Method for preparing high-cleanliness and high-content TiB2 aluminum-based composite material through in-situ generation

Abstract

The invention provides a method for preparing a high-cleanliness and high-content TiB2 aluminum-based composite material through in-situ generation, which comprises the following steps: adding a mixture of potassium fluotitanate and potassium fluoborate into molten aluminum by using an electric induction furnace, directly generating a composite material containing TiB2 (with the content of 3.0-5.0%) by using an in-situ generation method, and settling TiB2 particles by using a standing method to obtain the high-cleanliness and high-content TiB2 aluminum-based composite material. And the low-content alloy on the upper layer is removed according to the proportion, and therefore the high-cleanliness and high-content TiB2 aluminum-based composite material is prepared. The wettability of TiB2 contained in the composite material produced by the process and an aluminum alloy melt interface is good, the content of K ions is lower than 0.05%, the length of oxide in any 1 cm < 2 > is lower than 500 microns, and the content of TiB2 can reach 8.0-15.0%. The invention provides the process for preparing the high-cleanliness and high-content TiB2 aluminum-based composite material by combining low-content in-situ generation and standing settlement, wherein the process is high in efficiency and stable in quality. The content of K ions in the alloy prepared through the technology is lower than 0.05%, the length of oxide in any 1 cm < 2 > is lower than 500 microns, and the content of TiB2 can reach 8.0-15.0%.

Description

Technical Field

[0001] The present invention relates to the field of TiB2 aluminum-based composite materials, and in particular to a method for in-situ generation and preparation of high-purity and high-content TiB2 aluminum-based composite materials. Background Art

[0002] TIB2 aluminum-based composites have broad application prospects in industries such as aerospace and automobile manufacturing due to their excellent properties such as high specific strength, high specific modulus, wear resistance and high temperature resistance. For a long time, research on the preparation process of aluminum-based composites has always focused on traditional methods of external reinforcement composites, such as powder metallurgy, stirring casting, and extrusion casting. These methods are not only complex and costly, but also have problems such as poor compatibility between the reinforcement and the matrix, which limits their application in industry. In-situ endogenous TiB2 reinforced aluminum-based composites have many advantages that external reinforcing phase reinforced aluminum-based composites do not have, such as fine reinforcement particles and good compatibility between endogenous particles and the matrix. The use of in-situ synthesis technology to prepare TiB2 reinforced aluminum-based composites can effectively solve the above problems. However, it is difficult to remove potassium fluoroaluminate from the alloy when preparing TiB2 composite materials in situ, especially for high-content (TiB2 content above 8.0%) TiB2 composite materials. Due to their high viscosity, it is even more difficult to remove potassium fluoroaluminate from the alloy (characterized by detecting the K ion content in the alloy). Therefore, the use of new technologies to prepare high-cleanliness and high-content TiB2 aluminum-based composite materials has become a new development direction. Summary of the Invention

[0003] In order to make up for the deficiencies of the prior art, the present invention provides a method for in-situ generation and preparation of high-purity and high-content TiB2 aluminum-based composite materials.

[0004] The present invention is achieved through the following technical solution: a method for in-situ generation of a high-cleanliness, high-content TiB2 aluminum-based composite material, specifically comprising the following steps: Step S1: adding an aluminum ingot into an induction furnace, melting it and heating it to 800-850°C; Step S2: Adjust the induction furnace to a stirring mode with a stirring power of 200 kW, add the potassium fluorotitanate and potassium fluoroborate mixture into the induction furnace, react for 30-40 minutes, and then pour out the molten salt on the surface of the alloy; Step S3, adding 3.0 kg of calcium oxide per ton of alloy to clean the remaining potassium fluoroaluminate on the alloy surface; Step S4: After cleaning, the alloy temperature is lowered to 800-830°C, and argon is passed through a rotary degasser for refining and degassing for 20-30 minutes; Step S5: After refining and degassing, clean the slag on the alloy surface, heat the alloy to 950-1000°C under argon protection, turn off the electric furnace, and let the alloy stand naturally for 2.0-3.0 hours. Then, remove the upper layer of alloy after standing according to the proportion, stir the remaining alloy evenly, and then cast it.

[0005] As a preferred solution, the amount of potassium fluorotitanate and potassium fluoroborate mixture added in step S2 is calculated based on a TiB2 content of 3-5%.

[0006] As a preferred solution, the purity of the aluminum ingot is greater than 99.85%, the purity of the potassium fluorotitanate is greater than 99.8%, and the purity of the potassium fluoroborate is greater than 99.8%.

[0007] As a preferred solution, the K ion content of the high-cleanliness and high-content TiB2 aluminum-based composite material is less than 0.05%, the oxide length in any 1cm2 is less than 500um, and the TiB2 content can reach 8.0-15.0%.

[0008] Due to the adoption of the above technical solution, the present invention has the following beneficial effects compared with the prior art: The present invention uses an induction furnace to add a mixture of potassium fluorotitanate and potassium fluoroborate to molten aluminum, and uses an in-situ generation method to directly generate a composite material containing TiB2 (content 3.0-5.0%). Then, a static method is used to settle the TiB2 particles and remove the upper low-content alloy in proportion, thereby preparing a high-cleanliness, high-content TiB2 aluminum-based composite material. The composite material produced by this process contains TiB2 with good wettability at the interface with the aluminum alloy melt, with a K ion content of less than 0.05% and any 1cm 2 The length of the medium oxide is less than 500um, and the TiB2 content can reach 8.0-15.0%.

[0009] The present invention provides a high efficiency and stable quality process for preparing high cleanliness and high content TiB2 aluminum-based composite materials by combining low content in-situ generation with static sedimentation. The K ion content of the alloy prepared by this process is less than 0.05%, and any 1cm 2 The length of the medium oxide is less than 500um, and the TiB2 content can reach 8.0-15.0%.

[0010] Additional aspects and advantages of the invention will become apparent from the description which follows, or may be learned by practice of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which: Figure 1This is an electron microscope photograph of an aluminum-based composite material with a TiB2 content of 10.0% produced by the method of the present invention; Figure 2 The present invention is an electron microscope photograph of an aluminum-based composite material with a TiB2 content of 15.0% produced by the method of the present invention. DETAILED DESCRIPTION

[0012] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0013] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0014] The following combination Figures 1 to 2 The method for in-situ preparation of high-purity and high-content TiB2 aluminum-based composite materials according to an embodiment of the present invention is described in detail.

[0015] Example 1 Preparation of aluminum-based composite materials with 8.0% TiB2 content: 1000 kg of 99.85% aluminum ingots were added to an induction furnace, melted and heated to 800°C, the furnace was converted to stirring mode with a stirring power of 200KW, 138.92 kg of potassium fluorotitanate and 145.77 kg of potassium fluoroborate were mixed evenly and added to the induction furnace. After reacting for 20 minutes, the molten salt on the surface of the alloy was poured out, and after pouring, 3.0 kg of calcium oxide was added to clean the remaining fluoride salt on the surface of the alloy; after cleaning, the alloy was cooled to 810°C and refined and degassed with argon in a rotary degasser for 20 minutes. After refining and degassing, the slag on the surface of the alloy was cleaned first, and then argon was introduced, and the alloy was heated to 950°C, the furnace was stopped and allowed to stand for 2.0 hours, and then 500 kg of the upper alloy was poured out. The remaining 500 kg of alloy was stirred evenly and then cast. The alloy prepared by this method was tested to have a TiB2 content of 8.14%, a K ion content of 0.025%, and any 1 cm 2 The maximum length of the medium oxide is 316.47um.

[0016] Example 2 Preparation of aluminum-based composite materials with 10.0% TiB2 content 1000 kg of 99.85% aluminum ingots were added to an induction furnace, melted and heated to 830°C, the furnace was converted to stirring mode with a stirring power of 200KW, 173.65 kg of potassium fluorotitanate and 182.21 kg of potassium fluoroborate were mixed evenly and added to the induction furnace. After reacting for 25 minutes, the molten salt on the surface of the alloy was poured out, and after pouring, 3.0 kg of calcium oxide was added to clean the remaining fluoride salt on the surface of the alloy; after cleaning, the alloy was cooled to 820°C and refined and degassed with argon in a rotary degasser for 25 minutes. After refining and degassing, the slag on the surface of the alloy was cleaned first, and then argon was introduced, and the alloy was heated to 980°C, the furnace was stopped and allowed to stand for 2.5 hours, and then 500 kg of the upper alloy was poured out. The remaining 500 kg of alloy was stirred evenly and then cast. The alloy prepared by this method was tested to have a TiB2 content of 10.43%, a K ion content of 0.043%, and a 1 cm 2 The maximum length of the medium oxide is 405.32um.

[0017] Example 3 Preparation of aluminum-based composite materials with 15.0% TiB2 content 1000 kg of 99.85% aluminum ingots were added to an induction furnace, melted and heated to 850°C, the furnace was converted to a stirring mode with a stirring power of 200KW, 173.65 kg of potassium fluorotitanate and 182.21 kg of potassium fluoroborate were mixed evenly and added to the induction furnace. After reacting for 30 minutes, the molten salt on the surface of the alloy was poured out, and after the pouring was completed, 3.0 kg of calcium oxide was added to clean the remaining fluoride salt on the surface of the alloy; after cleaning, the alloy was cooled to 830°C and refined and degassed with argon in a rotary degasser for 30 minutes. After refining and degassing, the slag on the surface of the alloy was cleaned first, and then argon was introduced, the alloy was heated to 1000°C, the furnace was stopped and allowed to stand for 3.0 hours, and then 666 kg of the upper alloy was poured out. The remaining 334 kg of alloy was stirred evenly and then cast. The alloy prepared by this method was tested to have a TiB2 content of 15.24%, a K ion content of 0.042%, and a 1 cm 2 The maximum length of the medium oxide is 478.67um.

[0018] Throughout this specification, terms such as "one embodiment," "some embodiments," and "specific embodiments" mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0019] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for in-situ preparation of high-purity and high-content TiB2 aluminum-based composite materials, characterized in that , specifically including the following steps: Step S1: adding an aluminum ingot into an induction furnace, melting it and heating it to 800-850°C; Step S2: Adjust the induction furnace to a stirring mode with a stirring power of 200 kW, add the potassium fluorotitanate and potassium fluoroborate mixture into the induction furnace, react for 30-40 minutes, and then pour out the molten salt on the surface of the alloy; Step S3, adding 3.0 kg of calcium oxide per ton of alloy to clean the remaining potassium fluoroaluminate on the alloy surface; Step S4: After cleaning, the alloy temperature is lowered to 800-830°C, and argon is passed through a rotary degasser for refining and degassing for 20-30 minutes; Step S5: After refining and degassing, clean the slag on the alloy surface, heat the alloy to 950-1000°C under argon protection, turn off the electric furnace, and let the alloy stand naturally for 2.0-3.0 hours. Then, remove the upper layer of alloy after standing according to the proportion, stir the remaining alloy evenly, and then cast it.

2. The method for in-situ preparation of high-purity and high-content TiB2 aluminum-based composite materials according to claim 1, characterized in that The purity of the aluminum ingot is greater than 99.85%, the purity of potassium fluorotitanate is greater than 99.8%, and the purity of potassium fluoroborate is greater than 99.8%.

3. The method for in-situ preparation of high-purity and high-content TiB2 aluminum-based composite materials according to claim 1, characterized in that The amount of potassium fluorotitanate and potassium fluoroborate mixture added in step S2 is calculated based on the TiB2 content of 3-5%.

4. The method for in-situ preparation of high-purity and high-content TiB2 aluminum-based composite materials according to claim 1, characterized in that: The K ion content of the high-cleanliness and high-content TiB2 aluminum-based composite material is less than 0.05%, and any 1cm 2 The length of the medium oxide is less than 500um, and the TiB2 content can reach 8.0-15.0%.

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