CN114260432A - Production method and device of crystal grain coarsening resistant copper ingot and crystal grain coarsening resistant copper ingot - Google Patents

Abstract

The invention relates to a production method and a device of a crystal grain coarsening resistant copper ingot and the crystal grain coarsening resistant copper ingot, wherein the production method comprises the following steps: preheating and drying the cathode copper plate with the surface segregation tumor removed to obtain a dried copper plate; putting the dried copper plate into a smelting furnace for melting, adding the micro-alloy elements and uniformly stirring; the microalloy element is at least one selected from Ca, Cr, S, Se, Te or Zr; casting operation is carried out by adopting a vertical semi-continuous casting method, the casting speed is 50-100mm/min, and mechanical vibration and inert gas protection are applied to a cast crystallizer to obtain the crystal grain coarsening resistant copper ingot. According to the production method of the copper resistant to grain coarsening, the micro-alloying elements form dispersed phases or grain boundary segregation in the copper matrix, so that the effects of pinning the grain boundary and inhibiting the growth of recrystallized grains are achieved, and meanwhile, the micro-alloying elements have low solid solubility and have small influence on the conductivity of the copper.

Description

Production method and device of crystal grain coarsening resistant copper ingot and crystal grain coarsening resistant copper ingot

Technical Field

The invention relates to the field of metal materials, in particular to a method and a device for producing a grain coarsening resistant copper ingot and the grain coarsening resistant copper ingot.

Background

Pure copper has good electric and thermal conductivity, so that the pure copper is widely applied to electrical and electronic or thermal conductive devices. Generally, pure copper will undergo significant grain coarsening at high temperatures, and this grain coarsening phenomenon will affect the material properties and apparent quality of the copper. This limits the application of pure copper in the technical fields of high-temperature brazing, direct copper cladding of ceramic copper clad laminate, etc.

The existing means for inhibiting the growth of high-temperature crystal grains of copper materials mainly adopts Cu/Al₂O₃The composite material is high in manufacturing cost and low in manufacturing efficiency, the prepared material is small in specification, and the electric conduction and heat conduction performance of the material is reduced to a certain extent. These disadvantages all act as obstacles limiting the application of copper-based composites.

Disclosure of Invention

In view of the above, it is necessary to provide a method and an apparatus for producing a grain coarsening resistant copper ingot, and a grain coarsening resistant copper material, which address at least one of the above-mentioned problems.

In a first aspect, the present application provides a method for producing a grain coarsening resistant copper ingot, comprising the steps of:

preheating and drying the cathode copper plate with the surface segregation tumor removed to obtain a dried copper plate;

putting the dried copper plate into a smelting furnace for melting, adding the micro-alloy elements and uniformly stirring; the microalloy element is selected from at least one of Ca, Cr, S, Se, Te or Zr, and the percentage content of the microalloy element is less than or equal to 0.045%;

casting operation is carried out by adopting a vertical semi-continuous casting method, the casting speed is 50-100mm/min, and mechanical vibration and inert gas protection are applied to a cast crystallizer to obtain the crystal grain coarsening resistant copper ingot.

In certain implementations of the first aspect, the trace elements have a solid solubility in copper of 0.03% or less at room temperature, and the second phase formed in the copper matrix has a melting point of 800 ℃ or less.

With reference to the first aspect and the foregoing implementation manners, in certain implementation manners of the first aspect, the preheating temperature of the preheating drying is 300 to 500 ℃.

With reference to the first aspect and the foregoing implementations, in certain implementations of the first aspect, the copper content of the cathode copper plate is greater than or equal to 99.99% by mass.

With reference to the first aspect and the foregoing implementation manners, in some implementation manners of the first aspect, the step of placing the dried copper plate into a smelting furnace for melting further includes adding a covering agent to the surface of the molten copper to cover the surface of the molten copper.

With reference to the first aspect and the implementations described above, in certain implementations of the first aspect, the capping agent is a neutral capping agent.

With reference to the first aspect and the foregoing implementation manners, in certain implementation manners of the first aspect, the step of applying mechanical vibration and inert gas shielding to the casting mold includes: and applying mechanical vibration with preset frequency and preset amplitude to the crystallizer, wherein the preset frequency is 30-300 times/min, and the preset amplitude is 0.1-2.5 mm.

With reference to the first aspect and the foregoing implementation manners, in certain implementation manners of the first aspect, the step of applying mechanical vibration and inert gas shielding to the casting mold includes: the flow rate of the inert gas is 3-20L/h, and the inert gas is nitrogen and/or argon.

In a second aspect, the invention provides a production device of a crystal grain coarsening resistant copper cast ingot, which comprises a crystallizer, a cover body, an air inlet pipe and a casting machine pouring pipe; the cover body is arranged on the top opening of the crystallizer;

the casting machine pouring pipe can extend into the containing cavity of the crystallizer from the pouring port of the cover body, a plurality of air outlets are arranged on the side wall of the pouring port of the cover body, and the air outlets are connected with the air inlet pipe.

In a third aspect, the invention provides a crystal grain coarsening resistant copper ingot which is produced by the production method of the crystal grain coarsening resistant copper ingot according to any one of the first aspect of the invention.

The technical scheme provided by the embodiment of the invention has the following beneficial technical effects:

according to the production method of the grain coarsening resistant copper ingot, the dispersed phase or grain boundary segregation is formed in the copper matrix through the microalloying elements, so that the effects of pinning a grain boundary and inhibiting the growth of recrystallized grains are achieved, and meanwhile, the influence on the conductivity of copper is small due to the low solid solubility of the microalloying elements.

Additional aspects and advantages of the present invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

FIG. 1 is a schematic flow chart of a method for producing a copper ingot resistant to grain coarsening according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a production apparatus for a grain coarsening-resistant copper ingot according to an embodiment of the present invention.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Possible embodiments of the invention are given in the figures. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein by the accompanying drawings. The embodiments described by way of reference to the drawings are illustrative for the purpose of providing a more thorough understanding of the present disclosure and are not to be construed as limiting the present invention. Furthermore, if a detailed description of known technologies is not necessary for illustrating the features of the present invention, such technical details may be omitted.

It will be understood by those skilled in the relevant art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is to be understood that the term "and/or" as used herein is intended to include all or any and all combinations of one or more of the associated listed items.

The technical solution of the present invention and how to solve the above technical problems will be described in detail with specific examples.

The embodiment of the first aspect of the invention application provides a method for producing a copper ingot resistant to grain coarsening, as shown in figure 1, comprising the following steps:

s100: and preheating and drying the cathode copper plate with the surface segregation tumor removed to obtain a dried copper plate. The cathode copper plate is adopted as a main raw material, and optionally, the copper content of the cathode copper plate is greater than or equal to 99.99 percent in percentage by mass. And (3) removing the segregation tumor on the surface of the copper plate in advance, and preheating and drying, wherein the preheating temperature of the preheating and drying is 300-500 ℃ optionally.

S200: putting the dried copper plate into a smelting furnace for melting, adding the micro-alloy elements and uniformly stirring; the microalloy element is at least one of Ca, Cr, S, Se, Te or Zr, and the percentage content of the microalloy element is less than or equal to 0.045%. And (3) putting the preheated and dried cathode copper plate into a smelting furnace, and heating to 1150-1300 ℃ to completely melt the cathode copper plate. The solid solubility of the trace elements in copper at room temperature is less than or equal to 0.03%, and the melting point of a second phase formed in the copper matrix is not lower than 800 ℃. The microalloying elements can be added in the form of simple substances or master alloys, for example, refractory or easily-burnt elements such as Cr, Zr and the like are added through master alloys such as CuCr7 or CuZr5 and the like. Ca. Zr and other elements easy to burn and lose are added in excess in advance according to the burning and losing proportion.

S300: casting operation is carried out by adopting a vertical semi-continuous casting method, the casting speed is 50-100mm/min, and mechanical vibration and inert gas protection are applied to a cast crystallizer to obtain the crystal grain coarsening resistant copper ingot. Introducing dry inert gas into the furnace, and stirring the melt to ensure that the components of the melt are uniform. The casting speed is selected to be 50-100mm/min, namely the speed of injecting molten metal into the crystallizer is increased by 50-100mm per minute, and the casting temperature is 1120-1220 ℃. The crystallizer is made of copper or high copper alloy. Optionally, the step of melting the dried copper plate in a melting furnace further includes adding a covering agent on the surface of the molten copper to cover the surface of the molten copper. And a covering agent is adopted to tightly cover the surface of the copper liquid in the casting process. The covering agent is a neutral covering agent, such as borax.

According to the production method of the grain coarsening resistant copper ingot, the dispersed phase or grain boundary segregation is formed in the copper matrix through the microalloying elements, so that the grain boundary is pinned, and the growth of recrystallized grains is inhibited.

Optionally, the step of applying mechanical vibration and inert gas shielding to the cast mold in S300 specifically includes: and applying mechanical vibration with a preset frequency and a preset amplitude to the crystallizer, wherein the preset frequency is 30-300 times/min, and the preset amplitude is 0.1-2.5 mm. In the process of injecting the copper liquid into the crystallizer, mechanical vibration is applied to the crystallizer, the vibration frequency is 30-300 times/min, and the vibration amplitude is 0.1-2.5 mm. Meanwhile, cooling water is also required to be applied to the crystallizer, wherein the primary cooling water flow is 300-900L/min, and the secondary cooling water flow is 100-900L/min. The primary cooling water refers to cooling water in a pipeline in the crystallizer, and the secondary cooling water is cooling water directly sprayed to the ingot below.

Optionally, in certain implementations of embodiments of the first aspect, the step of applying mechanical vibration and inert gas shielding to the casting mold comprises: the flow rate of the inert gas is 3-20L/h, and the inert gas is nitrogen and/or argon. Inert gas is introduced above the crystallizer to protect the melt, and the structure of the crystallizer and the gas protection device refers to fig. 2. The inert gas is dry high-purity nitrogen or argon, the gas flow is 3-20L/h, and when the nitrogen is adopted, the corresponding flow is preferably 10-20L/h. When argon is adopted, the corresponding flow is preferably 3-10L/h.

Based on the same technical concept, an embodiment of the second aspect of the present application provides a device for producing a copper ingot resistant to grain coarsening, as shown in fig. 2, comprising a crystallizer, a cover body, an air inlet pipe and a casting pipe of a casting machine; the cover body is arranged on the top opening of the crystallizer;

the casting machine pouring pipe can extend into the containing cavity of the crystallizer from the pouring gate of the cover body, a plurality of air outlets are arranged on the side wall of the pouring gate of the cover body, and the air outlets are connected with the air inlet pipe. The cover body of the production device comprises a frame, an air outlet hole, an air inlet pipe and the like, the cover body is placed above the crystallizer, and the pouring pipe penetrates through the middle opening of the cover body and can extend into the inner cavity of the crystallizer.

In a third aspect of the present application, there is provided a grain coarsening-resistant copper ingot produced by the method for producing a grain coarsening-resistant copper ingot as described in any one of the examples or implementations of the first aspect of the present application. The cast ingot produced by the production method has the copper content of more than or equal to 99.95 percent, the total content of microalloy elements of less than or equal to 0.045 percent and the total content of other inevitable impurities of less than or equal to 0.005 percent, namely the crystal grain coarsening resistant copper cast ingot provided by the application. The microalloying elements should have the following characteristics: the solid solubility in copper at room temperature is less than or equal to 0.03 percent, and a second phase with the melting point lower than 800 ℃ is not formed in the Cu matrix. The microalloying elements which can be used comprise Ca, Cr, S, Se, Te, Zr or other elements meeting the characteristics, one or more of the elements can be used, and the content of a single microalloying element is less than or equal to 0.045% and more than or equal to 0.0003%.

The invention forms dispersed phase or grain boundary segregation in the copper matrix through micro alloy elements, thereby forming the effect of pinning the grain boundary on the grain boundary of copper grains and inhibiting the growth of recrystallized grains. Meanwhile, the selected element has low solid solubility, so that the influence on the conductivity of copper is small. In addition, the production method provided by the invention can control the content of the added micro-alloy elements to meet the requirement of the required macro-composition, and can also ensure that the micro-alloy elements are uniformly distributed, thereby avoiding secondary recrystallization or abnormal growth of part of crystal grains caused by micro-segregation.

The invention can obviously inhibit the growth of high-temperature recrystallization grains of the pure copper, the pure copper ingot is used for preparing the copper strip, after annealing for 800-10 min, the average grain size of the recrystallization of the finished product is below 50 mu m, and the average grain size of the recrystallization of the conventional pure copper is up to 200 mu m by adopting the same copper strip preparation and high-temperature annealing process. Meanwhile, the soft-state conductivity of the grain coarsening resistant Copper provided by the invention can reach more than 99% IACS (International Annealed Copper Standard), and is close to that of the conventional pure Copper.

Those of skill in the art will appreciate that the various operations, methods, steps in the processes, acts, or solutions discussed in this application can be interchanged, modified, combined, or eliminated. Further, other steps, measures, or schemes in various operations, methods, or flows that have been discussed in this application can be alternated, altered, rearranged, broken down, combined, or deleted. Further, steps, measures, schemes in the prior art having various operations, methods, procedures disclosed in the present application may also be alternated, modified, rearranged, decomposed, combined, or deleted.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

In the description herein, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

It should be understood that, although the steps in the flowcharts of the figures are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and may be performed in other orders unless explicitly stated herein. Moreover, at least a portion of the steps in the flow chart of the figure may include multiple sub-steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, which are not necessarily performed in sequence, but may be performed alternately or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

The foregoing is only a partial embodiment of the present application, and it should be noted that, for those skilled in the art, several modifications and decorations can be made without departing from the principle of the present application, and these modifications and decorations should also be regarded as the protection scope of the present application.

Claims (10)

1. The production method of the crystal grain coarsening resistant copper ingot is characterized by comprising the following steps:

preheating and drying the cathode copper plate with the surface segregation tumor removed to obtain a dried copper plate;

putting the dried copper plate into a smelting furnace for melting, adding the micro-alloy elements and uniformly stirring; the microalloy element is selected from at least one of Ca, Cr, S, Se, Te or Zr, and the percentage content of the microalloy element is less than or equal to 0.045%;

casting operation is carried out by adopting a vertical semi-continuous casting method, the casting speed is 50-100mm/min, and mechanical vibration and inert gas protection are applied to a cast crystallizer to obtain the crystal grain coarsening resistant copper ingot.

2. The method for producing a copper ingot resistant to grain coarsening according to claim 1, wherein the solid solubility of the trace elements in copper at room temperature is 0.03% or less, and the melting point of the second phase formed in the copper matrix is not lower than 800 ℃.

3. The method for producing the copper ingot resistant to grain coarsening according to claim 1, wherein the preheating temperature for preheating and drying is 300-500 ℃.

4. The method for producing the grain coarsening-resistant copper ingot according to claim 1, wherein the copper content of the cathode copper plate is greater than or equal to 99.99% by mass.

5. The method for producing a grain coarsening-resistant copper ingot according to claim 1, wherein the step of melting the dried copper plate in a melting furnace further comprises adding a covering agent to the surface of the molten copper to cover the surface of the molten copper.

6. The method for producing a grain coarsening-resistant copper ingot according to claim 5, wherein the covering agent is a neutral covering agent.

7. The method of producing a grain coarsening-resistant copper ingot according to claim 1, wherein the step of applying mechanical vibration and an inert gas blanket to the casting mold includes: and applying mechanical vibration with preset frequency and preset amplitude to the crystallizer, wherein the preset frequency is 30-300 times/min, and the preset amplitude is 0.1-2.5 mm.

8. The method of producing a grain coarsening-resistant copper ingot according to claim 1, wherein the step of applying mechanical vibration and an inert gas blanket to the casting mold includes: the flow rate of the inert gas is 3-20L/h, and the inert gas is nitrogen and/or argon.

9. A production device of a crystal grain coarsening resistant copper cast ingot is characterized by comprising a crystallizer, a cover body, an air inlet pipe and a casting machine pouring pipe; the cover body is arranged on the top opening of the crystallizer;

the casting machine pouring pipe can extend into the containing cavity of the crystallizer from the pouring port of the cover body, a plurality of air outlets are arranged on the side wall of the pouring port of the cover body, and the air outlets are connected with the air inlet pipe.

10. A grain coarsening resistant copper ingot, which is produced by the production method of the grain coarsening resistant copper ingot according to any one of claims 1 to 8.

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