AlNbB alloy target material and preparation method thereof
By combining spark plasma pre-sintering and hot isostatic pressing processes, the problems of low density and uneven composition of AlNbB alloy targets were solved, and efficient and low-energy consumption alloy target preparation was achieved with a high product qualification rate.
Patent Information
- Application Number
- CN202510871910.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-26
- Publication Date
- 2025-09-16
AI Technical Summary
In the prior art, the preparation process of AlNbB alloy targets suffers from high-temperature smelting energy consumption, difficulty in controlling alloy composition, and low density of targets prepared by hot isostatic pressing, which affects coating performance.
A process combining spark plasma pre-sintering and hot isostatic pressing is adopted. Al powder, Nb powder and B powder are first mixed and then spark plasma pre-sintered, followed by degassing and hot isostatic pressing. The temperature and pressure of sintering and hot isostatic pressing are controlled to ensure the densification of the alloy powder.
The highly efficient preparation of AlNbB alloy targets has been achieved, with a relative density of over 98%, uniform element distribution, no segregation, high production efficiency and low energy consumption.
Smart Images
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Figure HDA0005470071590000011
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of powder metallurgy, and in particular to an AlNbB alloy target and a preparation method thereof. Background Art
[0002] AlNbB coatings offer excellent oxidation and corrosion resistance and are widely used in semiconductors, new energy batteries, and other fields. Al forms a dense oxide film at high temperatures, hindering the oxidation reaction from progressing into the coating. Nb improves the coating's heat and corrosion resistance, while B enhances its strength through grain boundary strengthening. Consequently, AlNbB coatings can significantly extend the life of components operating in high-temperature, corrosive environments.
[0003] AlNbB alloy targets are the sputtering source for AlNbB coatings. These targets are typically prepared using a vacuum melting process. However, this process is characterized by high temperatures and energy consumption, the tendency for Al and B to ablate during the melting process, and difficulty controlling the alloy composition. The hot isostatic pressing process, on the other hand, involves placing metal powder into a can, applying equal pressure in all directions to the can, and simultaneously applying high temperatures and pressure. The powder then sinters under these conditions.
[0004] Compared with vacuum melting, hot isostatic pressing (HIP) requires a low preparation temperature and is easy to control the alloy composition. However, when the Al content is low, the AlNbB alloy target prepared by HIP has a low relative density and low density, which significantly reduces the strength of the coating prepared after sputtering, thereby affecting the coating performance. Although increasing the HIP temperature can increase the relative density of the prepared AlNbB alloy target, due to the low melting point of Al and the high melting points of Nb and B, increasing the HIP temperature can easily cause the Al powder to melt and flow first, resulting in target composition segregation or sheath melting, causing target preparation failure. Summary of the Invention
[0005] In view of the difficulties and shortcomings in the preparation of the above-mentioned AlNbB alloy target, the present application provides an AlNbB alloy target and a preparation method thereof.
[0006] In a first aspect, the present application provides a method for preparing an AlNbB alloy target, which adopts the following technical solution:
[0007] A method for preparing an AlNbB alloy target, the method comprising: pre-sintering, degassing and hot isostatic pressing;
[0008] In the pre-sintering step, a mixed powder consisting of Al powder, Nb powder and B powder is placed in a mold and pre-sintered by spark plasma; the sintering temperature is 350-450°C, the applied pressure is 15-25 MPa, and the heat and pressure holding time is 10-20 minutes;
[0009] In the hot isostatic pressing step, the degassed ingot is hot isostatically pressed at a temperature of 450-550° C., a pressure of 120-170 MPa, and a heat and pressure holding time of 3-6 hours.
[0010] Due to the high melting points of Nb and B, when the Al content is low, the relative density of the AlNbB alloy target produced by hot isostatic pressing is low, and the target density is not high. Simply increasing the hot isostatic pressing temperature to increase the relative density of the target will cause the Al powder to melt and flow first, resulting in target composition segregation or melting of the sheath.
[0011] The spark plasma sintering process is to load metal powder into a graphite mold, apply pressure through the upper and lower punches, and at the same time pass a pulse current between the powder particles to generate high-temperature plasma. The high-temperature plasma activates the surface of the powder particles, and the effective discharge between the particles generates local high temperature, causing the particle surface to melt and then sinter into shape.
[0012] The spark plasma pre-sintering temperature is low, the pre-sintering effect is poor, the relative density of the billet is <80%, and the target material prepared after hot isostatic pressing has a low relative density; the pre-sintering temperature is high, the Al powder melts and flows first, and the composition of the prepared target material is segregated.
[0013] When the hot isostatic pressing temperature is low, the target material produced has a low relative density; when the hot isostatic pressing temperature is high, the aluminum sheath melts and the target material preparation fails.
[0014] The present application adopts a spark plasma pre-sintering process to pre-sinter the AlNbB alloy powder into a billet with a relative density greater than 80%, and then perform hot isostatic pressing. The pre-sintered billet has been consolidated and formed, so the Al will not melt and flow during hot isostatic pressing. The billet is further densified to obtain an AlNbB alloy target with a relative density greater than 98%.
[0015] Optionally, the mold is a graphite mold.
[0016] Optionally, the preparation process of the mixed powder is as follows: using a three-dimensional mixer and zirconia balls to uniformly mix Al powder, Nb powder, and B powder; during the preparation process of the mixed powder, the ball-to-material weight ratio is 1:(3-8).
[0017] The density of A1 powder, B powder and Nb powder is very different. Adding zirconia balls during powder mixing helps to mix the powders evenly. If the ball-to-material weight ratio (zirconia balls: total powder) is too large or too small, the powder mixing effect will be worse, the powder mixing will be uneven, and the elements of the target material will be segregated.
[0018] Optionally, in the degassing step, the pre-sintered blank is placed in an aluminum package and subjected to vacuum heating and degassing. The degassing temperature is 350-450°C and the degassing vacuum degree is 1×10 -2 -1×10-3 Pa.
[0019] Optionally, the Al powder has a purity of ≥99.8wt% and a particle size of 300-500 mesh.
[0020] Optionally, the purity of the Nb powder is ≥99.9wt% and the particle size is 400-500 mesh.
[0021] Optionally, the B powder has a purity of ≥99.8wt% and a particle size of 400-500 mesh.
[0022] Optionally, after the hot isostatic pressing treatment, the hot isostatically pressed ingot is removed from the jacket, and an AlNbB alloy target blank is obtained by wire cutting or saw cutting, and then an AlNbB alloy target with required dimensions is obtained by turning or milling.
[0023] In a second aspect, the present application provides an AlNbB alloy target prepared using the above-mentioned preparation method.
[0024] Optionally, the AlNbB alloy target comprises the following elements in percentages: Nb 1-45 at%, B 1-20 at%, and Al as the balance.
[0025] In summary, this application includes at least one of the following beneficial technical effects:
[0026] (1) This application prepares AlNbB alloy target material through spark plasma pre-sintering + hot isostatic pressing process, which has a short preparation process flow, high production efficiency, no high-temperature melting process, and low energy consumption.
[0027] (2) The raw materials used in the preparation method provided in this application are elemental powders, and the ingredients are flexible, without the need to prepare the intermediate alloy in advance.
[0028] (3) The relative density of the AlNbB alloy target prepared by the preparation method of the present application is above 98%, the structure is dense, the elements are evenly distributed, there is no segregation phenomenon, and the product qualification rate is high. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 This is a process flow chart of the preparation method of the AlNbB alloy target provided in this application. DETAILED DESCRIPTION
[0030] Before describing the embodiments of the present application in detail, it should be understood that the terminology used herein is only for the purpose of describing particular embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the term belongs.
[0031] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. Furthermore, in the description of this application, unless otherwise specified, "plurality" means two or more.
[0032] The endpoints of the ranges and any values disclosed in this application are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values can be combined with each other to obtain one or more new numerical ranges, and these numerical ranges should be considered to be specifically disclosed herein.
[0033] In this application, the term "comprise" or "include" is an open expression, that is, it includes the content specified in this application, but does not exclude other aspects of the content.
[0034] This application provides an AlNbB alloy target. This AlNbB alloy target has a dense structure, a relative density of over 98%, and a uniform element distribution with no segregation. The AlNbB alloy target comprises the following elements: Nb 1-45 at%, B 1-20 at%, with Al as the balance.
[0035] This application also provides a method for preparing the aforementioned AlNbB alloy target. The raw materials used in this preparation method are Al powder, Nb powder, and B powder. The Al powder has a purity of ≥99.8% by weight and a particle size of 300-500 mesh; the Nb powder has a purity of ≥99.9% by weight and a particle size of 400-500 mesh; and the B powder has a purity of ≥99.8% by weight and a particle size of 400-500 mesh.
[0036] Combine Figure 1 , the above preparation method specifically comprises the following steps:
[0037] (1) Preparation of mixed powder: Al powder, Nb powder, B powder and zirconia balls are added to a three-dimensional mixer and mixed evenly. The weight ratio of balls to materials (zirconia balls: total powder) is 1: (3-8) to obtain AlNbB alloy powder.
[0038] (2) Pre-sintering: AlNbB alloy powder is placed in a graphite mold, vacuumed to less than 5 Pa, and the sintering temperature is controlled at 350-450 °C for spark plasma pre-sintering. A pressure of 15-25 MPa is applied, and the heat and pressure holding time is 10-20 min to obtain a pre-sintered blank.
[0039] (3) Degassing: The pre-sintered blank is placed in an aluminum package and degassed by vacuum heating. The degassing temperature is 350-450°C and the degassing vacuum degree is 1×10 -2 -1×10 -3 Pa, to obtain the degassed ingot.
[0040] (4) Hot isostatic pressing: The degassed ingot is hot isostatically pressed at a temperature of 450-550°C, a pressure of 120-170 MPa, and a holding time of 3-6 hours to obtain an ingot after hot isostatic pressing.
[0041] (5) Machining: Remove the jacket from the hot isostatically pressed ingot and obtain the AlNbB alloy target blank by wire cutting or saw cutting. Then, the AlNbB alloy target with the required dimensions is obtained by turning, milling, and other processing methods.
[0042] To make the purpose, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without making any creative work are within the scope of protection of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be understood as limiting this application.
[0043] If no specific techniques or conditions are specified in the examples, the experiments were carried out according to the techniques or conditions described in the literature in the field or according to the product instructions. All reagents or instruments used without specifying the manufacturer are commercially available conventional products.
[0044] The present application is further described in detail below in conjunction with the examples and test results.
[0045] Example
[0046] Example 1
[0047] This embodiment provides an AlNbB alloy target.
[0048] The atomic percentage content of each element is: Nb 25at%, B 10at%, and Al as the balance.
[0049] The preparation method specifically comprises the following steps:
[0050] (1) Preparation of mixed powder: Al powder, Nb powder, B powder and zirconia balls are added into a three-dimensional mixer and mixed evenly. The weight ratio of balls to materials (zirconia balls: total powder) is 1:5 to obtain AlNbB alloy powder.
[0051] (2) Pre-sintering: AlNbB alloy powder was placed in a graphite mold, vacuumed to less than 5 Pa, and the sintering temperature was controlled at 400 °C for spark plasma pre-sintering. A pressure of 20 MPa was applied and the heat and pressure holding time was 15 min to obtain the pre-sintered blank.
[0052] (3) Degassing: The pre-sintered blank is placed in an aluminum package and degassed by vacuum heating. The degassing temperature is 400 °C and the degassing vacuum degree is 2×10 -3 Pa, to obtain the degassed ingot.
[0053] (4) Hot isostatic pressing: The degassed ingot is hot isostatically pressed at a temperature of 500°C, a pressure of 150 MPa, and a holding time of 4 h to obtain an ingot after hot isostatic pressing.
[0054] (5) Machining: Remove the jacket from the hot isostatically pressed ingot and obtain the AlNbB alloy target blank by wire cutting or saw cutting. Then, the AlNbB alloy target with the required dimensions is obtained by turning, milling, and other processing methods.
[0055] The AlNbB alloy target prepared in this embodiment has a dense structure, a relative density of 99.1%, and uniform element distribution without segregation.
[0056] Example 2
[0057] This embodiment provides an AlNbB alloy target. This embodiment differs from Embodiment 1 in that the atomic percentage content of each element in the AlNbB alloy target is: Nb 45 at%, B 20 at%, with Al as the balance. The remaining steps remain the same as in Embodiment 1.
[0058] Example 3
[0059] This embodiment provides an AlNbB alloy target. This embodiment differs from Embodiment 1 in that the atomic percentage content of each element in the AlNbB alloy target is: Nb 1 at%, B 1 at%, with Al as the balance. The remaining steps remain the same as in Embodiment 1.
[0060] Example 4
[0061] Examples 4-15 provide an AlNbB alloy target material. The difference between the above examples and Example 1 lies in the setting of some parameters in spark plasma pre-sintering and hot isostatic pressing, as shown in Table 1. The remaining steps are consistent with Example 1.
[0062] Specifically, the difference between Example 1 and Examples 4-15 is that:
[0063] The difference between Example 1 and Examples 4-5 lies in the sintering temperature in spark plasma pre-sintering.
[0064] The difference between Example 1 and Examples 6-7 lies in the pressure applied during spark plasma pre-sintering.
[0065] The difference between Example 1 and Examples 8-9 lies in the heat preservation and pressure holding time during spark plasma pre-sintering.
[0066] The difference between Example 1 and Examples 10-11 is the sintering temperature.
[0067] The difference between Example 1 and Examples 12-13 lies in the pressure during hot isostatic pressing.
[0068] The difference between Example 1 and Examples 14-15 lies in the holding time during hot isostatic pressing.
[0069] The test results of the AlNbB alloy target prepared in the above embodiment are shown in Table 1.
[0070] Table 1 Test results of AlNbB alloy targets prepared in the above examples
[0071]
[0072] Comparative Example
[0073] Comparative Example 1
[0074] This comparative example provides an AlNbB alloy target. The difference between this target and Example 1 is that step (2) is omitted, and spark plasma pre-sintering is not performed; the AlNbB alloy powder is directly loaded into an aluminum sheath, degassed, and then hot isostatically pressed. The remaining steps are consistent with Example 1.
[0075] In this comparative example, since spark plasma pre-sintering was not performed, the density of the prepared target material was not high, with a relative density of 97.2%.
[0076] By comparing the solutions of the present application and Comparative Example 1, it can be seen that due to the high melting points of Nb and B, when the Al content is low, the AlNbB alloy target prepared by the hot isostatic pressing process has a low relative density and the target density is not high.
[0077] Comparative Example 2
[0078] This comparative example provides an AlNbB alloy target material. The difference between this comparative example and Example 1 is that the sintering temperature in step (2) spark plasma pre-sintering is 500° C.; the remaining steps are consistent with Example 1.
[0079] In this comparative example, since the pre-sintering temperature is relatively high, the Al powder melts and flows first, and the components of the prepared target material are segregated, with a relative density of 98.1%.
[0080] Comparative Example 3
[0081] This comparative example provides an AlNbB alloy target material. The difference between this comparative example and Example 1 is that the sintering temperature in step (2) spark plasma pre-sintering is 300° C.; the remaining steps are consistent with Example 1.
[0082] In this comparative example, due to the low pre-sintering temperature, the pre-sintering effect is poor, the relative density of the blank is less than 80%, and the relative density of the target material obtained after hot isostatic pressing is 97.5%.
[0083] By comparing the schemes of the present application and comparative examples 2-3, it can be seen that the spark plasma pre-sintering temperature is low, the pre-sintering effect is poor, the relative density of the blank is <80%, and the relative density of the target material obtained after hot isostatic pressing is low; the pre-sintering temperature is high, the Al powder melts and flows first, and the composition of the prepared target material is segregated.
[0084] Comparative Example 4
[0085] This comparative example provides an AlNbB alloy target material. The difference between this comparative example and Example 1 is that the hot isostatic pressing temperature in step (4) is 600°C; the remaining steps are consistent with Example 1.
[0086] In this comparative example, due to the high hot isostatic pressing temperature, the aluminum sheath melted and the target preparation failed.
[0087] Comparative Example 5
[0088] This comparative example provides an AlNbB alloy target material. The difference between this comparative example and Example 1 is that the hot isostatic pressing temperature in step (4) is 400°C; the remaining steps are consistent with Example 1.
[0089] In this comparative example, since the hot isostatic pressing temperature is relatively low, the relative density of the target material obtained after hot isostatic pressing is 97.6%.
[0090] By comparing the solutions of this application and comparative examples 4-5, it can be seen that the hot isostatic pressing temperature is low and the relative density of the target material obtained is low; the hot isostatic pressing temperature is high, which will cause the Al powder to melt and flow first, resulting in target material component segregation or sheath melting, and target material preparation failure.
[0091] The present application adopts a spark plasma pre-sintering process to pre-sinter the AlNbB alloy powder into a billet with a relative density greater than 80%, and then perform hot isostatic pressing. The pre-sintered billet has been consolidated and formed, so the Al will not melt and flow during hot isostatic pressing. The billet is further densified to obtain an AlNbB alloy target with a relative density greater than 98%.
[0092] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.
[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application 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 make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.
Claims
1. A method for preparing an AlNbB alloy target, characterized in that: The preparation method comprises: pre-sintering, degassing and hot isostatic pressing; In the pre-sintering step, a mixed powder consisting of Al powder, Nb powder and B powder is placed in a mold and pre-sintered by spark plasma; the sintering temperature is 350-450°C, the applied pressure is 15-25 MPa, and the heat and pressure holding time is 10-20 minutes; In the hot isostatic pressing step, the degassed ingot is hot isostatically pressed at a temperature of 450-550° C., a pressure of 120-170 MPa, and a heat and pressure holding time of 3-6 hours.
2. The preparation method according to claim 1, characterized in that The mold is a graphite mold.
3. The preparation method according to claim 1, characterized in that The preparation process of the mixed powder is as follows: using a three-dimensional mixer and zirconia balls to uniformly mix Al powder, Nb powder, and B powder; during the preparation process of the mixed powder, the ball-to-material weight ratio is 1:(3-8).
4. The preparation method according to claim 1, characterized in that In the degassing step, the pre-sintered blank is placed in an aluminum package and vacuum heated for degassing. The degassing temperature is 350-450°C and the degassing vacuum degree is 1×10 -2 -1×10 -3 Pa.
5. The preparation method according to claim 1, characterized in that The Al powder has a purity of ≥99.8 wt % and a particle size of 300-500 meshes.
6. The preparation method according to claim 1, characterized in that The purity of the Nb powder is ≥99.9wt% and the particle size is 400-500 mesh.
7. The preparation method according to claim 1, characterized in that The B powder has a purity of ≥99.8wt% and a particle size of 400-500 meshes.
8. The preparation method according to claim 1, characterized in that After the hot isostatic pressing treatment, the hot isostatically pressed ingot is removed from the jacket, and an AlNbB alloy target blank is obtained by wire cutting or saw cutting, and then an AlNbB alloy target with a required external size is obtained by turning and milling.
9. An AlNbB alloy target prepared by the preparation method according to any one of claims 1 to 8.
10. The AlNbB alloy target according to claim 9, wherein The AlNbB alloy target material includes the following elements in percentages: Nb 1-45 at%, B 1-20 at%, and Al as the balance.