High tensile ductility and tensile strength can alloy and method of making

Abstract

The application discloses a kind of high tensile ductility and tensile strength can alloy and preparation method.The chemical formula of the can alloy is Fe v Ni w Co x Al y Ta z Wherein, 60 < v ≤ 70, 40 < w ≤ 50, 0 < x ≤ 10, 0 < y ≤ 10, 1 < z ≤ 5.The main element of preparation method is face-centered cubic Fe-Ni alloy.By introducing Co element in solid solution Fe-Ni for chemical control, obtain the can alloy with thermal expansion performance, but due to the low tensile strength of face-centered cubic solid solution.By introducing a small amount of Al and Ta element, intracrystalline precipitation coherent (Ni, Fe) 3 (Al, Ta) ordered phase, and then realize high tensile ductility and tensile strength.The synthesis steps of the high tensile ductility and tensile strength can alloy of the application are simple and easy to realize, and the raw material cost is low, realize the mechanical property and the thermal expansion attribute of can alloy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-precision instrument technology and chip packaging, and particularly relates to a high-tensile ductility and tensile strength Kovar alloy and a preparation method. BACKGROUND

[0002] The Kovar alloy is 4J29 alloy, the alloy has a thermal expansion coefficient (3-5*10 -6 K -1 ) similar to that of borosilicate hard glass at 20-450 DEG C, a higher Curie point, and good low-temperature structure stability. The alloy is mainly applied in the field of high-precision instruments, for example, glass sealing of electrical vacuum components such as emission tubes, oscillation tubes, ignition tubes, magnetrons, transistors, sealed plugs, relays, lead-out wires of integrated circuits, chassis, housings, supports, etc. In the application, the expansion coefficients of the glass and the alloy are matched. In the processing process, appropriate heat treatment should be performed to ensure that the material has good deep drawing performance. However, the classic Kovar alloy has a relatively high Co content (16-22%), which is expensive, and more importantly, the increase of the Co content leads to the decrease of the stability of the austenitic face-centered cubic structure, resulting in the instability of the thermal expansion coefficient. With the expansion of the application field, there is an increasing demand for Kovar alloys with mechanical properties in the fields of high-pressure transportation line cores, LNG transportation ship hull materials, etc. Therefore, it is necessary to study a high-tensile ductility and tensile strength Kovar alloy and a preparation method to overcome the shortcomings of the prior art and solve or alleviate one or more of the above problems. SUMMARY

[0003] The present application aims to solve the problems of the prior art and provides a high-tensile ductility and tensile strength Kovar alloy and a preparation method. The Co, Al and Ta elements are introduced into the Fe-Ni-based face-centered cubic solid solution (FCC) in the preparation method, a high-tensile ductility and tensile strength Kovar alloy is obtained, the Co element is used to control the magnetic interaction to control the thermal expansion performance, the Al and Ta elements are used to precipitate a small amount of ordered second phase (L12), and the strengthening and toughening of the mechanical properties are realized. The synthesis steps are simple and easy to implement, the Co content is low, the advantages of low cost and more stable phase structure are achieved, the thermal expansion of the Kovar alloy is realized, and the mechanical properties are also significantly improved.

[0004] The present application adopts the following technical scheme: a high-tensile ductility and tensile strength Kovar alloy, the chemical formula of the Kovar alloy is Fe v Ni w Co x Al yTaz, wherein 60<v≤70at%, 40<w≤50at%, 0<x≤10at%, 0<y≤10at%, 1<z≤5at%, the Kovar alloy is a coherent two-phase alloy having a matrix phase and an ordered phase, the matrix phase is a Fe-Ni-Co phase, the ordered phase is a (Ni, Fe)3(Al, Ta) phase, the space group of the matrix phase is Fm-3m, and the space group of the ordered phase is Pm-3m.

[0005] Furthermore, the tensile strength of the Kovar alloy at room temperature is 0.8-1.2 GPa, the tensile ductility is 20.0-40.0%, and the thermal expansion coefficient is 3-5×10 -6 K -1 .

[0006] Furthermore, the chemical formula of the Kovar alloy is Fe 65 Ni 47 Co4Al6Ta 2， The tensile strength at room temperature is 1.0 GPa, the tensile ductility is 40.0%, and the thermal expansion coefficient α is 1.0 GPa at room temperature, and the tensile ductility is 40.0% at room temperature, ... l 3.81×10 -6 K -1 .

[0007] Furthermore, the chemical formula of the Kovar alloy is Fe 65 Ni 42 Co4Al6Ta 2， The tensile strength at room temperature is 1.2GPa, the tensile ductility is 30.0%, and the thermal expansion coefficient α is 1.2GPa at room temperature, and the tensile ductility is 30.0% at room temperature, ... l 4.81×10 -6 K -1 .

[0008] Furthermore, the chemical formula of the Kovar alloy is Fe 65 Ni 47 Co4Al6Ta 2， The tensile strength at room temperature is 0.8GPa, the tensile ductility is 20.0%, and the thermal expansion coefficient α is 0.8GPa at room temperature, and the tensile ductility is 20.0% at room temperature, ... l 3.23×10 -6 K -1 .

[0009] Another object of the present invention is to provide a method for preparing the above-mentioned Kovar alloy, characterized in that the method comprises the following steps:

[0010] S1) Fe, Ni, Co, Al and Ta raw materials are weighed according to the design ratio, mixed and reserved;

[0011] S2) The mixed material after S1) is uniformly melted by an arc furnace and suction cast into a large-size block;

[0012] S3) The large-size block obtained in S2) is placed in a protective atmosphere for homogenization annealing to obtain a sample;

[0013] S4) The sample obtained in S3) is subjected to rolling treatment to obtain a rolled sample;

[0014] S5) After the recrystallization + aging heat treatment annealing of the rolled sample obtained in S4) is completed, the Kovar alloy with high tensile ductility and tensile strength is obtained.

[0015] Further, the purity of Fe, Ni, Co, Al and Ta in S1) is > 99.5 %.

[0016] Further, the specific process of S3) is: placed in a protective atmosphere of vacuum or inert gas, heated to 1000-1200 DEG C, and the annealing treatment time is 1-24 h.

[0017] Further, the cold rolling reduction of S4) is 50-90 %.

[0018] Further, the specific process of S5) is: recrystallization temperature is 900-1000 DEG C for 5-60 min, and aging temperature is 600-700 DEG C for 1-24 h.

[0019] Compared with the prior art, the present application can obtain the following technical effects:

[0020] The high tensile ductility and tensile strength Kovar alloy has a shape and size that is not very small with temperature, has high dimensional stability, precision and long service life; more importantly, the low Co content reduces the production cost and provides a stable phase structure.

[0021] The high tensile ductility and tensile strength Kovar alloy has excellent tensile ductility and tensile strength, overcoming the technical difficulties of traditional alloy mechanical properties and thermal expansion properties.

[0022] Of course, any product implementing the present application does not necessarily need to achieve all the technical effects described above at the same time. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 For the high tensile ductility and tensile strength Kovar alloy of the present application, Fe 65 Ni 47X-ray diffraction structure refinement pattern and high angle annular dark field scanning transmission electron microscopy image of Co4Al6Ta2 powder at 300 K.

[0024] Figure 2 For the high tensile ductility and tensile strength Kovar alloy of the embodiments of the present application, Fe 65 Ni 47 Co4Al6Ta2 thermal expansion and tensile-stress strain curve.

[0025] Figure 3 For the high tensile ductility and tensile strength Kovar alloy thermal expansion and tensile-stress strain curve obtained by the preparation method of the present application. DETAILED DESCRIPTION

[0026] The specific embodiments of the present application will be described in detail below with reference to specific drawings. It should be noted that the technical features described in the following embodiments or combinations of technical features should not be considered in isolation, and they can be combined with each other to achieve better technical effects.

[0027] The present application is a high tensile ductility and tensile strength Kovar alloy, whose chemical formula is Fe v Ni w Co x Al y Ta z , wherein 60 < v(Fe) ≤ 70 at%, 40 < w(Ni) ≤ 50 at%, 0 < x(Co) ≤ 10 at%, 0 < y(Al) ≤ 10, 1 < z(Ta) ≤ 5 at%. As a specific embodiment, when the high tensile ductility and tensile strength Kovar alloy is Fe 65 Ni 47 Co4Al6Ta2, the Fe 65 Ni 47 Co4Al6Ta2 exhibits the thermal expansion properties of Kovar alloy in the temperature range of 100-410 K, and the thermal expansion coefficient α l is 3.81 × 10 -6 , the tensile strength at room temperature reaches σ US = 1.0 GPa, and the tensile strain reaches ε f = 40.0 %.

[0028] The preparation method comprises the following steps:

[0029] S1) Prepare Fe v Ni w Co x Al y Ta zwherein 60 < v(Fe) < 70 at%, 40 < w(Ni) < 50 at%, 0 < x(Co) < 10 at%, 0 < y(Al) < 10 at%, 1 < z(Ta) < 5 at% raw materials;

[0030] S2) mixing different element raw materials in S1);

[0031] S3) melting the mixed raw materials uniformly by an electric arc furnace and suction casting into a large-size block;

[0032] S4) placing the sample melted uniformly under a protective atmosphere for homogenization annealing;

[0033] S5) further performing a rolling treatment on the sample;

[0034] S6) obtaining the high tensile ductility and tensile strength Kovar alloy after annealing by performing a recovery recrystallization + aging heat treatment on the rolled sample.

[0035] In the preparation method, the disordered FCC phase is a matrix phase, and the ordered L12 phase is a second phase. The low expansion performance is maintained by the matrix phase, and the mechanical behavior is improved by the second phase. The high tensile ductility and tensile strength Kovar alloy is obtained through the synergistic effect of the two phases.

[0036] Example 1

[0037] The high tensile ductility and tensile strength Kovar alloy with the composition Fe 65 Ni 47 Co4Al6Ta2is synthesized by an electric arc furnace melting method, and the specific operation is performed according to the following steps:

[0038] S1) preparing Fe 65 Ni 47 Co4Al6Ta2required raw materials, and the raw materials are weighed according to the stoichiometric ratio, preferably, the purity of the raw materials is > 99.5%;

[0039] S2) mixing different element raw materials in S1);

[0040] S3) melting the mixed raw materials uniformly by an electric arc furnace and suction casting into a large-size block;

[0041] S4) placing the sample melted uniformly under a protective atmosphere at 1200°C for 6h for homogenization annealing;

[0042] S5) further performing a cold rolling treatment of 70% on the sample to obtain a plate;

[0043] S6) obtaining the high tensile ductility and tensile strength Kovar alloy by annealing the rolled sample at 1000°C for 5min for recrystallization, and then aging at 600°C for 8h.

[0044] The high tensile ductility and tensile strength of the Kovar alloy Fe 65 Ni 47 Co4Al6Ta2 was measured by X-ray diffraction test and structure refinement, confirming that the composite material is composed of FCC phase, space group Fm-3m, L12 phase, space group Pm-3m two phases. The spherical aberration electron microscopy test at atomic resolution confirms the FCC / L12 coherent dual-phase microstructure.

[0045] The high tensile ductility and tensile strength of the Kovar alloy Fe 65 Ni 47 Co4Al6Ta2 was measured by thermal expansion, which shows low expansion characteristics in the temperature range of 100~410 K, and the thermal expansion coefficient (α l ) is 3.81×10 -6 K -1 .

[0046] The high tensile ductility and tensile strength of the Kovar alloy Fe 65 Ni 47 Co4Al6Ta2 was measured by tensile engineering stress-strain test, and the tensile strength at room temperature reaches σ US = 1.0 GPa, and the tensile strain reaches ε f = 40.0%.

[0047] As Figure 1 shown in the high tensile ductility and tensile strength of the Kovar alloy Fe 65 Ni 47 Co4Al6Ta2 powder X-ray diffraction refinement pattern and high-angle annular dark-field spherical aberration electron microscopy at 300 K. From the figure, it can be seen that the high strength and low expansion composite material of the application is FCC and L12 dual-phase, and the crystal structure model is correct; the spherical aberration electron microscopy test at atomic resolution confirms the FCC / L12 coherent dual-phase microstructure.

[0048] As Figure 2 shown in the high tensile ductility and tensile strength of the Kovar alloy Fe 65 Ni 47 Co4Al6Ta2 thermal expansion and tensile stress-strain curve, from the thermal expansion curve of the Fe 65 Ni 47 Co4Al6Ta2 of the application, it can be seen that it respectively shows low expansion characteristics (3.81×10 -6 K -1 ) in the temperature range of 100~410 K, and the tensile strength at room temperature reaches σ US= 1.0 GPa, the tensile strain reaches  f = 40.0 %.

[0049] Example 2

[0050] Ta, Ni, Co three components have the greatest influence on thermal expansion and mechanical behavior, so the composition of the application is respectively prepared Fe 65 Ni 40 Co4Al6Ta 0+x (x = 1, 3, 4, 5), Fe 65 Ni 40+yCo4 Al6Ta2(y = 40, 42, 44, 50) and Fe 65 Ni 40 Co 0+z Al6Ta2(z = 0, 2, 6, 8, 10) high tensile ductility and tensile strength of the alloy is synthesized by electric arc furnace melting method, the specific operation is carried out according to the following steps:

[0051] S1) preparation of Fe 65 Ni 40 Co4Al6Ta 0+x (x = 1, 3, 4, 5), Fe 65 Ni 40+yCo4 Al6Ta2(y = 40, 42, 44, 50) and Fe 65 Ni 40 Co 0+z Al6Ta2(z = 0, 2, 6, 8, 10), and according to the stoichiometric ratio, preferably, the purity of raw materials is > 99.5%;

[0052] S2) mixing different element raw materials in S1);

[0053] S3) the mixed raw materials are melted uniformly by electric arc furnace, and are suction cast into large size block;

[0054] S4) the sample melted uniformly is placed in 1200 ℃ protective atmosphere for homogenization annealing for 6h;

[0055] S5) the sample is further treated by cold rolling 70% to obtain a plate;

[0056] S6) the rolled sample is annealed at 1000 ℃ for 5min to recrystallize, and then is aged at 650℃ for 8h, to obtain the high tensile ductility and tensile strength of the alloy.

[0057] Example 2, the high tensile ductility and tensile strength of the alloy Fe 65 Ni 40Co4Al6Ta 0+x (x =1, 3, 4, 5)、Fe 65 Ni 40+xCo4 Al6Ta2(y = 40, 42, 44, 50)and Fe 65 Ni 40 Co 0+z Al6Ta2(z = 0, 2, 6, 8, 10)thermal expansion curve, it is known that it respectively shows low expansion characteristics (3.0-5.0×10 -6 K -1 ).

[0058] As Figure 3 shown the high tensile ductility and tensile strength of the vanadium alloy Fe 65 Ni 40 Co4Al6Ta 0+x (x = 1,3, 4, 5)、Fe 65 Ni 40+yCo4 Al6Ta2(y = 40, 42, 44, 50)and Fe 65 Ni 40 Co 0+z Al6Ta2(z = 0, 2, 6, 8, 10)thermal expansion curve, it is known that it respectively shows low expansion characteristics (3.0-5.0×10 - 6 K -1 ).

[0059] The above provides a kind of high tensile ductility and tensile strength vanadium alloy and preparation method of example of the present application, are described in detail.The above example is only for helping to understand the method of the present application and its core idea;Meanwhile, for the general technical personnel of the art, according to the idea of the present application, there will be changes in specific implementation mode and application range, and the above-mentioned, the content of the specification should not be understood as the limitation of the present application.

[0060] As used in the specification and claims, certain terms have particular meanings. One skilled in the art will understand that different manufacturers can refer to a component by different names. The specification and claims should not be construed as limited to components by a particular name, but should be construed by the component's function. As used in the specification and claims, "comprising" and "including" are meant to be interpreted as specifying open-ended claims that are not limited to the listed elements. "Approximately" means within an acceptable error range for the corresponding function, which will vary from one context to another. The description that follows is intended to provide a better understanding of the preferred embodiments of the present application, and is not intended to be a complete description of all possible embodiments of the present application. The description serves only to illustrate the general principles of the present application, and is not meant to limit the present application to specific embodiments.

[0061] It should also be noted that the terms "comprising," "including," and "having" or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element preceded by "comprises... a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the recited element.

[0062] It should be understood that the term "and / or" as used herein is merely an open-ended descriptive term indicating that three conditions exist, for example, A and / or B, can mean: A exists alone, A and B exist together, and B exists alone. In addition, the character " / " as used herein generally represents an "or" relationship between the front and rear associated objects.

[0063] The above specification and description of various preferred embodiments of the present application has been presented for the purpose of illustration and description. It is not intended to be exhaustive or to limit the application to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching or knowledge of the skilled artisan, or logical deductions permitted under the doctrines of equivalents to the extent that such do not depart from the spirit and scope of the application. Changes can be made by one skilled in the art, which are commensurate with the application, without departing from the spirit and scope of the application as defined by the following claims.

Claims

1. A Kovar alloy having high tensile ductility and tensile strength, characterized in that: The chemical formula of the Kovar alloy is Fe v Ni w Co x Al y Ta z , wherein, according to at: 60<v≤70, 40<w≤50, 0<x≤10, 0<y≤10, 1<z≤5, the Kovar alloy is a coherent two-phase alloy having a matrix phase and an ordered phase, the matrix phase is an Fe-Ni-Co phase, the ordered phase is a (Ni, Fe)3(Al, Ta) phase, the space group of the matrix phase is Fm-3m, and the space group of the ordered phase is Pm-3m; wherein the Co element is used to regulate the magnetic interaction to control the thermal expansion properties, while the Al and Ta elements are used to precipitate a small amount of ordered second phase L12. The Kovar alloy has a tensile strength of 0.8-1.2 GPa and a tensile ductility of 20.0-40.0% at room temperature. In the temperature range of 100-410 K, the thermal expansion coefficient is (3-5)×10 -6 K -1 .

2. The Kovar alloy according to claim 1, characterized in that The chemical formula of the Kovar alloy is Fe 65 Ni 47 Co4Al6Ta 2， The tensile strength at room temperature is 1.0 GPa, the tensile ductility is 40.0%, and the thermal expansion coefficient α is 1.0 GPa at room temperature, and 40.0% at room temperature. l 3.81×10 -6 K -1 .

3. The Kovar alloy according to claim 1, characterized in that The chemical formula of the Kovar alloy is Fe 65 Ni 44 Co6Al6Ta 2， The tensile strength at room temperature is 1.2 GPa, the tensile ductility is 30.0%, and the thermal expansion coefficient α is 1.2 GPa at room temperature, and the tensile ductility is 30.0% at room temperature, ... l is 4.81×10 -6 K -1 .

4. The Kovar alloy according to claim 1, characterized in that The chemical formula of the Kovar alloy is Fe 65 Ni 40 Co8Al6Ta 2， The tensile strength at room temperature is 0.8 GPa, the tensile ductility is 20.0%, and the thermal expansion coefficient α is 0.8 GPa at room temperature, and the tensile ductility is 20.0% at room temperature, ... l 3.23×10 -6 K -1 .

5. A method for preparing the Kovar alloy according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: S1) Fe, Ni, Co, Al and Ta raw materials are weighed according to the designed ratio, mixed and set aside; S2) melting the mixed material processed in S1) uniformly in an electric arc furnace, and suction casting the mixture into large-sized blocks; S3) placing the large-sized block obtained in S2) in a protective atmosphere for homogenization annealing to obtain a sample; S4) rolling the sample obtained in S3) to obtain a rolled sample; S5) After the rolled sample obtained in S4) is subjected to recrystallization and aging heat treatment annealing, a Kovar alloy with high tensile ductility and tensile strength is obtained.

6. The method according to claim 5, characterized in that The purity of Fe, Ni, Co, Al and Ta in S1) is >99.5%.

7. The method according to claim 5, characterized in that The specific process of S3) is: heating to 1000° C.-1200° C. under vacuum or inert gas protective atmosphere, and the annealing time is: 1-24 hours.

8. The method according to claim 5, characterized in that The cold rolling reduction in step S4) is 50-90%.

9. The method according to claim 5, characterized in that The specific process of S5) is: annealing at a recrystallization temperature of 900-1000° C. for 5-60 minutes, and annealing at an aging temperature of 600-700° C. for 1-24 hours.

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