High-elongation and high-thermal-conductivity TiB2-Al-Ce-La-Fe alloy as well as preparation method and application thereof

Abstract

The invention provides a TiB2-Al-Ce-La-Fe alloy with high elongation and high thermal conductivity and a preparation method and application of the TiB2-Al-Ce-La-Fe alloy. According to the TiB2-Al-Ce-La-Fe alloy, the mass fraction of Ce is 4%-5%; the mass fraction of the Fe element is 0.3%-0.5%; the mass fraction of the element La is 1.2%-1.7%; the mass fraction of the TiB2 is 0.01%-0.1%. The preparation method of the TiB2-Al-Ce-La-Fe alloy comprises the following steps: smelting raw materials in a well type smelting resistance furnace, adding an Al-TiB2 intermediate alloy, and casting the obtained melt into a mold, so as to obtain the TiB2-Al-Ce-La-Fe alloy. The TiB2-Al-Ce-La-Fe alloy with the high elongation rate and the high thermal conductivity is good in thermal conductivity, and the thermal conductivity of the alloy ranges from 202.96 W / (m.K) to 209.27 W / (m.K); the mechanical property is excellent, and the ductility is 23.8-31%.

Description

Technical Field

[0001] The present invention relates to alloy technology, and in particular to a high-elongation, high-thermal-conductivity TiB2-Al-Ce-La-Fe alloy, and a preparation method and application thereof. Background Art

[0002] In recent years, with the rapid development of new energy vehicles and 5G communication industries, various types of equipment are developing towards integration and miniaturization, and the power density of the equipment has increased significantly, resulting in increasingly stringent heat dissipation requirements. At present, the commonly used high thermal conductivity aluminum alloys are mainly Al-Si alloys. However, the Si content in cast Al-Si alloys is usually high (generally not less than 6wt.%), which causes a large amount of lamellar eutectic Si phase to precipitate in the alloy, thereby significantly reducing the thermal conductivity, electrical conductivity and mechanical properties of the alloy. At the same time, the thermal conductivity of Al-Si alloys is low (<180W / (m·K)), which has gradually failed to meet the growing application needs. Summary of the invention

[0003] The purpose of the present invention is to propose a high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy in response to the growing application needs. The preparation method of the alloy is simple, and the raw materials are easy to obtain. The alloy has good thermal conductivity, and the alloy thermal conductivity is 202.96-209.27W / (m·K); the mechanical properties are excellent, and the elongation is 23.8-31%.

[0004] It should be noted that, in the present invention, unless otherwise specified, the specific meaning of "including" in relation to composition limitations and descriptions includes both open-ended "including", "comprising", etc. and similar meanings, as well as closed-ended "composed of", "composed of", etc. and similar meanings.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy, wherein the mass fraction of Ce is 4%-5%; the mass fraction of Fe element is 0.3%-0.5%; the mass fraction of La element is 1.2%-1.7%; and the mass fraction of TiB2 is 0.01%-0.1%.

[0006] Furthermore, in the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy, the mass fraction of Ce element is preferably 4.4-4.6%; the mass fraction of La element is preferably 1.4-1.6%; the mass fraction of Fe element is preferably 0.35-0.45%; and the mass fraction of TiB2 is preferably 0.01-0.05%.

[0007] Furthermore, in the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy, the mass fraction of the Ce element is more preferably 4.5%; the mass fraction of the La element is more preferably 1.5%; the mass fraction of the Fe element is more preferably 0.4%; and the mass fraction of TiB2 is more preferably 0.02%.

[0008] Furthermore, in the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy, titanium and boron form a TiB2 intermediate phase, which exists in the form of particles with a particle size of 200nm-1μm. In the present invention, the average size of the TiB2 particles is 227.9nm.

[0009] Furthermore, the thermal conductivity of the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy is 202.96-209.27 W / (m·K), and the elongation is 23.8-31%.

[0010] Another object of the present invention is to disclose a method for preparing a TiB2-Al-Ce-La-Fe alloy with high elongation and high thermal conductivity, comprising the following steps:

[0011] Melting: pure aluminum, Al-La, Al-Fe, and Al-Ce are placed in a graphite clay crucible, heated to 740-760°C in a pit-type melting resistance furnace, and then Al-TiB2 master alloy is added, high-purity argon is introduced for degassing, and finally an auxiliary process is performed for 3-5 minutes to obtain a melt;

[0012] Casting: When the melt is cooled to 710-730°C, it is cast into a preheated mold to obtain a high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy.

[0013] Furthermore, the purity of the pure aluminum is greater than or equal to 99.997%. Unless otherwise specified, % in the present invention refers to mass percentage.

[0014] Furthermore, the Al-La has a La content of 9.5-10.5 wt.%, preferably Al-10La, that is, an Al-La alloy having a La content of 10 wt.%.

[0015] Furthermore, the Fe content in the Al-Fe is 9.7-10.3 wt.%, preferably Al-10Fe, that is, an Al-Fe alloy with a Fe content of 10 wt.%.

[0016] Furthermore, the Ce content in the Al-Ce is 18-22 wt.%, preferably Al-20Ce, that is, an Al-Ce alloy with a Ce content of 20 wt.%.

[0017] Furthermore, the TiB2 content in the Al-TiB2 master alloy is 5.8-6.2wt.%, preferably Al-6TiB2, that is, the TiB2 content is 6wt.%.

[0018] Furthermore, the high-purity argon gas degassing time is 3-7 minutes.

[0019] Furthermore, the auxiliary process is ultrasonic treatment.

[0020] Furthermore, the preheated mold temperature is 240-260°C, preferably 250°C.

[0021] Another object of the present invention is to disclose a high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy for use in the field of 5G communication base station (AAU) casing.

[0022] The high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy of the present invention, its preparation method and use have the following advantages compared with the prior art:

[0023] 1) The thermal conductivity of the Al-Ce-La-Fe alloy proposed in the present invention can reach above 200 W / (m·K), which greatly meets the application requirements.

[0024] 2) The present invention adds TiB2 refiner to compensate for the poor mechanical properties of Al-Ce-La-Fe alloy. The added TiB2 refiner can significantly improve the mechanical properties of Al-Ce-La-Fe alloy through mechanisms such as heterogeneous nucleation and grain growth inhibition, making the elongation of the alloy as high as 23.8-31%.

[0025] 3) my country is a major rare earth country with rich rare earth reserves, among which Ce and La elements account for a large proportion. The present invention uses Ce and La elements as main doping elements, which can reduce alloy costs and further expand development prospects.

[0026] 4) The preparation method of the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy of the present invention is simple and the required raw materials are easy to obtain, which not only simplifies the production process but also reduces costs, making the commercial production of this high-performance alloy possible.

[0027] In summary, the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy of the present invention has good application prospects and large-scale promotion potential in the field of high thermal conductivity aluminum alloys. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 1 is the tensile curve of the alloy of the embodiment and the comparative example;

[0029] Figure 2Schematic diagram of mechanical properties of alloys of Example and Comparative Example;

[0030] Figure 3 Schematic diagram of thermal conductivity of alloys of examples and comparative examples. DETAILED DESCRIPTION

[0031] The present invention is further described below with reference to the examples. The description of the technical features described below is based on representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. It should be noted that:

[0032] Unless otherwise stated, the units used in this specification are all international standard units, and the numerical values ​​and numerical ranges appearing in the present invention should be understood to include the inevitable systematic errors in industrial production.

[0033] In this specification, the numerical range expressed using "a numerical value A to a numerical value B" means a range including the endpoints numerical values ​​A and B.

[0034] In the present specification, a numerical range expressed using "above" or "below" means a numerical range including the number.

[0035] In this specification, the word "may" means both performing a certain process and not performing a certain process.

[0036] In this specification, the use of "optional" or "optional" indicates that certain substances, components, execution steps, application conditions and other factors are used or not used.

[0037] In this specification, when "normal temperature" or "room temperature" is used, the temperature may be 15-25°C.

[0038] In this manual, the reagents or instruments used without indicating the manufacturer are all conventional products that can be obtained through commercial purchase.

[0039] Example 1

[0040] Examples 1-3 disclose a variety of high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloys, the elements of which are shown in Table 1. The preparation method thereof is as follows:

[0041] 1. Raw material preparation: pure Al (99.997%), Al-20Ce, Al-10La, Al-10Fe, Al-6TiB2 master alloy; Al-6TiB2 master alloy (where 1.8≤Ti / B≤2.5, Ti and B elements mainly exist in the form of intermediate phase TiB2, TiB2 exists in the form of particles, the particle size is 200nm-1μm, and the mass content of TiB2 is 6%);

[0042] 2. Melting: pure aluminum, Al-10Fe, Al-10La, Al-20Ce are placed in a crucible, placed in a resistance furnace and heated to 750°C, then Al-6TiB2 master alloy is added, and after it is completely melted, high-purity argon gas is introduced to degas the melt for 5 minutes to make it completely melted, and finally ultrasonic treatment is performed for 4 minutes to obtain a melt;

[0043] 3. Casting: After the melt is cooled to 720°C, pour the melt into a preheated mold (250°C) to obtain a high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy ingot.

[0044] Comparative Example 1

[0045] This comparative example discloses an Al-Ce-La-Fe alloy, the elements of which are shown in Table 1. The preparation method thereof is the same as that of Example 1.

[0046] Table 1 Chemical composition design of each alloy (wt.%)

[0047] Ce La Fe <![CDATA[TiB2]]> Al Comparative Example 1 4.5 1.5 0.4 0 Bal. Example 1 4.5 1.5 0.4 0.02 Bal. Example 2 4.5 1.5 0.4 0.06 Bal. Example 3 4.5 1.5 0.4 0.1 Bal.

[0048] The alloys of Examples 1-3 and Comparative Example 1 were tested respectively, and the test results are as follows:

[0049] Figure 1 and Figure 2 The tensile curves and mechanical properties diagrams of each alloy are shown in Figure 2. Figure 1 It can be seen that with the increase of TiB2 particles, the strength and elongation of the alloy increase. After adding 0.02wt.% of particles, the elongation reaches the highest, reaching 31%.

[0050] Figure 3 It is a schematic diagram of the thermal conductivity of each alloy. It can be seen from the figure that after adding particles, although the thermal conductivity of the alloy is reduced, the minimum can be maintained above 200W / (m·K).

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy, characterized in that: The mass fraction of Ce is 4%-5%; the mass fraction of Fe element is 0.3%-0.5%; the mass fraction of La element is 1.2%-1.7%; and the mass fraction of TiB2 is 0.01%-0.1%.

2. The high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to claim 1, characterized in that: Titanium and boron form a TiB2 intermediate phase.

3. The high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to claim 2, characterized in that: The TiB2 intermediate phase exists in the form of particles, and the particle size thereof is 200nm-1μm.

4. The high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to claim 1, characterized in that: Its thermal conductivity is 202.96-209.27 W / (m·K) and its elongation is 23.8-31%.

5. A method for preparing the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to any one of claims 1 to 4, characterized in that: The following steps are involved: Melting: pure aluminum, Al-La, Al-Fe, and Al-Ce are placed in a graphite clay crucible, heated to 740-760°C in a pit-type melting resistance furnace, and then Al-TiB2 master alloy is added, high-purity argon is introduced for degassing, and finally an auxiliary process is performed for 3-5 minutes to obtain a melt; Casting: When the melt is cooled to 710-730°C, it is cast into a preheated mold to obtain a high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy.

6. The method for preparing the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to claim 5, characterized in that: The purity of the pure aluminum is greater than or equal to 99.997%.

7. The method for preparing the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to claim 5, characterized in that: The La content in the Al-La is 9.5 to 10.5 wt.% And / or, the Fe content in the Al-Fe is 9.7-10.3wt.%; And / or, the Ce content in the Al-Ce is 18-22 wt.%; And / or, the TiB2 content in the Al-TiB2 master alloy is 5.8-6.2wt.%.

8. The method for preparing the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to claim 5, characterized in that: The high-purity argon gas degassing time is 3-7 minutes.

9. The method for preparing the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to claim 5, characterized in that: The auxiliary process is ultrasonic treatment.

10. Use of the high elongation and high thermal conductivity TiB2-Al-Ce-La-Fe alloy according to any one of claims 1 to 4 in the field of 5G communication base station casing.

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