using sterile cotton cloth, and electrifying the equipment to enter a standby state after obvious water drops do not exist on the surface;

step 2: selecting working materials, and preparing for later use: all materials needing to participate in the work are selected and placed in a working disc, and then all the materials are ground into powdery substances for later use through grinding equipment;

and step 3: basic treatment of the inner surface of the mold: before adding the material powder, a layer of boron nitride must be uniformly coated on the inner surface of the graphite mold;

and 4, step 4: material inspection and basic operation of materials: screening powdery materials, removing the materials which do not meet the requirements, adding the silicon carbide powder which meets the requirements into a mould, adding sintering aids such as magnesium oxide and the like, adding a proper amount of distilled water, kneading and molding, gradually heating to 2300-2500 ℃, and applying 300Kg/cm²The pressure of (2) is kept for 10-15 minutes;

and 5: and (3) carrying out subsequent treatment of hot-pressing sintering: after hot-pressing sintering is finished, pulling out the silicon carbide prefabricated part from the mold by adopting a demolding instrument;

step 6: judging and collecting the qualification of the product: all products are collected, the qualification rate of the products is detected through detection equipment, and the qualified products are preferentially stored.

Preferably, the thickness of the boron nitride in the step 3 is 50 μm, and the particle size of the material powder is less than 20 μm.

Preferably, in the step 1, the purified water can be replaced by distilled water, and the sterilized cotton cloth needs to be sterilized by ethylene oxide or ultraviolet rays.

Preferably, in the step 4, the temperature rising speed is 100 degrees centigrade per minute, and the sintering aid added must be uniformly stirred with the silicon carbide powder.

Preferably, in step 5, the mold must be cooled while pulling the silicon carbide out of the mold.

The invention also discloses a preparation method of the aluminum silicon carbide plate, which comprises the following steps:

step 1: basic operation of the silicon carbide preform: cleaning and disinfecting the silicon carbide prefabricated part, and then carrying out primary working treatment;

step 2: preparation of materials, preparatory operations: opening a hollow groove in the graphite model, and putting the silicon carbide prefabricated part into the hollow groove;

and step 3: infiltration and final forming: putting the whole into a vacuum furnace, gradually increasing the pressure, firstly adding aluminum liquid into the vacuum furnace, gradually pressurizing to 8MPa, keeping for 15 minutes, and finally obtaining a finished product

Preferably, in the step 2, the size of the empty groove is equal to the size of the outer shape of the silicon carbide product.

Preferably, in the step 3, the pressurizing speed is 2MPa/min, and the finished product is used after being naturally cooled.

(III) advantageous effects

The invention provides a sintering method of a silicon carbide prefabricated part and a preparation method of an aluminum silicon carbide plate. Compared with the prior art, the method has the following beneficial effects:

(1) the sintering method of the silicon carbide prefabricated part and the preparation method of the aluminum silicon carbide plate comprise the following steps of 1: cleaning the working equipment, and powering on and standby the equipment: cleaning all the devices participating in sintering work by using purified water, wiping the devices clean by using sterile cotton cloth, electrifying the devices after the surfaces do not have obvious water drops, and entering a standby state, wherein the step 4: material inspection and basic operation of materials: screening powdery materials, removing the materials which do not meet the requirements, adding the silicon carbide powder which meets the requirements into a die, adding sintering aids such as magnesium oxide and the like, adding a proper amount of distilled water, kneading and molding, gradually heating to 2300 plus 2500 ℃, applying a pressure of 300Kg/cm2 to keep for 10-15 minutes, removing the materials which do not meet the requirements, improving the purity of the product, and gradually increasing the temperature after molding by adding the sintering aids to slowly mold the materials at high temperature, gradually strengthening the internal structure, so that the produced silicon carbide has higher strength and wider application range, and further improving the strength and the stability of the silicon carbide product when in use by sintering under high pressure.

(2) The sintering method of the silicon carbide prefabricated part and the preparation method of the aluminum silicon carbide plate comprise the following steps of 2: selecting working materials, and preparing for later use: all materials needing to participate in the work are selected and placed in a working disc, and then all the materials are ground into powdery substances for later use through grinding equipment; and step 3: basic treatment of the inner surface of the mold: before adding the material powder, a layer of boron nitride must be uniformly coated on the inner surface of the graphite mold, and under the condition of high-temperature and high-pressure sintering, the silicon nitride reacts with the graphite mold to generate silicon carbide on the surface, so that a layer of boron nitride is coated in the graphite mold to prevent the reaction and generate impurities, and the rapid demolding at the later stage is facilitated.

(3) The sintering method of the silicon carbide prefabricated part and the preparation method of the aluminum silicon carbide plate comprise the following steps of 5: and (3) carrying out subsequent treatment of hot-pressing sintering: after hot-pressing sintering is finished, pulling out the silicon carbide prefabricated part from the mold by adopting a demolding instrument; step 6: judging and collecting the qualification of the product: collect all products to through check out test set, detect the qualification rate in the product, will detect qualified product and preserve preferentially, because the initial stage of drawing of patterns is the high temperature high pressure condition, consequently when using this kind of drawing of patterns apparatus, can be fast accurate carry out drawing of patterns work, and the difference of the coefficient of expansion of model material and testpieces can produce stress when cooling at last, can assist operating personnel to draw of patterns fast.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the attached tables in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to table 1, the embodiment of the present invention provides three technical solutions: a sintering method of a silicon carbide prefabricated part specifically comprises the following embodiments: