Production method of vanadium-aluminum alloy

Abstract

The invention provides a production method of a vanadium-aluminum alloy. The production method comprises the following steps: treating raw materials; the high-purity calcium fluoride is dried; lime and water are mixed according to the proportion of 1: 1, and the mixture is put into a drying box to be dried; the preparation method comprises the following steps: proportioning the following raw materials: vanadium pentoxide, aluminum powder and calcium fluoride according to the ratio of 1: (0.58-0.68): (0.02-0.13), proportioning the calcium fluoride according to the unit reaction heat of 3100-3150 KJ / kg, and uniformly mixing; filling the mixture into a reaction furnace body, compacting, and spreading an ignition agent on the material; ignition reaction; after the reaction is finished, standing the furnace body for 24 hours, moving out the furnace body, naturally cooling for 48 hours, and discharging from the furnace; the method mainly solves the problems of high alloy carbon content caused by graphite falling of the alloy graphite crucible and oxidation film and nitride film phenomena caused by metal solidification cracks.

Description

Technical Field

[0001] The present invention relates to the technical field of alloy preparation, in particular to a production method of vanadium-aluminum alloy. Background Art

[0002] Vanadium-aluminum alloys are primarily used in titanium alloys, primarily TC4 titanium alloys. With excellent corrosion resistance, high-temperature strength, and ductility, vanadium-aluminum alloys are widely used in aerospace, automotive, and electronic equipment. One of the largest applications of vanadium-aluminum alloys is as master alloys for vanadium-containing titanium alloys. The addition of vanadium metal refines the grain size and improves the ductility of the titanium alloy, facilitating the molding of complex aerospace components. The carbon content in the alloy can easily lead to the formation of refractory vanadium carbides, affecting product quality. The oxide film on the alloy surface is one of the main factors contributing to high oxygen content. This oxide film is difficult to remove during subsequent processing, remaining in the final product and negatively impacting product quality. Therefore, the oxide film is a major quality defect in the production of vanadium-aluminum master alloys.

[0003] 55V aluminum is primarily used in the titanium alloy industry as an additive. Most existing 55V aluminum alloys are produced using the aluminothermic process, with a smaller portion produced using a two-step process involving aluminothermic furnaces and vacuum induction furnaces. During the cooling and solidification process after the reaction, cracks easily form in the alloy. These cracks absorb oxygen and nitrogen, causing oxide and nitride films to form on the cracked surfaces, leading to product defects. Summary of the Invention

[0004] In view of the above defects, the present invention proposes a method for producing vanadium-aluminum alloy, comprising the following steps: Raw material processing: Grind the vanadium pentoxide flakes to a suitable particle size of 0-3mm using a Raymond mill and dry at 200 degrees; Drying high-purity calcium fluoride; Graphite furnace body treatment: Mix lime and water in a ratio of 1:1, leave it for 1 day, stir it evenly, and then apply it on the inner wall of the graphite crucible, and then put it in a drying oven to dry; The following raw materials are prepared: vanadium pentoxide: aluminum powder: calcium fluoride: = 1: 0.58-0.68: 0.02-0.13, and the calcium fluoride is prepared in a ratio according to a unit reaction heat of 3100-3150 kJ / kg, and mixed evenly; The mixed material is loaded into the reactor body, compacted, and ignition agent is spread on the material; ignition reaction; After the reaction is completed, the furnace body is kept still for 24 hours, then removed and allowed to cool naturally for 48 hours before being taken out of the furnace.

[0005] Furthermore, the composition of the raw material vanadium pentoxide is: V2O5: 98.53%, P: 0.0005%, Si: 0.0039%, C: 0.003%, S: 0.0024%, Si: 0.008%, Fe: 0.010%.

[0006] Furthermore, the aluminum powder has a composition of Al: 99.32%, Fe: 0.085%, Cu: 0.0041%, and Si: 0.038%.

[0007] Furthermore, the vanadium-aluminum alloy produced by the production method of the vanadium-aluminum alloy has an alloy composition of V: ​​59.01%, Si: 0.095%, C<0.032%, O<0.025%, N<0.004%, Fe: 0.14%, and the balance is aluminum.

[0008] The invention mainly solves the problems of high carbon content in alloy caused by graphite shedding of alloy graphite crucible and oxide film and nitride film caused by metal solidification cracks. DETAILED DESCRIPTION

[0009] A method for producing a vanadium-aluminum alloy, characterized by comprising the following steps: Raw material processing: Grind the vanadium pentoxide flakes to a suitable particle size of 0-3mm using a Raymond mill and dry at 200 degrees; Drying high-purity calcium fluoride; Graphite furnace body treatment: Mix lime and water in a ratio of 1:1, leave it for 1 day, stir it evenly, and then apply it on the inner wall of the graphite crucible, and then put it in a drying oven to dry; The following raw materials are prepared: vanadium pentoxide: aluminum powder: calcium fluoride: = 1: 0.58-0.68: 0.02-0.13, and the calcium fluoride is prepared in a ratio according to a unit reaction heat of 3100-3150 kJ / kg, and mixed evenly; Since the higher the melting point, the higher the solidification point, for example, the melting point of slag is about 2000 degrees. Below 2000 degrees, it will be semi-solidified, while the melting point of the metal below is about 1600 degrees. The alloy is still liquid, and the slag solidifies before the alloy.

[0010] Similarly, in the original design, due to the high melting point of calcium oxide (2572°C), it formed a high-melting-point slag together with the aluminum oxide produced by the reaction (melting point 2054°C). Due to different melting points and surface tensions, the slag and the underlying alloy liquid separated in the later stages of the reaction. Due to its high melting point, the slag solidified quickly. As the slag cooled, the alloy liquid below it had not yet solidified. The solidified slag layer would shrink, resulting in the slag layer not fully covering the alloy liquid surface, forming a primary gap between the slag layer and the alloy liquid surface. During the cooling and solidification process after the reaction ended, as the alloy liquid solidified, a secondary crack appeared extending into the alloy along the solidification direction. This allowed external oxygen and nitrogen to enter the secondary crack along the primary gap, causing the secondary crack to absorb oxygen and nitrogen, resulting in oxide and nitride films on the cracked alloy surface, leading to overall product defects, especially high nitrogen and oxygen content.

[0011] In this solution, the melting point of calcium fluoride is 1402°C, which is much lower than that of calcium oxide. Calcium fluoride is added as a coolant and mixed with alumina to lower the melting point of the slag layer of the mixture, shortening the smelting gap with the alloy liquid. The condensation speed of the slag layer is close to that of the alloy liquid, and they solidify almost synchronously, avoiding the first gap and the second crack. This also prevents oxygen and nitrogen from entering the alloy along the gap, avoiding the increase in oxygen and nitrogen content, and achieving the technical effect of reducing oxygen and nitrogen content.

[0012] The mixed material is loaded into the reactor body, compacted, and ignition agent is spread on the material; ignition reaction; After the reaction is completed, the furnace body is kept still for 24 hours, then removed and allowed to cool naturally for 48 hours before being taken out of the furnace.

[0013] Furthermore, the composition of the raw material vanadium pentoxide is: V2O5: 98.53%, P: 0.0005%, Si: 0.0039%, C: 0.003%, S: 0.0024%, Si: 0.008%, Fe: 0.010%.

[0014] Furthermore, the aluminum powder has a composition of Al: 99.32%, Fe: 0.085%, Cu: 0.0041%, and Si: 0.038%.

[0015] Furthermore, the vanadium-aluminum alloy produced by the vanadium-aluminum alloy production method has an alloy composition of V: ​​59.01%, Si: 0.095%, C<0.032%, O<0.025%, N<0.004%, Fe: 0.14%, and the balance is aluminum.

[0016] The above describes the embodiments of the present invention in detail, but the present invention is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the relevant technical field without departing from the purpose of this patent.

Claims

1. A method for producing vanadium aluminum alloy, characterized in that The following steps are involved: Raw material processing: Grind the vanadium pentoxide flakes to a suitable particle size of 0-3mm using a Raymond mill and dry at 200 degrees; Drying high-purity calcium fluoride; Graphite furnace body treatment: Mix lime and water in a ratio of 1:1, leave it for 1 day, stir it evenly, and then apply it on the inner wall of the graphite crucible, and then put it in a drying oven to dry; The following raw materials are prepared: vanadium pentoxide: aluminum powder: calcium fluoride: = 1: 0.58-0.68: 0.02-0.13, and the calcium fluoride is prepared in a ratio according to a unit reaction heat of 3100-3150 kJ / kg, and mixed evenly; The mixed material is loaded into the reactor body, compacted, and ignition agent is spread on the material; ignition reaction; After the reaction is completed, the furnace body is kept still for 24 hours, then removed and allowed to cool naturally for 48 hours before being taken out of the furnace.

2. The method for producing a vanadium aluminum alloy according to claim 1, wherein: The composition of the raw material vanadium pentoxide is: V2O5: 98.53%, P: 0.0005%, Si: 0.0039%, C: 0.003%, S: 0.0024%, Si: 0.008%, and Fe: 0.010%.

3. The method for producing a vanadium aluminum alloy according to claim 1, wherein: The aluminum powder comprises: Al: 99.32%, Fe: 0.085%, Cu: 0.0041%, and Si: 0.038%.

4. The vanadium-aluminum alloy produced by the method for producing the vanadium-aluminum alloy according to any one of claims 1 to 3, characterized in that: The alloy composition is V: 59.01%, Si: 0.095%, C<0.032%, O<0.025%, N<0.004%, Fe: 0.14%, and the balance is aluminum.