Method for regulating nickel-phosphorus nano amorphous alloy structure

Abstract

The invention discloses a method for regulating and controlling a nickel-phosphorus nano amorphous alloy structure, which is characterized in that the nickel-phosphorus nano amorphous alloy structure is controlled by regulating and controlling the current density in an electro-deposition process, so that an electro-deposition film has different atomic bulk densities, and the internal structure shows different degrees of non-uniformity; the structural change of the nickel-phosphorus nano amorphous alloy brings changes to the mechanical properties, especially the strength and the toughness of the nickel-phosphorus nano amorphous alloy. The pulse electrodeposition method is adopted, the preparation process is simple and economical, and compared with the prior art, regulation and control of the internal structure of the nano amorphous alloy can be achieved more conveniently, so that the performance can be optimized.

Description

Technical Field

[0001] The invention belongs to the field of amorphous alloys, and in particular relates to a method for regulating the structure of a nickel-phosphorus nano-amorphous alloy. Background Art

[0002] Nanostructured amorphous alloys are a new type of amorphous alloy materials, mainly composed of nanoscale amorphous particles and interfaces connecting particles. Compared with amorphous materials, nano-amorphous has more structural inhomogeneities, which are composed of amorphous interfaces and amorphous clusters. There is a large difference between the density at the amorphous interface and the density between the amorphous clusters, so there are large atomic density fluctuations in the microstructure of nano-amorphous alloys. However, it is difficult to achieve structure-performance regulation of traditional amorphous alloy materials due to their disordered and uniform atomic structure characteristics. In the new nano-amorphous alloy materials, by controlling the density and volume ratio of the introduced interface and the degree of diffusion, the overall atomic structure and density of the material can be regulated, thereby achieving the regulation of the macroscopic properties of disordered uniform amorphous alloy materials such as mechanics, electricity, and magnetism. Therefore, the special structural inhomogeneity characteristics of nano-amorphous alloys make it have a very large potential for structure-performance regulation in amorphous materials.

[0003] So far, the methods for preparing nano-amorphous alloy materials are mainly inert gas condensation, magnetron sputtering and severe plastic deformation. Although relatively successful preparation methods have been developed, these methods have very large limitations in regulating structure-performance. For example, the equipment cost of the inert gas condensation method is high, and the sample size obtained is small; there are oxidation and pore problems at the interface of amorphous particles, which affect the performance of the material. The magnetron sputtering method requires high vacuum equipment and can only prepare thin film samples. The obtained nanostructured amorphous alloy has similar structure and properties to those prepared by the inert gas condensation method. The research on the preparation of nanostructured amorphous alloys by large plastic deformation is still incomplete, and crystallization is also prone to occur during the preparation process. In comparison, pulse electrodeposition is a new low-cost and efficient method for preparing nanostructured amorphous alloys, and it is easy to regulate the structure-performance of the material.

[0004] Therefore, using the parameters of pulse electrodeposition to control the structure and properties of amorphous materials is a very promising method. Summary of the invention

[0005] The purpose of the present invention is to provide a method for regulating the structure of nickel-phosphorus nano-amorphous alloy.

[0006] The technical solution to achieve the purpose of the present invention is:

[0007] In a first aspect, the present invention provides a method for regulating the structure of a nickel-phosphorus nano-amorphous alloy, comprising the following steps:

[0008] The titanium sheet after sandpaper grinding, polishing and degreasing was used as the cathode, the platinum sheet was used as the anode, the nickel-phosphorus system electroplating solution was used as the working solution, and the pulse current deposition method was used. The initial current intensity was set to 5-60 mA / cm 2 The power is on for 10ms, and then the pulse is turned off for 10 to 20ms. The whole process lasts for 120min to 480min to obtain a nano-amorphous alloy coating.

[0009] Preferably, the initial current intensity is 5-15 mA / cm 2 The smaller the initial current density is set, the lower the atomic stacking density inside the coating is, and the better the toughness of the coating is.

[0010] Preferably, the nickel-phosphorus system electroplating solution meets the following conditions: nickel sulfate (NiS04·6H2O) 120-250g / L, nickel chloride (NiCl2·6H2O) 15-30g / L, boric acid (H3BO3) 15-30g / L, phosphorous acid (H3PO3) 3-10g / L, sodium dodecyl sulfate (C 12 H 25 SO4Na)0.15~0.3g / L, pH value 1~2.

[0011] Preferably, the temperature of the deposition process is controlled at 40-70°C.

[0012] Preferably, the composition of the obtained nano amorphous alloy coating is Ni 74.5 P 25.5 .

[0013] Compared with the prior art, the present invention has the following significant advantages: (1) there are no holes inside the coating, the density is high, and the coating quality is high; (2) the preparation process is simple and economical; (3) it is convenient to realize the regulation of the internal structure of the nano-amorphous alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a parameter preparation diagram for regulating nickel-phosphorus nanoamorphous structure.

[0015] Figure 2 This is a graph of the nickel-phosphorus nanoamorphous structure factor S(Q) obtained in Example 1, Example 2, Example 3, Example 4 and Example 5.

[0016] Figure 3 It is the h-ring-directed-field transmission electron microscope (HAADF) test image obtained in Example 1 and Example 5.

[0017] Figure 4 1 is the tensile stress-strain curve obtained in Example 1, Example 3 and Example 5. DETAILED DESCRIPTION

[0018] The present invention will be further described below with reference to the accompanying drawings and examples.

[0019] Example 1

[0020] (1) Prepare the plating solution: NiSO4·6H2O: 200 g / L; NiCl2·6H2O: 25 g / L; H3PO3: 4.6 g / L; H3BO3: 24 g / L; sodium dodecyl sulfate (C 12 H 25 SO4Na): 0.2g / L, pH: 1.5.

[0021] (2) A titanium sheet that has been sanded, polished, and degreased is used as the cathode, and a platinum sheet is used as the anode. The two sheets are arranged parallel and symmetrically in the electroplating solution, and the electrodeposition is carried out in a 50°C water bath environment. Magnetic stirring is turned on during the electrodeposition process.

[0022] (3) The anode and cathode are connected to an electrochemical workstation. Figure 1 is the pulse current gradient control diagram, according to Figure 1 The applied current intensity was 12.5 mA / cm 2 The electrodeposition was carried out for 10 ms, which was the process of forming nano-amorphous particles. Then the pulse was turned off for 15 ms, which was to eliminate the concentration polarization of the cathode end solution and ensure that the deposited coating was uniform and dense. The whole process was repeated for 480 minutes to obtain a nano-sized nickel-phosphorus amorphous alloy coating NG-1.

[0023] (4) The nickel-phosphorus nano-amorphous alloy coating NG-1 was peeled off from its substrate by mechanical peeling. The peeled nickel-phosphorus nano-amorphous alloy coating was ultrasonically cleaned in acetone and dried. The atomic structure of the coating NG-1 was analyzed by high-energy synchrotron X-ray diffraction. The structure factor S(Q) is shown in the figure below. Figure 2 As shown in the figure, the results show that the coating only shows the classic diffuse peak, proving that the structure is completely amorphous. At the same time, it can be seen from the figure that the peak position Q1 of the coating NG-1 is The size of Q1 is positively correlated with the atomic stacking density of the coating.

[0024] (5) The HAADF transmission electron microscope (HAADF) was used to characterize the microstructure of the coating. The HAADF test results are as follows: Figure 3 As shown, the bright and dark areas in the figure represent the obvious structural heterogeneity of high density and low density inside the nickel-phosphorus amorphous alloy coating.

[0025] (6) The mechanical properties curve of the nano-amorphous coating was tested using a micro-tensile device. Figure 4 As shown, Figure 4 The results show that the coating has an elongation of up to 2.34% and a fracture strength of up to 1.87 Gpa.

[0026] Example 2

[0027] Steps (1) to (3) are the same as in Example 1, except that the applied current intensity is 22.5 mA / cm 2 , and obtain a nano-sized nickel-phosphorus amorphous alloy coating NG-2.

[0028] (4) Use high-energy synchrotron X-ray diffraction to analyze the atomic structure of the coating. The structure factor S(Q) is shown in the figure below: Figure 2 As shown in the figure, the results show that the coating only shows the classic diffuse peak, proving that the structure is completely amorphous. At the same time, it can be seen from the figure that the peak position Q1 of the coating is

[0029] Example 3

[0030] Steps (1) to (3) are the same as in Example 1, except that the applied current intensity is 32.5 mA / cm 2 , and obtain a nano-sized nickel-phosphorus amorphous alloy coating NG-3.

[0031] (4) Use high-energy synchrotron X-ray diffraction to analyze the atomic structure of the coating. The structure factor S(Q) is shown in the figure below: Figure 2 As shown in the figure, the results show that the coating only shows the classic diffuse peak, proving that the structure is completely amorphous. At the same time, it can be seen from the figure that the peak position Q1 of the coating is

[0032] (5) The mechanical properties curve of the nano-amorphous coating was tested using a micro-tensile device. Figure 4 As shown, Figure 4 The results show that the coating elongation is 2% and the fracture strength is about 1.80Gpa.

[0033] Example 4

[0034] Steps (1) to (3) are the same as in Example 1, except that the applied current intensity is 42.5 mA / cm 2 , and obtain a nano-sized nickel-phosphorus amorphous alloy coating NG-4.

[0035] (4) Use high-energy synchrotron X-ray diffraction to analyze the atomic structure of the coating. The structure factor S(Q) is shown in the figure below: Figure 2 As shown in the figure, the results show that the coating only shows the classic diffuse peak, proving that the structure is completely amorphous. At the same time, it can be seen from the figure that the peak position Q1 of the coating is

[0036] Example 5

[0037] Steps (1) to (3) are the same as in Example 1, except that the current intensity applied is 47.5 mA / cm 2, and obtain a nano-sized nickel-phosphorus amorphous alloy coating NG-5.

[0038] (4) Use high-energy synchrotron X-ray diffraction to analyze the atomic structure of the coating. The structure factor S(Q) is shown in the figure below: Figure 2 As shown in the figure, the results show that the coating only shows the classic diffuse peak, proving that the structure is completely amorphous. At the same time, it can be seen from the figure that the peak position Q1 of the coating is

[0039] (5) The HAADF transmission electron microscope (HAADF) was used to characterize the microstructure of the coating. The HAADF test results are as follows: Figure 3 As shown, the bright and dark areas in the figure represent the obvious structural heterogeneity of high density and low density inside the nickel-phosphorus amorphous alloy coating.

[0040] (6) The mechanical properties curve of the nano-amorphous coating was tested using a micro-tensile device. Figure 4 As shown, the results show that the coating elongation is 1.77% and the fracture strength is about 1.63Gpa.

Claims

1. A method for regulating the structure of a nickel-phosphorus nano-amorphous alloy, characterized in that: The steps include: The titanium sheet after grinding, polishing and degreasing was used as the cathode, the platinum sheet was used as the anode, the nickel-phosphorus system electroplating solution was used as the working solution, and the pulse current deposition method was used. The initial current intensity was set to 5 ~ 60 mA / cm 2 , the power is on for 10 ms, then the pulse is turned off for 10 to 20 ms. The whole process lasts for 120 min to 480 min to obtain a nano-amorphous alloy coating.

2. The method according to claim 1, characterized in that The initial current intensity is 5 ~ 15mA / cm 2 .

3. The method according to claim 1, characterized in that The nickel-phosphorus system electroplating solution meets the following conditions: nickel sulfate 120 ~ 250 g / L, nickel chloride 15 ~ 30 g / L, boric acid 15 ~ 30 g / L, phosphorous acid 3 ~ 10 g / L, sodium dodecyl sulfate 0.15 ~ 0.3 g / L, pH value 1 ~ 2.

4. The method according to claim 1, characterized in that The temperature of the deposition process was controlled at 40 ~ 70 °C.

5. The method according to claim 1, characterized in that The composition of the obtained nano-amorphous alloy coating is Ni 74.5 P 25.5 .

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