阅读说明：本技术 铝合金相的立体形态提取方法 (Method for extracting three-dimensional shape of aluminum alloy phase ) 是由 王东涛 长海博文 张孝足 张海涛 李新中 秦简 董其鹏 于 2019-09-27 设计创作，主要内容包括：本发明揭示了一种铝合金相的立体形态提取方法,首先根据需要切取一定量的铝合金试样,打磨表面并超声清洗处理,接下来配制一定浓度的中性水溶液,铝合金试样作为阳极材料用导线与直流电源正极连接后放入中性水溶液中进行电解,将铝基体溶解而铝合金中的合金相保留在中性水溶液中沉降在烧杯底部,通过过滤、清洗、离心分离、干燥处理得到合金相样品,即可进行合金相的完整三维形貌观察。本发明可完整有效的提取铝合金中各种合金相,包括强酸强碱水溶液无法完整提取的化学计量比可变的铝合金相,从而可以全面高效的对其进行三维形貌观察及微观研究。(the invention discloses a method for extracting a three-dimensional shape of an aluminum alloy phase, which comprises the steps of cutting a certain amount of an aluminum alloy sample according to requirements, polishing the surface of the aluminum alloy sample, carrying out ultrasonic cleaning treatment, preparing a neutral aqueous solution with a certain concentration, connecting the aluminum alloy sample serving as an anode material with a direct-current power supply positive electrode by using a lead, then putting the aluminum alloy sample into the neutral aqueous solution for electrolysis, dissolving an aluminum matrix, retaining an alloy phase in the aluminum alloy in the neutral aqueous solution, settling the alloy phase at the bottom of a beaker, filtering, cleaning, carrying out centrifugal separation, and carrying out drying treatment to obtain an alloy phase sample, thus carrying out complete three-dimensional shape observation on. The method can completely and effectively extract various alloy phases in the aluminum alloy, including the aluminum alloy phase with variable stoichiometric ratio which can not be completely extracted by the strong acid and strong alkali aqueous solution, thereby comprehensively and efficiently carrying out three-dimensional appearance observation and microscopic research on the aluminum alloy.)

1. A method for extracting a three-dimensional shape of an aluminum alloy phase, wherein the aluminum alloy phase comprises a multi-component intermetallic compound with a variable stoichiometric ratio and a single-phase and/or multi-component alloy phase with a fixed stoichiometric ratio, which are separated from a liquid phase in the solidification process of the aluminum alloy, and the method comprises the following steps:

S1: cutting a certain amount of aluminum alloy sample, polishing the surface and carrying out ultrasonic cleaning treatment;

s2: preparing a neutral electrolyte aqueous solution with a certain concentration and heating;

S3: connecting a sample serving as an anode material with a positive electrode of a direct-current power supply by using a lead, and then putting the sample into the neutral electrolyte aqueous solution for electrolysis, immersing the aluminum alloy sample into electrolyte, and putting a connecting part and a lead wire in the air;

S4: after the electrolysis is finished, filtering residues in the electrolyzed solution by using a screen mesh, and filtering by using a filtering device to obtain an aluminum alloy phase remained on the filter paper;

s5: mixing the filtered aluminum alloy phase with Al (OH) by a centrifuge₃Performing centrifugal separation on the mixture, and removing upper-layer turbid liquid to obtain a bottom aluminum alloy phase;

S6: carrying out ultrasonic cleaning on the separated aluminum alloy phase to remove impurities attached to the surface of the phase;

S7: and putting the aluminum alloy phase obtained by cleaning into a vacuum drying oven for drying treatment to obtain the aluminum alloy phase capable of carrying out three-dimensional morphology observation under a scanning electron microscope.

2. the method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein the aluminum is: the aluminum alloy phase comprises a multi-element intermetallic compound with variable stoichiometric ratio precipitated from a liquid phase during the solidification process of the aluminum alloy, and the composition elements of the multi-element intermetallic compound comprise Al element and one or more selected from other elements of Fe, Si, Cu, Ni, Ti, Mn, Ca, V, Cr, Co, Zr, Sr and Y.

3. the method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: the alloy phase comprises a fixed stoichiometric ratio of intermetallic compounds and non-metallic phases precipitated from the liquid phase during solidification of the aluminum alloy, includingMg₂Si and Si phases.

4. the method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: the alloy phase comprises a unary phase, a binary phase, a ternary phase, a quaternary phase and a quinary phase.

5. The method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: the sample is sheet-shaped, and the thickness of the sample is less than or equal to 15 mm.

6. The method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: the neutral electrolyte aqueous solution in S2 is selected from NaCl, KCl and CaCl₂one of the solutions has a concentration of 0.001-15% and a temperature of 40-100 ℃.

7. The method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 4, wherein: in the step S2, an electrochemical electrolysis means is used for dissolving the aluminum alloy matrix, the extraction liquid of the aluminum alloy phase is a neutral electrolyte aqueous solution, and the solute concentration of the extraction liquid of the first-order phase is 10-15%; the solute concentration of the binary phase and the ternary phase is 5-10%, and the solute concentration of the quaternary phase and the quinary phase is 0.001-5%.

8. The method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: the set voltage value of the direct current power supply in the S3 is 8-40V, the current value is 1-15A, a cathode material during electrolysis is connected with a negative electrode of the power supply and then is immersed in a neutral electrolyte aqueous solution, the cathode material is inert metal, and a connecting lead of an aluminum alloy sample and a positive electrode of the power supply is a Cu, Zn or Fe wire rod.

9. The method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: and in the S5, the centrifugation parameter is 3000-20000 r/min, the centrifugation time is 7-15 min, and the repeated centrifugation time is not less than 3 times.

10. The method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: the ultrasonic frequency in the S6 is 20000-60000 Hz, the time is 5-15 min, and the repeated ultrasonic cleaning is not less than 3 times.

11. The method for extracting a three-dimensional morphology of an aluminum alloy phase according to claim 1, wherein: and the drying temperature in the S7 is 50-80 ℃, and the drying time is 40-200 min.

Technical Field

The invention relates to the field of aluminum alloy materials, in particular to a method for extracting a three-dimensional shape of an aluminum alloy phase.

background

The aluminum alloy has the advantages of low density, high specific strength, corrosion resistance and the like, and is widely applied to the industries of aerospace, transportation, electronic products and the like. Aluminum alloys contain a large number of unstable primary phases and intermetallic compounds, which have a significant influence on the material properties. However, the three-dimensional morphology of the aluminum alloy phase is not well studied at present due to the lack of simple and efficient extraction means.

Chinese patent CN104928519A discloses a method for extracting a second phase from an Al-Mg-Si series aluminum alloy, which mainly comprises the steps of preparing the aluminum alloy into powder, corroding an aluminum alloy matrix by using enough 4-6% NaOH solution, and filtering to obtain the second phase. However, the NaOH solution belongs to strong alkali, which can corrode and destroy the structure of the intermetallic compound with variable stoichiometric ratio in the aluminum alloy, and the method is not suitable for extracting various aluminum alloy phases with variable stoichiometric ratio. And the use of strong acid and strong base has poor operation safety, environmental pollution and complex waste liquid treatment procedure.

Chinese invention patent CN101760622A discloses a method for extracting Mg2Si crystal from high silicon magnesium alloy, which comprises processing magnesium alloy into particles by milling machine, then putting into saturated saline water containing ammonium ions and chloride ions for corrosion extraction to obtain Mg₂And (4) Si crystal. The method can obtain Si and Mg₂si crystals are intact or flawed, and for extraction of variable stoichiometry intermetallics, the process also destroys the structural integrity of the intermetallics. The method uses strong alkaline solution to extract the compound, and has the problems of poor operation safety, environmental pollution, complex waste liquid treatment procedure and the like.

Disclosure of Invention

aiming at the defects and shortcomings of the existing aluminum alloy phase three-dimensional shape extraction technology, the invention provides the aluminum alloy phase three-dimensional shape extraction method, which is used for stripping an aluminum matrix and simultaneously keeping a complete aluminum alloy phase by a simple and efficient neutral aqueous solution environment and an electrolysis means, and has important significance for the research on the three-dimensional shape and growth of different types of aluminum alloy phases.

In order to achieve the purpose, the invention provides the following technical scheme: a method for extracting the three-dimensional shape of an aluminum alloy phase is characterized by comprising the following steps:

S1: cutting a certain amount of aluminum alloy sample, polishing the surface and carrying out ultrasonic cleaning treatment;

s2: preparing a neutral electrolyte aqueous solution with a certain concentration and heating;

S3: connecting the sample as anode material with the positive pole of DC power supply via wire, electrolyzing in the water solution of neutral electrolyte,

s4: after the electrolysis is finished, filtering residues in the electrolyzed solution by using a screen mesh, and filtering by using a filtering device to obtain an aluminum alloy phase remained on the filter paper;

s5: mixing the filtered aluminum alloy phase with Al (OH) by a centrifuge₃Performing centrifugal separation on the mixture, and removing upper-layer turbid liquid to obtain a bottom aluminum alloy phase;

S6: carrying out ultrasonic cleaning on the separated aluminum alloy phase to remove impurities attached to the surface of the phase;

s7: and putting the aluminum alloy phase obtained by cleaning into a vacuum drying oven for drying treatment to obtain the aluminum alloy phase capable of carrying out three-dimensional morphology observation under a scanning electron microscope.

preferably, the aluminum alloy phase comprises a multi-component intermetallic compound with variable stoichiometric ratio precipitated from the liquid phase during the solidification of the aluminum alloy, and the component elements of the multi-component intermetallic compound comprise Al element and one or more selected from other elements Fe, Si, Cu, Ni, Ti, Mn, Ca, V, Cr, Co, Zr, Sr and Y.

Preferably, the alloy phases include a fixed stoichiometric ratio of intermetallic and non-metallic phases, including Mg2Si and Si phases, precipitated from the liquid phase during solidification of the aluminum alloy.

preferably, the alloy phases include a unary phase, a binary phase, a ternary phase, a quaternary phase, and a quinary phase.

preferably, the sample in S1 is in the form of a sheet with a thickness of 15mm or less.

preferentially, an electrochemical electrolysis means is used for dissolving the aluminum alloy matrix in S2, the extraction liquid of the aluminum alloy phase is a neutral electrolyte aqueous solution, and the solute concentration of the extraction liquid of the first phase is 10-15%; the solute concentration of the binary phase and the ternary phase is 5-10%, and the solute concentration of the quaternary phase and the quinary phase is 0.001-5%.

Preferably, the neutral electrolyte aqueous solution in S2 is selected from NaCl, KCl, CaCl₂one of the solutions has a concentration of 0.001-15% and a temperature of 40-100 ℃.

preferably, the dc power supply in S3 has a set voltage value of 8-40V and a current value of 1-15A, and the cathode material during electrolysis is connected to the negative electrode of the power supply and then immersed in the neutral electrolyte aqueous solution, wherein the cathode material is an inert metal.

preferably, the centrifugation parameter in the S5 is 3000-20000 r/min, the centrifugation time is 7-15 min, and the repeated centrifugation times are not less than 3.

preferentially, the ultrasonic frequency in the S6 is 20000-60000 Hz, the time is 5-15 min, and the repeated ultrasonic cleaning is not less than 3 times.

preferably, the drying temperature in the step S7 is 50-80 ℃, and the drying time is 40-200 min.

The method can completely and effectively extract various alloy phases in the aluminum alloy, including the aluminum alloy phase with variable stoichiometric ratio which can not be completely extracted by the strong acid and strong alkali aqueous solution, thereby comprehensively and efficiently carrying out three-dimensional appearance observation and microscopic research on the aluminum alloy.

Drawings

FIG. 1 is a microstructure of an extracted Fe-containing phase according to the present invention;

FIG. 2 is a microstructure and energy spectrum of the Fe-containing phase extracted in example 1;

FIG. 3 is TiAl extracted from example 2₃Phase microscopic shapeAppearance and energy spectrogram;

FIG. 4 is a micro-topography and energy spectrum of the extracted Si phase of example 3.

Detailed Description

The technical solution of the embodiment of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention.

the invention discloses a method for extracting the three-dimensional shape of an aluminum alloy phase, wherein the aluminum alloy phase comprises intermetallic compounds with variable stoichiometric ratios formed by Al, Fe, Cu, Ni, Ti and the like precipitated from a liquid phase in the aluminum alloy solidification process, and Mg precipitated from the liquid phase in the aluminum alloy solidification process₂The intermetallic compound and the non-metallic phase with fixed stoichiometric ratio of Si, etc. the number of different element components of the aluminum alloy phase comprises one element, two elements, three elements, four elements and five elements. The specific extraction method comprises the following steps:

S1: cutting a certain amount of sheet-shaped aluminum alloy sample, wherein the thickness of the sample is less than or equal to 15mm, polishing the surface of the sample by using sand paper, and ultrasonically cleaning the sample;

S2: preparing a neutral electrolyte aqueous solution with the concentration of 0.001-15% by using deionized water as an extraction liquid, heating the extraction liquid to 40-100 ℃ in a water bath heating mode, and dissolving the aluminum alloy matrix by using an electrochemical electrolysis means, wherein the neutral electrolyte aqueous solution is selected from NaCl, KCl and CaCl₂The concentration of the neutral electrolyte aqueous solution is different according to different aluminum alloy phase element phases, specifically, the solute concentration of the electrolyte aqueous solution of the phase element is 10-15%; the solute concentration of the binary and ternary phase extraction liquid is 5-10%, and the solute concentration of the quaternary and quinary phase extraction liquid is 0.001-5%.

S3: connecting a sample as an anode material with a direct current power supply anode with a voltage value of 8-40V and a current value of 1-15A by using a lead, putting the sample into the neutral electrolyte aqueous solution for electrolysis, connecting a cathode material with a power supply cathode, immersing the cathode material into the neutral electrolyte aqueous solution, switching on the power supply, adjusting the voltage and the current value, starting decomposition of the aluminum alloy matrix, and settling intermetallic compounds; the aluminum alloy sample and the positive electrode connecting lead of the power supply are wires of Cu, Zn, Fe and the like, the cathode material is inert metal, the aluminum alloy sample is immersed in electrolyte in an electrolysis mode, and the connecting part and the lead are placed in the air.

s4: after the electrolysis is finished, filtering residues in the electrolyzed solution by using a screen with the aperture of 20-40 meshes, and filtering by using a filtering device to obtain intermetallic compounds remained on the filter paper;

S5: mixing the filtered aluminum alloy phase with Al (OH) by a centrifuge₃centrifuging the mixture, wherein the centrifuging parameter is 3000-20000 r/min, the centrifuging time is 7-15 min, the repeated centrifuging times are not less than 3 times, and removing the upper-layer turbid liquid after centrifuging to obtain a bottom aluminum alloy phase;

S6: putting the separated aluminum alloy phase into alcohol, and ultrasonically cleaning impurities attached to the surface of the phase, wherein the ultrasonic frequency is 20000-60000 Hz, the time is 5-15 min, and the number of repeated ultrasonic cleaning is not less than 3;

S7: and (3) drying the aluminum alloy phase obtained by cleaning in a vacuum drying oven at the temperature of 50-80 ℃ for 40-200 min, and observing the three-dimensional morphology under a scanning electron microscope, wherein as shown in figure 1, a microstructure diagram of the phase containing Fe extracted by the method is shown.

the following describes the implementation of the present invention by way of specific examples 1 to 3.