阅读说明：本技术 一种精密铸模用模料及其制备方法 (Mold material for precision casting mold and preparation method thereof ) 是由 陈涛 卢发昌 王信伟 于 2018-08-13 设计创作，主要内容包括：本发明属于精密铸造技术领域,特别涉及一种精密铸模用模料及其制备方法,将褐煤蜡、聚乙烯蜡、小烛树蜡、乙烯-醋酸乙烯共聚物、硬脂酸依次按步骤通话添加制得精密铸模用模料,强度高,不易变形；灰度低,减少对金属铸造的污染；易脱模,脱模时易随蜡模熔化流出型壳；在精密铸造过程中,能有效提高生产效率的特点。(The invention belongs to the technical field of precision casting, and particularly relates to a mold material for a precision casting mold and a preparation method thereof, wherein the mold material for the precision casting mold is prepared by sequentially adding lignite wax, polyethylene wax, candelilla wax, ethylene-vinyl acetate copolymer and stearic acid according to step communication, and has high strength and difficult deformation; the gray level is low, and the pollution to metal casting is reduced; the mold is easy to demould, and the wax mold is easy to melt and flow out of the shell during demoulding; in the precision casting process, the production efficiency can be effectively improved.)

1. The mold material for the precision casting mold is characterized by comprising the following raw materials in parts by mass: 44-46 parts of montan wax, 2.5-3.5 parts of polyethylene wax, 34-36 parts of candelilla wax, 3.5-4.5 parts of ethylene-vinyl acetate copolymer and 12-14 parts of stearic acid.

2. A method for producing a molding material for precision casting molds according to claim 1, comprising the steps of:

(1) dividing candelilla wax into two parts, heating one part at 120 deg.C, stirring continuously to melt, adding another part of candelilla wax, heating continuously, and stirring continuously to melt to obtain molten candelilla wax A;

(2) continuously heating the molten candelilla wax A obtained in the step (1) at 100-120 ℃, adding polyethylene wax, and continuously stirring until the molten candelilla wax A is completely molten to obtain a mixture B;

(3) continuously heating the mixture B obtained in the step (2) at 110-120 ℃, adding an ethylene-vinyl acetate copolymer, and continuously stirring until the mixture is completely molten to obtain a mixture C;

(4) continuously heating the mixture C obtained in the step (3) at 120 ℃, adding stearic acid, and continuously stirring until the mixture C is completely melted to obtain a mixture D;

(5) continuously heating the mixture D obtained in the step (4) at 110-120 ℃, and continuously stirring;

(6) reducing the temperature of the mixture D processed in the step (5) to 100 ℃, continuing heating and stirring, adding montan wax at the temperature of 90-100 ℃, and heating and stirring until the montan wax is molten to obtain a mixture E;

(7) and (4) continuously stirring and heating the mixture E obtained in the step (6), cooling to 80-90 ℃ and preparing into particles to obtain the die material for the precision casting die.

3. The method for producing a molding material for precision casting molds according to claim 2, wherein the heating time in each of the step (2), the step (3) and the step (4) is 1 to 2 minutes.

4. The method for producing a molding material for precision molds according to claim 2, wherein the heating time in step (5) and the heating time in step (7) are both 3 to 4 hours.

5. The method of producing a molding material for precision molds according to claim 2, wherein the heating time in the step (6) is 30 to 60 minutes.

Technical Field

The invention belongs to the technical field of precision casting, and particularly relates to a mold material for a precision casting mold and a preparation method thereof.

Background

With the development of society, precision castings have been widely used in the aviation, weapon, and other industrial sectors, particularly in electronics, petroleum, chemical, transportation, light industry, textile, pharmaceutical, medical, pump, and valve components.

The mould material commonly used at present is two or three of sodium dodecyl benzene sulfonate, stearic acid and polyethylene wax, and has good plasticity and filling property, but the mould material has poor thermal stability, low strength, high ash content, unfixed demoulding time, generates a large amount of waste products, has low quality and high cost, seriously influences the improvement of casting quality, has small competitiveness in the international market of the produced casting, and cannot meet the requirement of the precision casting industry.

However, many investment casting enterprises in China want to produce castings for export, and the quality of the castings is required to be improved for export. Therefore, advanced investment casting equipment and high quality mold material are required in the production process.

Disclosure of Invention

The invention aims to solve the problems and provides a mold material for a precision casting mold and a preparation method thereof, and the prepared mold material for the precision casting mold has good dimensional stability, high strength, low ash content and easy demolding.

The invention is realized by adopting the following technical scheme:

the mold material for the precision casting mold comprises the following raw materials in parts by mass: 44-46 parts of montan wax, 2.5-3.5 parts of polyethylene wax, 34-36 parts of candelilla wax, 3.5-4.5 parts of ethylene-vinyl acetate copolymer and 12-14 parts of stearic acid.

The invention also provides a method for preparing the mould material for the precision casting mould, which comprises the following steps:

(1) dividing candelilla wax into two parts, heating one part at 120 deg.C, stirring continuously to melt, adding another part of candelilla wax, heating continuously, and stirring continuously to melt to obtain molten candelilla wax A;

(2) continuously heating the molten candelilla wax A obtained in the step (1) at 100-120 ℃, adding polyethylene wax, and continuously stirring until the molten candelilla wax A is completely molten to obtain a mixture B;

(3) continuously heating the mixture B obtained in the step (2) at 110-120 ℃, adding an ethylene-vinyl acetate copolymer, and continuously stirring until the mixture is completely molten to obtain a mixture C;

(4) continuously heating the mixture C obtained in the step (3) at 120 ℃, adding stearic acid, and continuously stirring until the mixture C is completely melted to obtain a mixture D;

(5) continuously heating the mixture D obtained in the step (4) at 110-120 ℃, and continuously stirring;

(6) reducing the temperature of the mixture D processed in the step (5) to 100 ℃, continuing heating and stirring, adding montan wax at the temperature of 90-100 ℃, and heating and stirring until the montan wax is molten to obtain a mixture E;

(7) and (4) continuously stirring and heating the mixture E obtained in the step (6), cooling to 80-90 ℃ and preparing into particles to obtain the die material for the precision casting die.

Further, in the step (2), the step (3) and the step (4), the heating time is 1-2 minutes.

Further, the heating time in the step (5) and the heating time in the step (7) are both 3-4 hours.

Further, the heating time in the step (6) is 30-60 minutes.

The invention has the beneficial effects that:

1. the linear shrinkage rate and the sinking rate are low, so that the product has strong dimensional stability;

2. the penetration is within the range of 5-6 dmm, so that the product has high strength;

3. the gray level is low, so that the surface smoothness of the casting is good, the metal cannot be polluted, and the casting quality is high;

4. the softening point and the dropping point are in the ideal range, so that the die is easy to be removed in the casting process, and the production efficiency is higher.

Detailed Description

The technical solutions in the examples will be clearly and completely described below. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without any inventive step, are within the scope of the present invention.