Master alloy containing zirconium and magnesium and its production method and use

Abstract

The present invention discloses a master alloy containing zirconium and magnesium, and a production method and use thereof. The production method comprises the following steps: in the presence of a protective gas, magnesium and metal RE are formed into a rare earth-magnesium alloy liquid; in the presence of a protective gas, chloride particles are reacted with the rare earth-magnesium alloy liquid to obtain a master alloy containing zirconium and magnesium. The production method of the present invention can effectively reduce the particle size of zirconium particles in the master alloy.

Description

Technical Field

[0001] The invention relates to a master alloy containing zirconium and magnesium, and a production method and application thereof. Background Art

[0002] Magnesium alloys have excellent properties and have been widely used in various fields. Studies have found that adding zirconium to magnesium alloys can refine the grains of magnesium alloys. During the crystallization of magnesium alloys, zirconium particles are preferentially precipitated. Since zirconium particles have the same close-packed hexagonal lattice structure and similar lattice constants as magnesium, they can serve as the core of heterogeneous nucleation during alloy crystallization, thereby effectively refining the alloy's casting structure and improving the uniformity of the structure and the stability of the performance.

[0003] CN114182130A discloses a refining agent for magnesium alloy. The refining agent comprises the following components in mass ratio: CaCl2 15-40%, BaCl2 13-25%, NaCl 0-10%, CaF2 1-10%, Ti / Zr powder 0-6%, K2TiF6 / K2ZrF6 0-10%, and KCl balance. The composition contains a large amount of salt components and is used as a refining agent without forming an intermediate alloy.

[0004] CN108048718A discloses a method for producing a magnesium-zirconium master alloy. In a mixed gas composed of CO2 and SF6, zirconium chloride is added stepwise to molten metal magnesium to obtain a magnesium-zirconium master alloy. The method aims to solve the problem of uneven zirconium distribution in the magnesium-zirconium master alloy. The zirconium particles in the obtained magnesium-zirconium master alloy have a large particle size. When the zirconium particles are added to the molten magnesium as a master alloy, they will settle to the bottom of the molten magnesium, which is not conducive to improving the use efficiency of zirconium. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a method for producing a master alloy containing zirconium and magnesium. The production method can effectively reduce the particle size of zirconium particles in the master alloy. Further, the method can reduce the salt content in the master alloy.

[0006] Another object of the present invention is to provide a master alloy containing zirconium and magnesium.

[0007] Another object of the present invention is to provide a use of a master alloy containing zirconium and magnesium.

[0008] The above purpose is achieved through the following technical solutions.

[0009] In one aspect, the present invention provides a method for producing a master alloy containing zirconium and magnesium, comprising the following steps:

[0010] In the presence of a protective gas, magnesium and metal RE are formed into a rare earth-magnesium alloy liquid; in the presence of a protective gas, chloride particles are reacted with the rare earth-magnesium alloy liquid to obtain an intermediate alloy containing zirconium and magnesium;

[0011] Wherein, the chloride particles contain the following components:

[0012] Zirconium chloride 20~80wt%

[0013] Potassium chloride 10-40wt%, and

[0014] Sodium chloride 10-40wt%;

[0015] Wherein, the metal RE is selected from one or more of lanthanum, cerium, praseodymium or neodymium.

[0016] According to the production method of the present invention, preferably, the chloride particles are obtained by melting, pouring and crushing a mixture of zirconium chloride, potassium chloride and sodium chloride.

[0017] According to the production method of the present invention, preferably, the particle size of the chloride particles is 0.1-0.5 mm.

[0018] According to the production method of the present invention, preferably, the protective gas comprises an inert gas and SF6 in a volume ratio of (15-25):1.

[0019] According to the production method of the present invention, preferably, the amount of magnesium used is 50 to 150 parts by weight, the amount of metal RE used is 14 to 35 parts by weight, and the amount of chloride particles used is 75 to 250 parts by weight.

[0020] According to the production method of the present invention, preferably, metal RE is added to the stirred molten magnesium; after the metal RE is completely added to the molten magnesium, stirring is continued for 10 to 120 minutes to obtain a rare earth-magnesium alloy liquid;

[0021] Wherein, the rotation speed of the stirring device for stirring the molten magnesium is 100-300r / min.

[0022] According to the production method of the present invention, preferably, the chloride particles are added to the stirred rare earth-magnesium alloy liquid to react for 30 to 150 minutes; wherein the rotation speed of the stirring device for stirring the rare earth-magnesium alloy liquid is 100 to 300 r / min.

[0023] According to the production method of the present invention, preferably, it also includes the step of refining the reaction product obtained by the reaction of the chloride particles and the rare earth-magnesium alloy liquid with an inert gas.

[0024] In another aspect, the present invention provides a master alloy containing zirconium and magnesium, which is obtained by the above production method.

[0025] In another aspect, the present invention provides use of the above-mentioned master alloy containing zirconium and magnesium in preparing a magnesium alloy.

[0026] The production method of the present invention can reduce the particle size of zirconium particles in the master alloy. When the master alloy of the present invention is used in the preparation process of magnesium alloy, the sedimentation speed of zirconium particles in magnesium melt is slow, which can improve the utilization rate of zirconium. DETAILED DESCRIPTION

[0027] The present invention is further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0028] <Method for producing a master alloy containing zirconium and magnesium>

[0029] The master alloy of the present invention contains zirconium and magnesium. The production method of the master alloy of the present invention comprises the following steps: in the presence of a protective gas, magnesium and metal RE are formed into a rare earth-magnesium alloy liquid; in the presence of a protective gas, chloride particles are reacted with the rare earth-magnesium alloy liquid to obtain a master alloy containing zirconium and magnesium. The following is a detailed introduction.

[0030] The shielding gas of the present invention contains an inert gas and SF6. In certain embodiments, the shielding gas consists of an inert gas and SF6. The inert gas is selected from one or more of helium, neon, argon, krypton and xenon. Preferably, the inert gas is selected from one or more of helium, neon or argon. More preferably, the inert gas is argon.

[0031] The volume ratio of the inert gas to SF6 may be (15-25):1; preferably (17-22):1; and more preferably (19-20):1.

[0032] According to one embodiment of the present invention, a protective gas is introduced into the reaction device so that the reaction system reacts in a protective gas atmosphere. The reaction device may be a furnace. The flow rate of the protective gas introduced into the reaction device may be 5 to 40 mL / min; preferably 10 to 30 mL / min; more preferably 15 to 20 mL / min.

[0033] The amount of magnesium used may be 50 to 150 parts by weight, preferably 70 to 130 parts by weight, and more preferably 75 to 105 parts by weight.

[0034] Magnesium can be used in the form of molten magnesium. The temperature of the molten magnesium can be 650-830°C, preferably 700-800°C, and more preferably 740-780°C. This can not only allow the molten magnesium to fully react with the metal RE, but also reduce the volatilization of the raw materials, thereby improving the yield and safety.

[0035] The metal RE is selected from one or more of lanthanum, cerium, praseodymium or neodymium. The metal RE can be a single metal or an alloy. In some embodiments, the metal RE is selected from one of lanthanum, cerium or neodymium. In other embodiments, the metal RE is a lanthanum-cerium alloy. The mass ratio of lanthanum element to cerium element in the lanthanum-cerium alloy can be (0.5-2.5):1; preferably (1-2):1; more preferably (1.25-1.75):1.

[0036] The amount of metal RE used may be 14 to 35 parts by weight, preferably 16 to 30 parts by weight, and more preferably 20 to 27 parts by weight.

[0037] In certain embodiments, metal RE is added to molten magnesium to obtain a rare earth-magnesium alloy liquid. Preferably, metal RE is added to the molten magnesium being stirred. The rotation speed of the stirring device for stirring the molten magnesium can be 100 to 300 r / min; preferably 150 to 200 r / min. According to one embodiment of the present invention, after the metal RE is completely added to the molten magnesium, stirring is continued for 10 to 120 minutes to obtain a rare earth-magnesium alloy liquid. Preferably, the stirring is continued for 20 to 100 minutes; more preferably, the stirring is continued for 30 to 60 minutes.

[0038] The chloride particles of the present invention comprise the following components: zirconium chloride, potassium chloride and sodium chloride. In certain embodiments, the chloride particles consist of zirconium chloride, potassium chloride and sodium chloride. This can reduce the particle size of zirconium particles in the master alloy.

[0039] The content of zirconium chloride is 20 to 80 wt %, preferably 30 to 70 wt %, and more preferably 35 to 60 wt %.

[0040] The content of potassium chloride is 10-40wt%, preferably 20-30wt%, and more preferably 18-26wt%.

[0041] The content of sodium chloride is 10 to 40 wt %, preferably 20 to 30 wt %, and more preferably 18 to 26 wt %.

[0042] By controlling the contents of zirconium chloride, potassium chloride and sodium chloride within the above ranges, the particle size of zirconium particles in the master alloy can be reduced.

[0043] The present invention does not limit the shape of the chloride particles. The chloride particles can be round, triangular, rectangular, cylindrical or irregular in shape. The particle size of the chloride particles can be 0.1 to 0.5 mm, preferably 0.15 to 0.4 mm, and more preferably 0.15 to 0.3 mm. This can reduce the particle size of the zirconium particles in the master alloy.

[0044] The chloride particles of the present invention can be obtained by melting, pouring and crushing a mixture of zirconium chloride, potassium chloride and sodium chloride. Preferably, the mixture consists of zirconium chloride, potassium chloride and sodium chloride. This can reduce the particle size of the zirconium particles in the master alloy.

[0045] The amount of the chloride particles used may be 75 to 250 parts by weight, preferably 85 to 220 parts by weight, more preferably 100 to 160 parts by weight, and most preferably 100 to 140 parts by weight.

[0046] In some embodiments, the chloride particles are added to the rare earth-magnesium alloy liquid for reaction. Preferably, the chloride particles are added to the stirred rare earth-magnesium alloy liquid for reaction. In this process, the rare earth element in the rare earth-magnesium alloy liquid undergoes a reduction reaction with zirconium chloride to form zirconium and rare earth chloride.

[0047] The reaction time may be 30 to 150 min, preferably 40 to 120 min, and more preferably 50 to 100 min.

[0048] The rotation speed of the stirring device for stirring the rare earth-magnesium alloy liquid can be 100 to 300 r / min, preferably 120 to 260 r / min, and more preferably 150 to 220 r / min.

[0049] In some embodiments, the step of refining the reaction product obtained by reacting the chloride particles with the rare earth-magnesium alloy liquid with an inert gas is also included. The inert gas is selected from one or more of helium, neon, argon, krypton and xenon. Preferably, the inert gas is selected from one or more of helium, neon or argon. According to one embodiment of the present invention, the inert gas is argon.

[0050] Specifically, the reaction product is subjected to suspension blowing refining by using an inert gas, and then the floating impurities on the surface of the reaction product are removed to obtain an intermediate alloy liquid. The intermediate alloy liquid is poured to obtain an intermediate alloy containing zirconium and magnesium.

[0051] The flow rate of the inert gas may be 2 to 40 mL / min, preferably 5 to 30 mL / min, and more preferably 10 to 20 mL / min.

[0052] The refining time may be 5 to 60 min, preferably 10 to 40 min, and more preferably 20 to 30 min.

[0053] <Master alloy containing zirconium and magnesium>

[0054] The intermediate alloy containing zirconium and magnesium of the present invention is obtained by the above production method. The average particle size of the zirconium particles in the intermediate alloy containing zirconium and magnesium is less than or equal to 900nm; preferably, less than or equal to 800nm; more preferably, less than or equal to 600nm. In some embodiments, the average particle size of the zirconium particles is 550-600nm.

[0055] The content of chloride ions in the master alloy containing zirconium and coal is less than or equal to 150 ppm, preferably less than or equal to 110 ppm, and more preferably less than or equal to 100 ppm. In some embodiments, the content of chloride ions is 85-110 ppm.

[0056] <Application of Master Alloys Containing Zirconium and Magnesium>

[0057] The master alloy containing zirconium and magnesium of the present invention can be used as a master alloy in the process of manufacturing magnesium alloys, and can play a role in refining the grains of magnesium alloys. Therefore, the present invention provides the use of the master alloy containing zirconium and magnesium in the preparation of magnesium alloys. Preferably, the master alloy containing zirconium and magnesium of the present invention is used as a grain refiner for magnesium alloys.

[0058] Preparation Examples 1 to 3

[0059] A mixture of zirconium chloride, potassium chloride and sodium chloride is provided, the mixture is melted to obtain a molten mixture, the molten mixture is poured, and then crushed to obtain chloride particles with a particle size of 0.15 mm.

[0060] The contents of zirconium chloride, potassium chloride and sodium chloride in the mixture are specifically shown in Table 1.

[0061] Table 1

[0062] Zirconium chloride (wt%) Potassium chloride (wt%) Sodium chloride (wt%) Preparation Example 1 50 25 25 Preparation Example 2 60 20 20 Preparation Example 3 40 30 30

[0063] Embodiments 1 to 4

[0064] A protective gas consisting of argon and SF6 in a volume ratio of 19:1 was introduced into the reaction equipment (furnace) at a flow rate of 15 mL / min.

[0065] The metal RE is added into the stirred molten magnesium, and the rotation speed of the stirring device for stirring the molten magnesium is 150r / min; after the metal RE is completely added into the molten magnesium, the molten magnesium is continued to be stirred for t1 time to obtain a rare earth-magnesium alloy liquid.

[0066] Chloride particles are added into the stirred rare earth-magnesium alloy liquid to react and obtain a reaction product.

[0067] The reaction product is subjected to suspension blowing refining by using argon gas, and then the floating impurities on the surface of the reaction product are removed to obtain the intermediate alloy liquid. The intermediate alloy liquid is poured to obtain the intermediate alloy.

[0068] The specific method for detecting the average particle size of zirconium particles in the master alloy is as follows:

[0069] A high-resolution field emission scanning electron microscope was used to observe and analyze the polished alloy sample. The particle size of zirconium particles was calibrated through the EDS spectrum and the electron microscope ruler function. At the same time, the software ImagePro was used to complete the statistical analysis of the particle size of zirconium particles in the scanning electron microscope image area to obtain the average particle size data.

[0070] Glow discharge mass spectrometry (GDMS) was used to detect the chloride ion content in the master alloy.

[0071] The specific parameters are shown in Table 2. The average particle size of zirconium particles and the content of chloride ions are shown in Table 2.

[0072] Table 2

[0073]

[0074] Note: In the lanthanum-cerium alloy, the mass ratio of lanthanum to cerium is 0.75:0.5.

[0075] The present invention is not limited to the above-mentioned embodiments. Without departing from the essential content of the present invention, any deformation, improvement and substitution that can be thought of by those skilled in the art shall fall within the scope of the present invention.

Claims

1. A method for producing a master alloy containing zirconium and magnesium, characterized in that: The steps include: In the presence of a protective gas, adding metal RE to the stirred molten magnesium; after the metal RE is completely added to the molten magnesium, continuing stirring for 10 to 120 minutes to obtain a rare earth-magnesium alloy liquid; the speed of the stirring device for stirring the molten magnesium is 100 to 300 r / min; In the presence of protective gas, adding chloride particles to the stirred rare earth-magnesium alloy liquid to react for 30 to 150 minutes to obtain an intermediate alloy containing zirconium and magnesium; the speed of the stirring device for stirring the rare earth-magnesium alloy liquid is 100 to 300 r / min; The amount of magnesium is 75 to 105 parts by weight, the amount of metal RE is 14 to 35 parts by weight, and the amount of chloride particles is 100 to 140 parts by weight; Wherein, the chloride particles contain the following components: Zirconium chloride 35~60wt%, Potassium chloride 10-40wt%, and Sodium chloride 10-40wt%; The chloride particles are obtained by melting, pouring and crushing a mixture of zirconium chloride, potassium chloride and sodium chloride; The particle size of the chloride particles is 0.1 to 0.5 mm; Wherein, the metal RE is selected from one or more of lanthanum, cerium, praseodymium or neodymium; The protective gas is composed of an inert gas and SF6 in a volume ratio of (15-25):1; The average particle size of zirconium particles in the intermediate alloy containing zirconium and magnesium is less than or equal to 600 nm, and the content of chloride ions is less than or equal to 110 ppm.

2. The production method according to claim 1, characterized in that The particle size of the chloride particles is 0.15-0.4 mm.

3. The production method according to claim 1, characterized in that The amount of metal RE used is 16 to 30 parts by weight.

4. The production method according to claim 1, characterized in that The method also includes the step of using an inert gas to refine the reaction product obtained by the reaction of chloride particles and rare earth-magnesium alloy liquid.

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