阅读说明：本技术 一种球化丝及其制备方法 (Spheroidized filament and preparation method thereof ) 是由 李传军 李德厚 吕太昌 于 2021-10-10 设计创作，主要内容包括：本申请涉及稀土金属精深产品制备技术领域,具体公开了一种球化丝及其制备方法。球化丝包括镁25-29份、稀土元素1-3份、硅23-27份、钙3-5份、钡1-3份、锰粉20-34份、钨粉1-3份、铁13-23份；其制备方法为：熔炼、倒模、出模破碎、制粒、包粉。本申请的球化丝可用于炼钢或生产铸件,其具有提高由球化丝制得的铸件的硬度和冲击韧性,提升铸件质量的优点。(The application relates to the technical field of rare earth metal fine and deep product preparation, and particularly discloses a spheroidizing wire and a preparation method thereof. The spheroidizing filament comprises 25-29 parts of magnesium, 1-3 parts of rare earth elements, 23-27 parts of silicon, 3-5 parts of calcium, 1-3 parts of barium, 20-34 parts of manganese powder, 1-3 parts of tungsten powder and 13-23 parts of iron; the preparation method comprises the following steps: smelting, reversing the mould, demoulding, crushing, granulating and coating powder. The spheroidizing wire can be used for steelmaking or casting production, and has the advantages of improving the hardness and impact toughness of castings made of the spheroidizing wire and improving the quality of the castings.)

1. The spheroidizing wire comprises a steel sheet and core powder, and is characterized in that the core powder is prepared from the following raw materials in parts by weight:

25-29 parts of magnesium, 1-3 parts of rare earth elements, 23-27 parts of silicon, 3-5 parts of calcium, 1-3 parts of barium, 20-34 parts of manganese powder, 1-3 parts of tungsten powder and 13-23 parts of iron.

2. The spheroidizing filament according to claim 1, wherein: the traditional Chinese medicine composition is prepared from the following raw materials in parts by weight: 26-28 parts of magnesium powder, 1.5-2.5 parts of rare earth elements, 24-26 parts of silicon, 3.5-4.5 parts of calcium, 1.5-2.5 parts of barium, 24-30 parts of manganese powder, 1.5-2.5 parts of tungsten powder and 16-20 parts of iron.

3. The spheroidizing filament according to claim 1, wherein: the manganese powder is modified manganese powder, and the modified manganese powder is prepared by wrapping magnesium carbonate outside the manganese powder.

4. The spheroidizing filament according to claim 3, wherein: the modified manganese powder is prepared from manganese powder, magnesium carbonate and aminosilane according to the weight ratio (27-29): (1-3): (5-7), wherein the modified manganese powder is prepared by the following steps:

a1, mixing magnesium carbonate and the aminosilane to obtain a mixture;

a2, washing and crushing manganese powder and then heating;

and A3, adding the mixture prepared in the A1 into the heated manganese powder, uniformly mixing, preserving heat and cooling to obtain the modified manganese powder.

5. The spheroidizing filament according to claim 1, wherein: the particle size of the manganese powder is 16-20 mm.

6. A process for producing spheroidized filaments according to any one of claims 1 to 5, characterized in that: the method comprises the following steps:

s1, smelting: weighing magnesium, rare earth elements, silicon, calcium, barium, manganese powder, tungsten powder and iron according to the weight parts, mixing and smelting to obtain alloy molten iron;

s2, reverse mold: pouring the alloy molten iron prepared in the step S1 into a mold and cooling to obtain an alloy iron block;

s3, demolding and crushing: demolding and crushing the alloy iron block prepared in the step S2 to obtain alloy fragments;

s4, granulating: granulating the alloy fragments prepared by the S3 to obtain alloy particles;

s5, powder coating: and (4) coating the alloy particles prepared by the S4 with a steel sheet to obtain the spheroidized wire.

7. The method for preparing spheroidized filaments according to claim 6, wherein the method comprises the following steps: in the step S1, the smelting temperature is controlled to be 1300-1400 ℃.

8. The method for preparing spheroidized filaments according to claim 6, wherein the method comprises the following steps: in the step S4, the grain diameter of the obtained alloy particles is 0.4-0.6 mm.

Technical Field

The application relates to the technical field of rare earth metal fine and deep product preparation, in particular to spheroidized filaments and a preparation method thereof.

Background

The spheroidizing wire is also called spheroidizing core-spun wire, is commonly used in steel making or casting production, and is inserted to a desired position through a wire feeding device. When the surface of the spheroidizing filament is melted, the wire core can be fully dissolved at an ideal position and generates a chemical reaction, the reaction with air and slag is avoided, the form of molten steel inclusions is changed, and the quality of a steel-making casting product is effectively improved.

The spheroidizing wire has various types and is commonly used for producing nodular cast iron, and is prepared by coating core powder with steel sheets, and the core powder in the related technology comprises the following components in percentage by mass: mg: 28-32%, Si: 43-46%, Ca: 2-4%, Ba: 8-10% of Fe and impurities in balance; the nodulizer is used in the nodulizing step in the production process of the nodular cast iron, the amount of cementite forming elements is small, the nodulizing quality is improved, the feeding amount of core-spun yarns is saved, and the production cost is reduced.

Aiming at the related technologies, the inventor thinks that the casting made by the spheroidizing wire in the actual casting production process is easy to produce shrinkage cavity phenomenon, and the casting spheroidizing reaction is not thorough, so that the hardness of the casting is not enough, and the quality of the casting is influenced.

Disclosure of Invention

In order to improve the hardness and impact toughness of castings made of spheroidized wires and improve the quality of the castings, the application provides the spheroidized wires and a preparation method thereof.

In a first aspect, the present application provides a spheroidizing filament, which adopts the following technical scheme:

the spheroidizing wire comprises a steel sheet and core powder, wherein the core powder is prepared from the following raw materials in parts by weight:

25-29 parts of magnesium, 1-3 parts of rare earth elements, 23-27 parts of silicon, 3-5 parts of calcium, 1-3 parts of barium, 20-34 parts of manganese powder, 1-3 parts of tungsten powder and 13-23 parts of iron.

By adopting the technical scheme, the spheroidizing wire promotes the casting to have spheroidization reaction in the casting production, magnesium is used as a main reaction element in the spheroidization reaction, so that the reaction is uniform from top to bottom, the rare earth element slows down the spheroidization recession in the spheroidization reaction, silicon is combined with iron, calcium and barium and is combined with the sulfur, oxygen and other anti-spheroidizing elements in the casting in the spheroidization reaction, so that the casting is spheroidized more completely, manganese powder and tungsten powder are substances with high hardness, the manganese powder and the tungsten powder fill shrinkage cavities generated in the casting spheroidization process, the hardness of the casting is improved, the manganese can be combined with oxygen, and the tungsten can be combined with oxygen and sulfur at high temperature, and the manganese powder is combined with oxygen and the tungsten powder and is combined with oxygen and sulfur in the casting during the spheroidization reaction, so that the oxygen, the sulfur and other anti-spheroidization elements in the casting are further removed, the spheroidization reaction is more complete, and the quality of the casting is improved.

Preferably, the feed additive is prepared from the following raw materials in parts by weight: 26-28 parts of magnesium powder, 1.5-2.5 parts of rare earth elements, 24-26 parts of silicon, 3.5-4.5 parts of calcium, 1.5-2.5 parts of barium, 24-30 parts of manganese powder, 1.5-2.5 parts of tungsten powder and 16-20 parts of iron.

By adopting the technical scheme, the proportion of each component is optimized, the shrinkage cavity phenomenon of the casting is further reduced, the spheroidization reaction of the casting is more complete, the wear-resisting strength and hardness of the casting are improved, and the quality of the casting is improved.

Preferably, the manganese powder is modified manganese powder, and the modified manganese powder is prepared by wrapping magnesium carbonate outside the manganese powder.

By adopting the technical scheme, the magnesium carbonate is used as a dispersing agent to wrap the outer surface of the manganese powder, so that the dispersity of the manganese powder in the casting is improved, the manganese powder is easier to fill shrinkage cavities generated in the casting, and the hardness of the casting is improved; meanwhile, oxygen in the casting can be removed better, and the quality of the casting is improved; in addition, magnesium is an element existing in the spheroidizing wire, and magnesium carbonate is used as a dispersing agent to avoid introducing new impurities as much as possible, so that the quality of the casting is improved.

Preferably, the modified manganese powder is prepared from manganese powder, magnesium carbonate and aminosilane in a weight ratio of (27-29): (1-3): (5-7), wherein the modified manganese powder is prepared by the following steps:

a1, mixing magnesium carbonate and the aminosilane to obtain a mixture;

a2, washing and crushing manganese powder and then heating;

and A3, adding the mixture prepared in the A1 into manganese powder, uniformly mixing, preserving heat and cooling to obtain the modified manganese powder.

By adopting the technical scheme, aminosilane is used as a silane coupling agent and is easy to combine with inorganic matters or metals, and magnesium carbonate and manganese powder are combined through chemical bonds, so that the magnesium carbonate and the manganese powder are combined more tightly, the dispersity of the modified manganese powder is increased beneficially, the modified manganese powder is deoxidized better and is filled in shrinkage cavities generated in castings, the impact toughness and hardness of the castings are improved, and the quality of the castings is improved.

Preferably, the particle size of the manganese powder is 16-20 mm.

By adopting the technical scheme, the manganese powder in the particle size range has better dispersion effect in the casting, and is beneficial to improving the hardness of the casting; if the particle size of the manganese powder is too small, the manganese powder is easy to pollute the environment during transportation, is easy to consume and can stimulate eyes and respiratory mucosa of personnel; if the particle size of the manganese powder is too large, the filling effect of the manganese powder on the shrinkage cavity of the casting can be reduced due to the too large specific surface area of the manganese powder, and the hardness of the casting is further influenced.

In a second aspect, the present application provides a method for preparing spheroidized filaments, which adopts the following technical scheme:

a preparation method of spheroidized filaments comprises the following preparation steps:

s1, smelting: weighing magnesium, rare earth elements, silicon, calcium, barium, manganese powder, tungsten powder and iron according to the weight parts, mixing and smelting to obtain alloy molten iron;

s2, reverse mold: pouring the alloy molten iron prepared in the step S1 into a mold and cooling to obtain an alloy iron block;

s3, demolding and crushing: demolding and crushing the alloy iron block prepared in the step S2 to obtain alloy fragments;

s4, granulating: granulating the alloy fragments prepared by the S3 to obtain alloy particles;

s5, powder coating: and (4) coating the alloy particles prepared by the S4 with a steel sheet to obtain the spheroidized wire.

By adopting the technical scheme, magnesium, rare earth elements, silicon, calcium, barium, manganese powder, tungsten powder and iron are smelted, die-cast, broken by die stripping, granulated and coated to obtain the spheroidized filament, and the prepared spheroidized filament has the functions of filling shrinkage cavities generated in castings, thereby enhancing the impact toughness and hardness of the castings and improving the quality of the castings.

Preferably, in the step S1, the smelting temperature is controlled to be 1300-1400 ℃.

By adopting the technical scheme, when the smelting temperature is controlled at 1300-1400 ℃, the modified manganese powder is in a molten state, so that the modified manganese powder can be better mixed with magnesium, rare earth elements, silicon, calcium, barium, tungsten powder and iron to form more uniform alloy molten iron, and the wear-resisting strength and hardness of the casting are better improved.

Preferably, in the step S4, the obtained alloy particles have a particle size of 0.4-0.6 mm.

By adopting the technical scheme, the grain diameter of the alloy particles is within the range of 0.4-0.6mm, so that the gaps among the alloy particles are reduced, the alloy particles are easier to wrap in a steel sheet, and when the casting is subjected to spheroidization reaction, the smaller alloy particles can quickly act in the casting, so that the time required by the spheroidization reaction of the casting is reduced, and the spheroidization is complete.

In summary, the present application has the following beneficial effects:

1. this application is through adopting specific raw materials ratio, has improved the ability that nodulizing wire takes off anti-spheroidization element in the foundry goods, makes the spheroidization reaction of foundry goods more complete, and this application adds manganese powder and tungsten powder, further takes off anti-spheroidization elements such as oxygen and sulphur in the foundry goods, makes the spheroidization reaction more complete, and manganese powder and tungsten powder can also be used for filling the shrinkage cavity that produces on the foundry goods to the brinell hardness that makes the foundry goods reaches 195.3, improves the foundry goods quality.

2. According to the method, the particle size of the manganese powder is controlled, and the manganese powder is modified by using magnesium carbonate, so that the dispersion effect of the manganese powder in the casting is better, shrinkage cavities generated by the casting can be better filled, the hardness of the prepared casting reaches 201.6, and the hardness of the casting is further improved.

Detailed Description

The present application will be described in further detail with reference to examples.

The starting materials used in the examples are commercially available, with aminosilane available from aminosilane HD-M8252, a firm of Oncor technologies, Inc.

Examples of preparation of raw materials

Preparation example 1

The preparation method of the modified manganese powder comprises the following steps:

a1, mixing 1kg of magnesium carbonate and 5kg of aminosilane to obtain a mixture;

a2, taking 27kg of manganese powder with the grain diameter of 18mm, cleaning, crushing and heating to 110 ℃;

and A3, adding the mixture prepared in the A1 into the heated manganese powder, uniformly mixing, keeping the temperature for 75 minutes, and cooling to room temperature to obtain the modified manganese powder.

Preparation example 2

The preparation method of the modified manganese powder comprises the following steps:

a1, mixing 2kg of magnesium carbonate and 6kg of aminosilane to obtain a mixture;

a2, taking 28kg of manganese powder with the grain diameter of 18mm, cleaning, crushing and heating to 110 ℃;

and A3, adding the mixture prepared in the A1 into the heated manganese powder, uniformly mixing, keeping the temperature for 75 minutes, and cooling to room temperature to obtain the modified manganese powder.

Preparation example 3

The preparation method of the modified manganese powder comprises the following steps:

a1, mixing 3kg of magnesium carbonate and 7kg of aminosilane to obtain a mixture;

a2, taking 29kg of manganese powder with the grain diameter of 18mm, cleaning, crushing and heating to 110 ℃;

and A3, adding the mixture prepared in the A1 into the heated manganese powder, uniformly mixing, keeping the temperature for 75 minutes, and cooling to room temperature to obtain the modified manganese powder.

Preparation example 4

Unlike preparation example 2, the manganese powder had a particle size of 16 mm.

Preparation example 5

Unlike preparation example 2, the manganese powder had a particle size of 20 mm.

Preparation example 6

Unlike preparation example 2, the manganese powder had a particle size of 30 mm.

Preparation example 7

Unlike preparation example 2, preparation example 7 uses an equal amount of magnesium phosphate instead of magnesium carbonate.

Preparation example 8

In contrast to preparation example 2, preparation example 8 used an equivalent amount of calcium carbonate instead of magnesium carbonate.

Preparation example 9

In contrast to preparation 2, preparation 9 used an equivalent amount of vinyltriethoxysilane instead of aminosilane.

Preparation example 10

Unlike preparation 2, preparation 10 uses the same amount of epoxy silane crosslinking agent in place of the aminosilane.

Examples

Example 1

A spheroidized filament, the preparation method comprises:

s1, smelting: mixing and smelting 25kg of magnesium, 1kg of rare earth elements, 23kg of silicon, 3kg of calcium and 1kg of barium, 27kg of manganese powder with the particle size of 18mm, 2kg of tungsten powder and 13kg of iron at the high temperature of 1300 ℃ to obtain molten alloy iron;

s2, reverse mold: pouring the alloy molten iron prepared in the step S1 into a mold and cooling to obtain an alloy iron block;

s3, demolding and crushing: demolding and crushing the alloy iron block prepared in the step S2 to obtain alloy fragments;

s4, granulating: preparing the alloy fragments prepared by the S3 into alloy particles with the particle size of 0.4 mm;

s5, powder coating: and (4) coating the alloy particles prepared by the S4 with a steel sheet to obtain the spheroidized wire.

Examples 2 to 5

Different from example 1, the raw material ratios for preparing spheroidized filaments in examples 2 to 5 are different, and the details are shown in Table 1.

TABLE 1 raw material ratios of examples 1-5

Examples	Magnesium/kg	Rare earth element/kg	Silicon/kg	Calcium/kg	Barium/kg	Manganese powder/kg	Tungsten powder/kg	Iron/kg	Manganese powder particle size/mm	Alloy particle size/mm
											Example 1	25	1	23	3	1	27	2	13	18	0.4
Example 2	27	2	25	4	2	27	2	18	18	0.4
											Example 3	29	3	27	5	3	27	2	23	18	0.4
Example 4	26	1.5	24	3.5	1.5	27	2	16	18	0.4
											Example 5	28	2.5	26	4.5	2.5	27	2	20	18	0.4

Examples 6 to 15

In contrast to example 2, examples 6 to 15 each replaced the manganese powder with an equal amount of the modified manganese powder from preparations 1 to 10.

Example 16

A spheroidized wire, different from example 2, was melted at 1400 ℃ in S1 to obtain alloy particles having a particle size of 0.6 mm.

Comparative example

Comparative example 1

A spheroidized wire, which is different from example 2 in that the tungsten powder was replaced with the same amount of manganese powder in comparative example 1.

Comparative example 2

A spheroidized wire was different from example 2 in that the manganese powder was replaced with the same amount of tungsten powder in comparative example 2.

Comparative example 3

A spheroidized wire, which is different from example 2 in that manganese powder and tungsten powder are not added to the raw material.

Performance test

The spheroidizing wires of examples 1 to 15 and comparative examples 1 to 3 are used in the production and processing of castings of the same process and formula to prepare castings. The following performance tests were performed on the finished castings. The performance test includes the impact toughness and hardness of the casting, and the test data is shown in Table 2.

1. Hardness of

And (3) detecting the hardness of the casting made of the spheroidizing wire according to the detection standard of the national standard GB/T231.1-2018 Brinell hardness test of metal materials. The detection environment is as follows: at 23 ℃.

2. Impact toughness

And detecting the hardness of the casting made of the spheroidizing wire according to the detection standard of the national standard GB/T1817-2017 test method for the normal temperature impact toughness of the hard alloy. The detection environment is as follows: at 23 ℃.

Table 2 table of performance testing data

	Brinell hardness HBW	Impact toughness J/cm2
			Example 1	192.8	9.47
Example 2	195.3	9.87
			Example 3	193.2	9.51
Example 4	194.7	9.58
			Example 5	194.9	9.67
Example 6	201.2	10.29
			Example 7	201.6	10.38
Example 8	200.7	10.25
			Example 9	200.9	10.27
Example 10	200.7	10.23
			Example 11	199.5	10.09
Example 12	199.6	10.13
			Example 13	199.4	10.05
Example 14	198.8	10.07
			Example 15	198.5	10.01
Example 16	195.5	9.91
			Comparative example 1	185.3	8.91
Comparative example 2	186.7	8.95
			Comparative example 3	162.4	7.82

The present application is described in detail below with reference to the test data provided in table 2.

Combining comparative examples 1-3 and examples 1-16, it was found that castings produced using the spheroidizing wires of examples 1-16 of the present application had better brinell hardness and impact toughness than comparative examples 1-3, indicating that the spheroidizing wires of the present application perform better in increasing the hardness and impact toughness of the castings.

The addition ratios of the raw materials were compared in examples 1 to 5. As a result, it was found that the casting produced using the spheroidized wire of example 2 had better brinell hardness and impact toughness, which indicates that the raw material ratio of the spheroidized wire of example 2 was better.

Combining example 2 with comparative examples 1-3, it was found that in comparative example 1, no tungsten powder was added to the feedstock and the brinell hardness and impact toughness of the castings were lower than those of example 2; in comparative example 2, no manganese powder was added to the raw materials, and the brinell hardness and impact toughness of the castings were lower than those of example 2; in comparative example 3, no manganese powder and tungsten powder were added to the raw materials, and the brinell hardness and impact toughness of the castings were lower than those of example 2; this is probably because the manganese powder and the tungsten powder are mutually matched, and shrinkage cavities in the casting can be better filled, so that the hardness and the impact toughness of the casting are improved.

The present application examined the effect of modified manganese powder in examples 6-15, using example 2 as a control. As a result, the Brinell hardness and the impact toughness of the castings of examples 6 to 15 are superior to those of example 2, probably because the manganese powder is modified to improve the dispersibility of the manganese powder, so that the manganese powder can better fill the shrinkage cavity of the castings, and further the quality of the castings is improved.

The present application examined the effect of the particle size of the modified manganese powder in examples 9-11, using example 7 as a control. The results show that the casting of example 11 has a lower brinell hardness and lower impact toughness than those of examples 7 and 9-10, which indicates that manganese powders in the particle size range of the present application have a better effect.

The present application examined the effect of different dispersants on the modification of manganese powder in examples 11 and 12, using example 7 as a control. As a result, in example 11, since magnesium carbonate was replaced with magnesium phosphate in an equivalent amount, the Brinell hardness and impact toughness of the casting were low; in example 12, the magnesium carbonate is replaced by the same amount of calcium carbonate, so that the Brinell hardness and the impact toughness of the cast are lower, and example 7 is better, which shows that the magnesium carbonate is used for transforming the manganese powder to achieve better effect.

The present application examined the effect of different silane coupling agents in examples 13 and 14, using example 7 as a control. As a result, in example 13, the Brinell hardness and impact toughness of the casting were low because the aminosilane in the modified manganese powder was replaced with the same amount of vinyltriethoxysilane; in example 14, the magnesium powder is modified by replacing aminosilane in the modified manganese powder with an equal amount of epoxy silane cross-linking agent, so that the Brinell hardness and impact toughness of the casting are lower, and example 7 is better, which shows that the aminosilane and magnesium carbonate are matched to achieve a better effect of modifying the manganese powder.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.