阅读说明：本技术 一种铸造用中温模料及其制备方法 (Medium-temperature die material for casting and preparation method thereof ) 是由 陈涛 卢发昌 王信伟 夏荣军 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,特别涉及一种铸造用中温模料及其制备方法,将褐煤蜡、聚乙烯蜡、巴西棕榈蜡、乙烯-醋酸乙烯共聚物、硬脂酸依次按步骤通话添加制得铸造用中温模料,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；具有较好的香味气氛；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 medium-temperature casting material for casting and a preparation method thereof, wherein the medium-temperature casting material for casting is prepared by sequentially adding montan wax, polyethylene wax, carnauba 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; has better fragrance atmosphere; in the precision casting process, the production efficiency can be effectively improved.)

1. The medium-temperature casting material 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 carnauba wax, 3.5-4.5 parts of ethylene-vinyl acetate copolymer and 12-14 parts of stearic acid.

2. A method for preparing a medium-temperature casting mold material according to claim 1, wherein the method comprises the following steps:

(1) dividing carnauba wax into two parts, heating one part at 120 ℃, continuously stirring until the carnauba wax is melted, adding the other part of carnauba wax, continuously heating, and continuously stirring until the carnauba wax is melted to obtain melted carnauba wax A;

(2) continuously heating the molten carnauba wax A obtained in the step (1) at 100-120 ℃, adding polyethylene wax, and continuously stirring until the mixture 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 medium-temperature casting material for casting.

3. A preparation method of a medium-temperature die material for casting according to claim 2, wherein in the step (2), the step (3) and the step (4), the heating time is 1-2 minutes.

4. A preparation method of a medium-temperature die material for casting according to claim 2, wherein the heating time in the step (5) and the heating time in the step (7) are both 3-4 hours.

5. A preparation method of medium-temperature casting mold material according to claim 2, characterized in that the heating time in the step (6) is 30-60 minutes.

Technical Field

The invention belongs to the technical field of precision casting, and particularly relates to a medium-temperature die material for casting 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 paraffin, 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 medium-temperature casting material for casting and a preparation method thereof.

The invention is realized by adopting the following technical scheme:

the medium-temperature casting material for casting 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 carnauba 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 medium-temperature casting material for casting, which comprises the following steps:

(1) dividing carnauba wax into two parts, heating one part at 120 ℃, continuously stirring until the carnauba wax is melted, adding the other part of carnauba wax, continuously heating, and continuously stirring until the carnauba wax is melted to obtain melted carnauba wax A;

(2) continuously heating the molten carnauba wax A obtained in the step (1) at 100-120 ℃, adding polyethylene wax, and continuously stirring until the mixture 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 medium-temperature casting material for casting.

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.