Production method of zinc-aluminum-magnesium-nickel-titanium-boron rare earth alloy

Abstract

The invention belongs to the technical field of metallurgy, and particularly relates to a production method of a zinc-aluminum-magnesium-nickel-titanium-boron rare earth alloy. According to the method, by optimizing the adding mode of multi-element high-melting-point alloy elements, zinc sheets, batched aluminum ingots, zinc-nickel alloy, sponge titanium, rare earth lanthanum-cerium alloy, boron powder and magnesium ingots are sequentially added in a specific temperature interval and melted through electromagnetic stirring, and finally the zinc-aluminum-magnesium-nickel-titanium-boron rare earth alloy is obtained after slagging is conducted through a slagging constituent and casting is conducted. According to the method, through the steps of two-time aluminum melting and post magnesium adding, accurate heat management in the melting process is achieved, the burn-out rate of the magnesium element is reduced to 2.18%, nickel and titanium metal is replaced with the zinc-nickel alloy and the sponge titanium, rapid adding of high-melting-point elements is achieved, the melting time is shortened, energy consumption is reduced, and alloy components are more uniform. By using the novel slag former, the dual effects of physical covering and adsorption are achieved, the slag removal effect is effectively improved, and the metal direct recovery rate of the obtained seven-element alloy can reach 98%.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metallurgy, in particular to a zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy for high-end coating and a production method thereof. BACKGROUND

[0002] Traditional zinc-aluminum-magnesium alloy has good corrosion resistance, but during solidification, it is easy to form coarse dendrites or zinc-rich / aluminum-rich phases, which seriously affects the mechanical properties and processing performance of the alloy. To meet the requirements of high-end coating field on plate strength, formability and longer service life, micro-alloying technology is usually used to optimize alloy performance by adding specific elements. Among them, nickel can enhance the bonding force between the coating and the iron base and improve the fatigue resistance; titanium and boron as grain refiners can significantly improve the mechanical properties of the alloy and refine the grains; rare earth elements can purify the melt and further enhance the corrosion resistance of the alloy.

[0003] However, the physical properties of the above alloy elements differ greatly, and the melting temperature of zinc-aluminum-magnesium alloy is usually between 550℃ and 650℃, while the melting points of nickel, titanium and boron are as high as 1453℃, 1668℃ and 2079℃ respectively. When using conventional melting process, high-melting-point elements such as nickel, titanium and boron are difficult to melt uniformly, are prone to composition segregation, and the alloy composition control is extremely unstable. Moreover, the melting process is usually highly exothermic and the temperature is too high, resulting in a large amount of magnesium element burning loss and volatilization, which cannot achieve industrialized high-quality production.

[0004] In addition, ammonium chloride is commonly used as a slag former in the production process of zinc-aluminum-magnesium alloy. The boiling point of ammonium chloride is relatively low, and it will quickly turn into gas after being added to the melt, which cannot form a stable liquid flux layer on the surface of the melt that can continuously adsorb oxides, resulting in poor deslagging effect and low direct yield of the alloy. SUMMARY

[0005] In view of the problems in the background art, the purpose of the present application is to provide a production method of zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy. The method solves the problem of uniform melting and burning loss of multi-element high-melting-point alloy elements in the low-melting-point zinc-aluminum-magnesium alloy matrix by innovatively designing the melting and slagging process, effectively improving the direct yield of the alloy.

[0006] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows: A production method of zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy, characterized in that it comprises the following steps: S1: using a pusher to add zinc sheets to a No. 1 electric furnace and melting at 500-550℃, adding ammonium chloride to form slag, and then transferring the molten zinc liquid to a No. 2 electric furnace through a chute; S2: The aluminum ingots are evenly divided into two batches by weight, and are sequentially added into the No. 2 electric furnace, with the temperature controlled at 700-800℃, and the melting is assisted by stirring. After the first batch of aluminum ingots is completely melted, the second batch of aluminum ingots is added until completely melted; S3: After the aluminum is completely melted, the zinc-nickel alloy is added into the No. 2 electric furnace, with the temperature controlled at 800-850℃, and the melting is assisted by stirring until completely melted; S4: The temperature is maintained at 800-850℃, and the titanium sponge is added into the No. 2 electric furnace, and the melting is assisted by stirring until completely melted; S5: The temperature is reduced to 650-700℃, and the rare earth lanthanum-cerium alloy is added into the No. 2 electric furnace, and the melting is assisted by stirring until completely melted; S6: The temperature is maintained at 650-700℃, and the boron powder is added into the No. 2 electric furnace, and the melting is assisted by stirring until completely melted; S7: The magnesium ingot is added into the No. 2 electric furnace, and the melting is assisted by stirring at the temperature of 650-700℃ until completely melted, and finally the alloy liquid with uniform composition is formed; S8: The slagging agent is added into the No. 2 electric furnace, and then the starch is added on the surface, and the starch is ignited, and the slagging is assisted by stirring to obtain the powder-shaped alloy slag, and the powder-shaped alloy slag is fished to the slag box to complete the slag cleaning; S9: The alloy melt after the slag cleaning is sampled and analyzed, and after confirming that the content is qualified, the No. 2 electric furnace is poured, and the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy liquid is poured out, and the pouring channel is used for casting, and after cooling, the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy ingot is obtained.

[0007] Preferably, the pusher in S1 adds the zinc sheet into the No. 1 electric furnace at a rate of 200-300kg / time, and the amount of the added ammonium chloride is 3-5kg / 10 tons of zinc sheet.

[0008] Preferably, the zinc-nickel alloy in S3 includes 0.9%-1.1% of nickel by mass percentage, and the balance is zinc.

[0009] Preferably, the titanium sponge in S4 includes 99.1%-99.7% of titanium by mass percentage, and the balance is iron, silicon, chlorine, carbon, nitrogen, oxygen, manganese, magnesium, hydrogen, nickel, and chromium.

[0010] Preferably, the rare earth lanthanum-cerium alloy in S5 includes 63%-67% of cerium by mass percentage, and the balance is lanthanum.

[0011] Preferably, the slagging agent in S8 mainly includes cryolite powder, zinc chloride, magnesium chloride, and sodium chloride, and the weight ratio of the cryolite powder, the zinc chloride, the magnesium chloride, and the sodium chloride is 40-45:35-40:5-10:10-15, and the amount of the added slagging agent is 5-8kg / 10 tons of alloy liquid, and the amount of the added starch is 5kg / 10 tons of alloy liquid.

[0012] Preferably, the first electric furnace in S1 is a core induction furnace, and the second electric furnace in S1 to S9 is a coreless induction furnace.

[0013] Preferably, the stirring mode in S1 to S8 is electromagnetic stirring.

[0014] Preferably, the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy in S9 comprises, by mass percentage, 10%-12% of aluminum, 2%-3% of magnesium, 0.1%-0.2% of nickel, 0.05%-0.1% of boron, 0.08%-0.1% of titanium, and 0.08%-0.1% of rare earth elements, with the balance being zinc.

[0015] The present application has the following advantages: The melting point of the zinc-nickel alloy is generally between 700℃ and 900℃, close to the alloy smelting temperature; the sponge titanium has a porous sponge structure and a high specific surface area, and can rapidly penetrate the alloy matrix; the aluminum-rich end and the zinc-rich end of boron can form intermetallic compounds AlB2 and ZnB2; by utilizing the above properties, the high-melting-point elements nickel, titanium, and boron can be rapidly melted and added into the alloy melt at a lower temperature, significantly shortening the smelting period and reducing energy consumption. By adding aluminum in batches and adding magnesium at the end, precise thermal management of the smelting process is achieved, reducing the oxidation and burning loss of magnesium.

[0016] The present method uses a new slag former with low melting point and specific gravity, which rapidly melts and forms a thin liquid film on the surface of the melt during the slagging process, floats on the alloy, effectively isolates air, and reduces the continuous oxidation of the alloy. And add organic matter to assist slagging, use the heat generated by the combustion of organic matter to increase the interface temperature of the slagging reaction, reduce the surface tension of the floating slag, improve the separation effect, and the carbonized organic matter has a porous structure that can adsorb non-metallic inclusions in the alloy liquid, effectively improving the direct yield of the alloy through the dual mechanisms of physical covering and adsorption.

[0017] The alloy ingot produced by the present method has fine grains, high hardness, good mechanical processing performance, and strong fatigue resistance, meeting the requirements of high-end plates. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 The present application is implemented as a flowchart; Figure 2 The present application is implemented as a flowchart; Figure 3 The present application is implemented as a flowchart; DETAILED DESCRIPTION

[0019] EXAMPLE The amount and mass percentage of the alloy raw materials added in this example are as follows: The slag forming agent used in the embodiment includes cryolite powder, zinc chloride, magnesium chloride, sodium chloride, and the weight ratio of the cryolite powder, zinc chloride, magnesium chloride, and sodium chloride is 42:38:8:12, and the amount used is 6 kg.

[0020] The power of the core induction furnace used in the embodiment is 45 t / 720 KW, and the power of the coreless induction furnace is 10 t / 600 KW.

[0021] The zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy plate produced in the embodiment includes the following steps: S1: The zinc sheet is added into the core induction furnace at a rate of 250 kg / time using a pushing machine, melted at 520°C, and 4.0 kg of ammonium chloride is added to form slag, and then the molten zinc liquid is transferred into the coreless induction furnace through a trough as the base furnace for the subsequent steps; S2: The aluminum ingot is evenly divided into two batches according to the weight, and is sequentially added into the coreless induction furnace, and the temperature is controlled at 750°C, and the melting is assisted by electromagnetic stirring, and after the first batch of aluminum ingot is completely melted, the second batch of aluminum ingot is added until it is completely melted; S3: After the aluminum is completely melted, the zinc-nickel alloy is added into the furnace, and the temperature is controlled at 820°C, and the complete melting is achieved through electromagnetic stirring; S4: The temperature is maintained at 820°C, and then the titanium sponge is added into the furnace, and the complete melting is achieved through electromagnetic stirring; S5: The temperature is reduced to 670°C, and then the rare earth lanthanum-cerium alloy is added, and the complete melting is achieved through electromagnetic stirring; S6: The temperature is maintained at 670°C, and then the boron powder is added into the furnace, and the complete melting is achieved through electromagnetic stirring; S7: Finally, the magnesium ingot is added into the furnace, and is still stirred at the temperature of 670°C until it is completely melted, and finally the alloy liquid with uniform composition is formed; S8: 6 kg of slag forming agent is added into the coreless induction furnace, and then 5 kg of starch is added on the surface, and the starch is ignited, and the powder alloy slag is obtained through sufficient stirring, and finally the powder alloy slag is salvaged into the slag box using a robot, and the slag cleaning process is completed; S9: The alloy melt after slag cleaning is sampled and analyzed, and after confirming that the content is qualified, the coreless induction furnace is poured, and the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy liquid is poured out, and is cast using a trough, and after cooling, the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy ingot is obtained.

[0022] The yield of the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy ingot produced in the embodiment is 9960 kg, and the content in terms of mass percentage includes 11.2% of aluminum, 2.3% of magnesium, 0.12% of nickel, 0.07% of boron, 0.08% of titanium, and 0.09% of rare earth elements, and the balance is zinc.

[0023] The process of the embodiment has no open flame operation, high safety, and the magnesium is basically not burned, with a burning loss rate as low as 2.18%. Through detection, the metal entrainment rate of the embodiment is: aluminum 3.91%, zinc 72.19%, and no magnesium metal is detected, and the metal direct recovery rate is 98%.

[0024] Comparative Example The amount and mass percentage of the alloy raw material added in the comparative example are as follows: The core induction furnace used in the comparative example has a power of 45t / 720KW, and the coreless induction furnace has a power of 10t / 600KW.

[0025] The steps of producing the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy ingot in the comparative example are different from those in the embodiment in that the main component of the slag former used in the comparative example is ammonium chloride, and the aluminum ingot is added into the melting at one time.

[0026] The comparative example produces a zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy plate, including the following steps: S1: using a pusher to add zinc sheets into the core induction furnace at a rate of 250 kg / time, melting at 520°C, and adding 4.2 kg of ammonium chloride to form slag, and then transferring the molten zinc liquid into the coreless induction furnace through a trough as the base furnace for the subsequent steps; S2: adding aluminum ingots into the coreless induction furnace at one time, controlling the temperature at 750°C, and melting the first batch of aluminum ingots completely, then adding the second batch of aluminum ingots until completely melted; S3: after the aluminum is completely melted, add zinc-nickel alloy into the furnace, control the temperature at 820°C, and completely melt it by electromagnetic stirring; S4: keep the temperature at 820°C, then add sponge titanium into the furnace, and completely melt it by electromagnetic stirring; S5: reduce the temperature to 670°C, then add rare earth lanthanum-cerium alloy, and completely melt it by electromagnetic stirring; S6: keep the temperature at 670°C, then add boron powder into the furnace, and completely melt it by electromagnetic stirring; S7: finally, add magnesium ingots into the furnace, still stirring at the temperature of 670°C, until completely melted, and finally form an alloy liquid with uniform composition; S8: take 6 kg of ammonium chloride into the coreless induction furnace, fully stir to form slag to obtain powder-shaped alloy slag, and finally use a robot to salvage the powder-shaped alloy slag into a slag box to complete the slag cleaning process; S9: sample and analyze the alloy melt after slag cleaning, confirm that the content is qualified, then pour out the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy liquid from the coreless induction furnace, use a trough for casting, and obtain a zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy ingot after cooling.

[0027] The zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy ingot produced in this comparative example yielded 10290 kg. The contents, by mass percentage, included 11.35% aluminum, 2.29% magnesium, 0.12% nickel, 0.07% boron, 0.08% titanium, 0.09% rare earth elements, with the balance being zinc.

[0028] In this comparative example process, a large amount of magnesium ingots floated on the liquid surface and burned extensively, resulting in low equipment safety and a magnesium burn-off rate of 12.25%. Testing revealed the following metal entrainment rates in this comparative example: aluminum 8.14%, zinc 76.70%, with no detected magnesium entrainment, and a direct metal recovery rate of 89%.

Claims

1. A method for producing a zinc-aluminum-magnesium-nickel-titanium-boron rare earth alloy, characterized in that, Includes the following steps: S1: The zinc sheet is added to the No. 1 electric furnace using a pusher and stirred and melted at 500-550℃. Ammonium chloride is added to form slag, and then the molten zinc liquid is transferred to the No. 2 electric furnace through a chute. S2: Divide the aluminum ingots into two batches according to their weight, and add them into the No. 2 electric furnace in sequence. Control the temperature at 700-800℃, stir to aid melting. After the first batch of aluminum ingots has completely melted, add the second batch of aluminum ingots until they are completely melted. S3: After the aluminum is completely melted, add the zinc-nickel alloy into the No. 2 electric furnace, control the temperature at 800-850℃, and stir to make it completely melted; S4: Keep the temperature at 800-850℃, add the sponge titanium to the No. 2 electric furnace, and stir until it is completely melted; S5: Reduce the temperature to 650-700℃, add the rare earth lanthanum-cerium alloy into electric furnace No. 2, and stir until it is completely melted; S6: Keep the temperature at 650-700℃, add boron powder to electric furnace No. 2, and stir until it is completely melted; S7: Add the magnesium ingots to the No. 2 electric furnace and stir at a temperature of 650-700℃ until they are completely melted, eventually forming a homogeneous alloy liquid. S8: Add the slag-forming agent to the No. 2 electric furnace, then add starch on the surface, ignite the starch, stir thoroughly to form powdered alloy slag, and scoop the powdered alloy slag into the slag box to complete the slag cleaning. S9: After slag removal, the alloy melt is sampled and analyzed. Once the content is confirmed to be qualified, the No. 2 electric furnace is tilted to pour out the zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy liquid. The liquid is then cast using a chute and cooled to obtain zinc-aluminum-magnesium-nickel-titanium-boron-rare earth alloy ingots.

2. The method according to claim 1, characterized in that: The feeder in S1 adds zinc sheets to the No. 1 electric furnace at a rate of 200-300 kg / batch, and the amount of ammonium chloride added is 3-5 kg / 10 tons of zinc sheets.

3. The method according to claim 1, characterized in that: The zinc-nickel alloy described in S3 comprises, by mass percentage, 0.9%-1.1% nickel, with the balance being zinc.

4. The method according to claim 1, characterized in that: The sponge titanium described in S4, by mass percentage, comprises 99.1%-99.7% titanium, with the balance being iron, silicon, chlorine, carbon, nitrogen, oxygen, manganese, magnesium, hydrogen, nickel, and chromium.

5. The method according to claim 1, characterized in that: The rare earth lanthanum-cerium alloy described in S5 comprises 63%-67% cerium by mass percentage, with the balance being lanthanum.

6. The method according to claim 1, characterized in that: The slag-forming agent described in S8 mainly includes cryolite powder, zinc chloride, magnesium chloride, and sodium chloride, and the weight ratio of cryolite powder, zinc chloride, magnesium chloride, and sodium chloride is 40-45 : 35-40 : 5-10 : 10-15. The amount of slag-forming agent added is 5-8 kg / 10 tons of alloy liquid, and the amount of starch added is 5 kg / 10 tons of alloy liquid.

7. The method according to claim 1, characterized in that: The No. 1 electric furnace mentioned in S1 is a cored induction furnace, and the No. 2 electric furnace mentioned in S1 to S9 is a coreless induction furnace.

8. The method according to claim 1, characterized in that: The stirring method described in S1 to S8 is electromagnetic stirring.

9. The method according to claim 1, characterized in that: The zinc-aluminum-magnesium-nickel-titanium-boron rare earth alloy described in S9, by mass percentage, comprises 10%-12% aluminum, 2%-3% magnesium, 0.1%-0.2% nickel, 0.05%-0.1% boron, 0.08%-0.1% titanium, 0.08%-0.1% rare earth elements, with the balance being zinc.

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