CN113186419B - Refining agent for brass smelting and brass casting method - Google Patents
Refining agent for brass smelting and brass casting method Download PDFInfo
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- CN113186419B CN113186419B CN202110405181.6A CN202110405181A CN113186419B CN 113186419 B CN113186419 B CN 113186419B CN 202110405181 A CN202110405181 A CN 202110405181A CN 113186419 B CN113186419 B CN 113186419B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/06—Making non-ferrous alloys with the use of special agents for refining or deoxidising
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C9/00—Alloys based on copper
- C22C9/01—Alloys based on copper with aluminium as the next major constituent
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Abstract
The invention discloses a refining agent for brass smelting, which is characterized by comprising the following components in parts by weight: the refining agent comprises the following components in percentage by mass: 5% -20%, potassium chloride: 10% -30%, sodium carbonate: 10% -30%, cryolite: 5% -20%, sodium aluminate: 5 to 10 percent, and the balance of dolomite and inevitable impurities. According to the invention, by controlling the addition amounts of dolomite, quartz sand, potassium chloride, sodium carbonate, cryolite and sodium aluminate, the melt of the copper alloy is purified, the problems of sand holes and pin holes of the blank are greatly eliminated, and the air tightness quality of the casting blank is improved.
Description
Technical Field
The invention relates to a refining agent for smelting brass and a brass casting method.
Background
The inflating valve is also called as an airtight valve and mainly comprises the inflating valve and a sealing piece, wherein the inflating valve is a machined part, the raw materials are copper materials and aluminum materials, and the raw material of the sealing piece is a rubber material, is used for air inlet of a tire and preventing air leakage of the tire, and is an indispensable safety part in the automobile industry. The valve is usually made of brass, because brass has excellent cutting performance and ductility, but copper products are easy to corrode in use and react with oxygen, carbon dioxide, water and other substances in air to generate Cu2(OH)2CO3For short, verdigris, so the surface treatment of the copper product can be carried out, and the common modes comprise nickel plating, chromium plating and the like. Through the rapid development of more than ten years, the valve industry in China has dominated the world. At present, the output of the inflating valve in China accounts for more than seven percent of the total output of the inflating valve in the world, and is the top list of the output and the sales of the inflating valve in the world. In order to meet the requirements of domestic and international markets, the tubeless inflating valve is gradually increased, and the yield of the tubeless inflating valve accounts for more than half of the total yield of the inflating valve in 2015. The industry development is continuously promoted by huge domestic market demands, along with the high-speed development of domestic economy, the demands for the inflating valve are increased explosively in the future, and the improvement of the quality of the inflating valve product is a powerful weapon for seizing the market segment.
For the valve, the common brass alloy grades mainly comprise HPb59-1, HPb59-2, HPb60-2, HPb63-0.1, H62 and H65. The air tightness quality of the blank is most important for the safety of the inflating valve, and the air tightness quality is mainly related to the problems of the sand holes and the pin holes of the brass blank for the inflating valve, because the air tightness and the pressure maintaining conditions of tires can be directly influenced, the inflating valve brass with the sand holes and the pin holes can cause great potential safety hazards to the driving process of bicycles and automobiles, and the sand holes and the pin holes can cause poor smoothness of the brass surface and easily generate corrosion, so that the product quality needs to be ensured from a material source, and the problems of the sand holes and the pin holes of the blank are greatly eliminated; the sand holes are mainly obtained from the casting process of materials, impurities of a melt are not completely refined in the casting process, so that easily corroded oxides such as siliceous, calcareous and iron exist in blanks, meanwhile, the existence of gas in the melt also causes a large amount of clustered fine needle-shaped air holes, and the fine needle-shaped air holes need to be polished for discovery, so that the development of the refining agent for the brass smelting of the valve is urgent.
Disclosure of Invention
The invention aims to solve the first technical problem of providing a refining agent for smelting brass, which can purify a copper alloy melt and improve the purity of the melt.
The technical scheme adopted by the invention for solving the first technical problem is as follows: a refining agent for brass smelting is characterized in that: the refining agent comprises the following components in percentage by mass: 5% -20%, potassium chloride: 10% -30%, sodium carbonate: 10% -30%, cryolite: 5% -20%, sodium aluminate: 5 to 10 percent, and the balance of dolomite and inevitable impurities.
Dolomite: degassing, and taking away gas and oxidation slag in the copper water by using carbon dioxide bubbles through the decomposition of carbonate.
Quartz sand: the method is mainly used for carrying out chemical combination reaction with metal oxide, namely slagging reaction, forming oxide with low density, floating on the surface of a melt and playing the roles of removing impurities and stabilizing slag. Less than 5% of the slag-forming effect is insufficient, and more than 20% of the slag-forming effect generates excessive SiO2Increasing the content of CaO-Al in the slag system2O3-SiO2Resulting in excessive mechanical inclusions.
Potassium chloride: the chlorine salt is added mainlyFormation of AlCl3When the addition amount is more than 30%, the effect of removing aluminum impurities does not contribute to the reaction, and only the viscosity of the slag is increased.
Sodium carbonate: the sodium carbonate is characterized in that decomposed sodium oxide and carbon dioxide act on a melt, the sodium oxide can carry out most of silicon oxide, iron oxide and the like, when the addition amount of the sodium carbonate is more than 30%, the excessive sodium oxide can increase the viscosity of slag to form a glassy compound, and when the addition amount of the sodium carbonate is less than 10%, slagging is insufficient, and the effect is poor.
Cryolite: the slag system is softened, the slagging reaction is convenient to carry out, the fluorine salt has the function of improving the fluidity of the slag, namely, the melting point of the slag is reduced, and when the addition amount of the cryolite is more than 20 percent, the melting point of the slag system is improved.
Sodium aluminate: the catalyst for slagging reaction can separate out chlorate ions in a molten state, adsorb oxides in the melt, enable the oxides to be gathered and float out of the melt, and react with other silicate and carbonate for slagging reaction, when the addition amount of sodium aluminate is higher than 10%, the catalytic action is not obvious, and when the addition amount is lower than 5%, the catalytic action amount is not enough.
The second technical problem to be solved by the invention is to provide a brass casting method.
The technical scheme adopted by the invention for solving the second technical problem is as follows: a brass casting method is characterized by comprising the following steps:
1) preparing materials: mixing the raw materials according to the components required by the brass, wherein the raw materials comprise the refining agent;
2) smelting: adding 15-25 wt% of the total mass of the refining agent in the smelting process, wherein the smelting temperature is 1020-1080 ℃;
3) slag fishing: adding a slag removing agent, stirring and fishing slag, refining after the slag is fished, pressing the rest refining agent into the molten copper, stirring the molten copper for 0.5-5 min, and standing for 1-10 min;
4) thinning: adding a refiner, wrapping the refiner by using copper foil, pressing the refiner into copper water, adding the refiner, stirring for 1-5 min, and standing for 5-10 min after stirring;
5) casting: the casting temperature is 1000-1050 ℃.
The brass comprises returned materials and leftover materials accounting for about 30 wt%, more oxides and oil are contained, and more impurities are brought in, the refining agent is added twice, part of the refining agent can react with the oxides in furnace materials in advance by adding twice, slagging is carried out, namely refining pretreatment is carried out, 15-25 wt% of the total mass of the refining agent is added during pretreatment, the activity of the oxides in a melt or the activity of gas possibly existing in the melt can be reduced, and the effect of deep refining can be achieved by subsequent refining.
Preferably, the amount of the refining agent in the step 1) is 1-1.5% of the total mass of the brass ingredients.
Compared with the prior art, the invention has the advantages that: according to the invention, by controlling the addition amounts of dolomite, quartz sand, potassium chloride, sodium carbonate, cryolite and sodium aluminate, the melt of the copper alloy is purified, the problems of sand holes and pin holes of the blank are greatly eliminated, and the air tightness quality of the casting blank is improved.
Drawings
FIG. 1 is a photograph of the finished bar of example 1 of the present invention after polishing.
FIG. 2 is an electronic scanning photograph of example 1 of the present invention;
FIG. 3 is an electron scan photograph of an ingot of a comparative example of the present invention; wherein 1 is a hard particle in the ingot.
FIG. 4 is an enlarged view of FIG. 3; wherein 1 is a hard particle in the ingot.
FIG. 5 is a power spectrum of the hard particles of FIG. 4; wherein, the graph (a) is an energy spectrum graph, and the graph (b) is the content of each element in the energy spectrum graph.
Detailed Description
The invention is described in further detail below with reference to the accompanying examples.
Example 1
Taking HPb59-1 as an example, the refining agent comprises the following components in percentage by mass: the balance; quartz sand: 5 percent; potassium chloride: 10 percent; sodium carbonate: 30 percent; cryolite: 10 percent; sodium aluminate: 5 percent. The addition amount of the refining agent is 1 percent of the total amount of the HPb59-1 ingredient.
A casting method of HPb59-1, comprising the steps of:
1) preparing materials: preparing materials according to the components required by HPb59-1, wherein the raw materials comprise 40% of waste red copper, 30% of copper return material, 30% of leftover material, zinc block, lead block, magnesium block, covering agent, refining agent and the like;
2) smelting: mixing 20% of the total mass of the refining agent with partial copper return materials and leftover materials, adding the mixture into a power frequency furnace, gradually adding partial zinc blocks in the melting process, adding waste red copper after melting, adding residual copper return materials and leftover materials after the waste red copper is melted, testing components after all the materials are completely melted, adding zinc blocks and lead blocks for balancing, simultaneously adding a small amount of magnesium blocks in an auxiliary manner, and performing fire spraying operation under high pressure until the temperature reaches 1050 ℃;
3) slag fishing: flaming for 1-2 min, adding a slag removing agent, stirring and dragging slag, refining after dragging slag, pressing the remaining 80% of the refining agent into the copper water by using an iron spoon, stirring the copper water for about 1min after violent reaction is finished, and standing for 3 min;
4) thinning: spraying fire at high pressure, adding a refiner accounting for 0.03% of the total mass of the ingredients after the fire spraying, wrapping the refiner by using copper foil, pressing the refiner into copper water, stirring for 2min, and standing for 8min after the stirring is finished;
5) casting: the temperature is measured to 1020 ℃ and then casting can be carried out;
example 2
Taking HPb60-2 as an example, the refining agent comprises the following components in percentage by mass: the balance; quartz sand: 5 percent; potassium chloride: 10 percent; sodium carbonate: 25 percent; cryolite: 10 percent; sodium aluminate: 5 percent. The addition amount of the refining agent is 1.2 percent of the total amount of the HPb60-2 ingredient.
A casting method of HPb60-2, comprising the steps of:
1) preparing materials: preparing materials according to the components required by HPb60-2, wherein the raw materials comprise 40% of waste red copper, 30% of copper return material, 30% of leftover material, zinc block, lead block, magnesium block, covering agent, refining agent and the like;
2) smelting: mixing 20% of the total mass of the refining agent with part of copper return materials and leftover materials, adding the mixture into a power frequency furnace, gradually adding part of zinc blocks in the melting process, adding waste red copper after melting, adding the rest copper return materials and leftover materials after the waste red copper is melted, testing components after all the materials are completely melted, adding zinc blocks and lead blocks for balancing, simultaneously adding a small amount of magnesium blocks in an auxiliary manner, and performing fire spraying operation under high pressure at the temperature of 1080 ℃;
3) slag fishing: flaming for 1-2 min, adding a slag removing agent, stirring and dragging slag, refining after dragging slag, pressing the remaining 80% of the refining agent into the copper water by using an iron spoon, stirring the copper water for about 1min after violent reaction is finished, and standing for 3 min;
4) thinning: spraying fire at high pressure, adding a refiner accounting for 0.03% of the total mass of the ingredients after the fire spraying, wrapping the refiner by using copper foil, pressing the refiner into copper water, stirring for 2min, and standing for 8min after the stirring is finished;
5) casting: and the temperature is measured to 1050 ℃ and then the casting can be carried out.
Example 3
Taking HPb59-2 as an example, the refining agent comprises the following components in percentage by mass: the balance; quartz sand: 5 percent; potassium chloride: 15 percent; sodium carbonate: 20 percent; cryolite: 10 percent; sodium aluminate: 5 percent. The addition amount of the refining agent is 1.5 percent of the total amount of the HPb59-2 ingredient.
1) Preparing materials: preparing materials according to the components required by HPb59-2, wherein the raw materials comprise 40% of waste red copper, 30% of copper return material, 30% of leftover material, zinc blocks, magnesium blocks, covering agents, refining agents and the like;
2) smelting: mixing 20% of the total mass of the refining agent with part of copper return materials and leftover materials, adding the mixture into a power frequency furnace, gradually adding part of zinc blocks in the melting process, adding waste red copper after melting, adding the rest copper return materials and leftover materials after the waste red copper is melted, testing components after all the materials are completely melted, adding the zinc blocks for balancing, simultaneously adding a small amount of magnesium blocks in an auxiliary manner, and performing fire spraying operation under high pressure at the temperature of 1080 ℃;
3) slag fishing: flaming for 1-2 min, adding a slag removing agent, stirring and dragging slag, refining after dragging slag, pressing the remaining 80% of the refining agent into the copper water by using an iron spoon, stirring the copper water for about 1min after violent reaction is finished, and standing for 3 min;
4) thinning: spraying fire at high pressure, adding a refiner accounting for 0.03% of the total mass of the ingredients after the fire spraying, wrapping the refiner by using copper foil, pressing the refiner into copper water, stirring for 2min, and standing for 8min after the stirring is finished;
5) casting: and (5) casting when the temperature reaches 1100 ℃.
Comparative example: the mass percentage composition of the refining agent is as follows: 60 wt% of sodium carbonate, 20 wt% of NaCl, 10 wt% of cryolite and 10 wt% of silicon dioxide.
Taking HPb59-1 as an example, the mass percentage of the refining agent is as follows: 60 wt% of sodium carbonate, 20 wt% of NaCl, 10 wt% of cryolite and 10 wt% of silicon dioxide. The addition amount of the refining agent is 1 percent of the total amount of the HPb59-1 ingredient.
A casting method of HPb59-1, comprising the steps of:
1) preparing materials: preparing materials according to the components required by HPb59-1, wherein the raw materials comprise 40% of waste red copper, 30% of copper return material, 30% of leftover material, zinc block, lead block, magnesium block, covering agent, refining agent and the like;
2) smelting: mixing 20% of the total mass of the refining agent with partial copper return materials and leftover materials, adding the mixture into a power frequency furnace, gradually adding partial zinc blocks in the melting process, adding waste red copper after melting, adding residual copper return materials and leftover materials after the waste red copper is melted, testing components after all the materials are completely melted, adding zinc blocks and lead blocks for balancing, simultaneously adding a small amount of magnesium blocks in an auxiliary manner, and performing fire spraying operation under high pressure until the temperature reaches 1050 ℃;
3) slag fishing: flaming for 1-2 min, adding a slag removing agent, stirring and dragging slag, refining after dragging slag, pressing the remaining 80% of the refining agent into the copper water by using an iron spoon, stirring the copper water for about 1min after violent reaction is finished, and standing for 3 min;
4) thinning: spraying fire at high pressure, adding a refiner accounting for 0.03% of the total mass of the ingredients after the fire spraying, wrapping the refiner by using copper foil, pressing the refiner into copper water, stirring for 2min, and standing for 8min after the stirring is finished;
5) casting: casting when the temperature reaches 1020 ℃;
the ingot compositions of the examples and comparative examples are shown in Table 1.
Referring to fig. 2, hard particles are not observed in the electron scanning photograph of the ingot casting of example 1 of the present invention, which shows that the refining agent of the present invention is used to remove impurities and clean the matrix, the surface of the bar is polished, as shown in fig. 1, the polished surface of the bar is smooth, and no sand holes or air holes are observed in the reflected light.
Referring to fig. 3, in the electronic scanning photograph of the ingot of the comparative example, a plurality of hard spots distributed on the matrix are observed, the hard spots are amplified, and as shown in fig. 4, the hard spots are subjected to energy spectrum analysis and are slag inclusions such as silicon dioxide, iron and the like, which indicates that the matrix is incompletely purified by using the refining agent of the comparative example.
TABLE 1 Brass composition of inventive and comparative examples
Claims (3)
1. A refining agent for brass smelting is characterized in that: the refining agent comprises the following components in percentage by mass: 5% -20%, potassium chloride: 10% -30%, sodium carbonate: 10% -30%, cryolite: 5% -20%, sodium aluminate: 5 to 10 percent, and the balance of dolomite and inevitable impurities.
2. A brass casting method is characterized by comprising the following steps:
1) preparing materials: compounding brass in accordance with the desired composition, including the refining agent of claim 1;
2) smelting: adding 15-25 wt% of the total mass of the refining agent in the smelting process, wherein the smelting temperature is 1020-1080 ℃;
3) slag fishing: adding a slag removing agent, stirring and fishing slag, refining after the slag is fished, pressing the rest refining agent into the molten copper, stirring the molten copper for 0.5-5 min, and standing for 1-10 min;
4) thinning: adding a refiner, wrapping the refiner by using copper foil, pressing the refiner into copper water, adding the refiner, stirring for 1-5 min, and standing for 5-10 min after stirring;
5) casting: the casting temperature is 1000-1050 ℃.
3. The brass casting method of claim 2, wherein: the amount of the refining agent in the step 1) is 1-1.5% of the total mass of the brass ingredients.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2017084A1 (en) * | 1968-08-29 | 1970-05-15 | Int Nickel Ltd | Cupronickel alloy welding without subsequent ageing |
| SU899698A1 (en) * | 1977-07-21 | 1982-01-23 | Институт Проблем Литья Ан Укрсср | Method for refining and modifying aluminium and silicon alloys |
| SU1661235A1 (en) * | 1989-06-05 | 1991-07-07 | Всесоюзный научно-исследовательский проектно-конструкторский и технологический институт электромашиностроения | Flux for treating aluminium-silicon alloys |
| CN102605205A (en) * | 2012-03-22 | 2012-07-25 | 金川集团有限公司 | Brass alloy smelting method |
| CN104775042A (en) * | 2015-04-16 | 2015-07-15 | 新疆大学 | Low-metal-loss smelting method of copper alloy |
| CN107217172A (en) * | 2017-06-28 | 2017-09-29 | 安徽华飞机械铸锻有限公司 | One Albatra metal casting technique |
| CN109554563A (en) * | 2019-01-23 | 2019-04-02 | 北京科技大学 | A method of reducing complicated pluralism brass alloys impurity element nickel |
-
2021
- 2021-04-15 CN CN202110405181.6A patent/CN113186419B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2017084A1 (en) * | 1968-08-29 | 1970-05-15 | Int Nickel Ltd | Cupronickel alloy welding without subsequent ageing |
| SU899698A1 (en) * | 1977-07-21 | 1982-01-23 | Институт Проблем Литья Ан Укрсср | Method for refining and modifying aluminium and silicon alloys |
| SU1661235A1 (en) * | 1989-06-05 | 1991-07-07 | Всесоюзный научно-исследовательский проектно-конструкторский и технологический институт электромашиностроения | Flux for treating aluminium-silicon alloys |
| CN102605205A (en) * | 2012-03-22 | 2012-07-25 | 金川集团有限公司 | Brass alloy smelting method |
| CN104775042A (en) * | 2015-04-16 | 2015-07-15 | 新疆大学 | Low-metal-loss smelting method of copper alloy |
| CN107217172A (en) * | 2017-06-28 | 2017-09-29 | 安徽华飞机械铸锻有限公司 | One Albatra metal casting technique |
| CN109554563A (en) * | 2019-01-23 | 2019-04-02 | 北京科技大学 | A method of reducing complicated pluralism brass alloys impurity element nickel |
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