阅读说明：本技术 一种高钴轴承钢透镜试样的制备方法 (Preparation method of high-cobalt bearing steel lens sample ) 是由 李绍宏 何文超 魏鑫鸿 郭涵 王永恒 张旭 李俊 于 2020-12-11 设计创作，主要内容包括：本发明公开一种高钴轴承钢透镜试样的制备方法,属于材料分析测试技术领域。本发明所述方法为：使用线切割机在试验钢中切取薄片状透射电镜原始试样；将得到的薄片在不同目数的水磨砂纸中逐级打磨并控制减薄,使用透射电镜冲孔器冲得标准样；将标准样进行电解双喷穿孔制作薄区；穿孔后的试样在无水乙醇中清洗两遍后干燥即可。本发明使用的电解双喷液在失效后仍可以回收使用,将失效旧电解液按照一定比例添加进新配的双喷电解液中,依然可以制备出薄区面积大、质量稳定的透镜试样；不仅节约了电解液的使用,同时也对环境保护起到积极作用。(The invention discloses a preparation method of a high-cobalt bearing steel lens sample, and belongs to the technical field of material analysis and test. The method comprises the following steps: cutting a thin-sheet transmission electron microscope original sample in test steel by using a wire cutting machine; gradually polishing the obtained sheet in water-milled sand paper with different meshes, controlling the thinning, and punching a standard sample by using a transmission electron microscope puncher; carrying out electrolytic double-spraying perforation on the standard sample to manufacture a thin area; and (4) washing the punched sample twice in absolute ethyl alcohol and drying. The electrolytic double-spraying liquid used in the invention can be recycled after failure, and the failed old electrolyte is added into the newly-prepared double-spraying electrolyte according to a certain proportion, so that a lens sample with large thin area and stable quality can be prepared; not only saves the use of electrolyte, but also plays a positive role in environmental protection.)

1. The preparation method of the high-cobalt bearing steel lens sample is characterized by comprising the following steps:

(1) cutting a thin-sheet transmission electron microscope original sample in test steel by using a wire cutting machine;

(2) gradually polishing the slices obtained in the step (1) in water-milled sand paper with different meshes and controlling the thinning;

(3) punching the sheet obtained in the step (2) by using a transmission electron microscope puncher to obtain a standard sample;

(4) carrying out electrolytic double-jet perforation on the standard sample in the step (3) to manufacture a thin area, wherein the double-jet parameters are that the temperature is-15 ℃, the voltage is 32V, and the jet beam current is 35; in the double-spraying process, voltage and jet beam current need to be finely adjusted, and the fine adjustment parameter range is as follows: the voltage is 32 +/-1 v, and the beam current is 35 +/-2, so that the current is stabilized at 30 +/-5 mA.

2. The method for preparing a high cobalt bearing steel lens sample according to claim 1, wherein: the thickness of the thin sheet cut out in step (1) using wire cutting was 500. mu.m.

3. The method for preparing a high cobalt bearing steel lens sample according to claim 1, wherein: the sand paper used in the step (2) has the mesh numbers of 600, 800, 1000, 1500 and 2000 meshes respectively.

4. The method for preparing a high cobalt bearing steel lens sample according to claim 1, wherein: and (3) controlling thinning in the step (2), namely, when one surface of the sample is polished to be bright and free from scratches, taking down the sample, polishing the other surface of the sample, controlling thinning, reducing the sample to be 40 +/-2 mu m, taking down and cleaning.

5. The method for preparing a high cobalt bearing steel lens sample according to claim 1, wherein: in the step (4), the electrolyte for electrolytic double-spraying is as follows: 8% perchloric acid +92% absolute ethanol solution.

6. The method for preparing a high cobalt bearing steel lens sample according to claim 1, wherein: and (4) recovering the double-spraying liquid after the double-spraying liquid in the step (3) is invalid, wherein the volume ratio of the recovered double-spraying liquid to the newly-prepared double-spraying liquid is 1: 2.

Technical Field

The invention relates to a preparation method of a high-cobalt bearing steel lens sample, belonging to the technical field of material analysis and test.

Background

The transmission electron microscope is an effective tool for observing the internal structure of the material and determining the phase structure, and has important value in the research of steel materials. However, the preparation of the transmission electron microscope sample is harsh, and the influence factors needing to be controlled in the sample preparation process are more, so that the preparation of the sample is always a difficult problem which troubles the testing of the steel material lens.

The low-carbon alloy steel with higher cobalt content has the characteristics of high hardness, good corrosion resistance and the like. The edge of the high-cobalt steel lens sample is easy to curl and tilt in the grinding and thinning process, so that the subsequent grinding process is influenced, the thickness of the standard sample after punching is uneven, stress corrosion is easy to generate in the double-spraying process, and the effect of the thin area of the sample is poor. Meanwhile, the setting of parameters such as temperature, voltage, jet beam current and the like during double-jet all have important influence on the quality of the sample. After multiple double-spraying, the concentration of the corrosive liquid is reduced, so that the double-spraying process cannot be continued, and the double-spraying liquid needs to be replaced. The double-spraying liquid used for preparing the lens sample is mostly an alcoholic solution of strong acid, and the solution can cause harm to the environment when being recovered and treated improperly.

For low-carbon high-alloy steel iron materials, a lens sample prepared by using an electrolysis double-spraying method is usually high in thickness, and a high-resolution lattice phase cannot be obtained basically in the testing process, although the lens sample with a better thin area can be prepared by using an ion thinning method, the sample preparation consumes long time, and the efficiency is low; the invention provides a simple, efficient, stable and environment-friendly method for preparing a high-cobalt steel transmission electron microscope sample, aiming at the problem of preparing a low-carbon high-cobalt bearing steel transmission electron microscope sample.

Disclosure of Invention

The invention aims to provide a preparation method of a high-cobalt bearing steel transmission electron microscope sample, which has the advantages of simple process, high efficiency, more thin areas and good quality of the obtained sample, and can be used for quickly and massively preparing a lens sample; the sample prepared by the method can be used for observing common tissue morphology and phase structure and high-resolution lattice image of the tissue, and the preparation process specifically comprises the following steps:

(1) thin-sheet transmission electron microscope raw samples were cut in test steel using a wire cutter.

(2) And (3) gradually polishing the slices obtained in the step (1) in water-milled sand paper with different meshes and controlling the thinning.

(3) And (3) punching the sheet obtained in the step (2) into a standard sample by using a transmission electron microscope puncher.

(4) Carrying out electrolytic double-jet perforation on the standard sample in the step (3) to manufacture a thin area, wherein the double-jet parameters are that the temperature is-15 ℃, the voltage is 32V, and the jet beam current is 35; in the double-spraying process, voltage and jet beam current need to be finely adjusted, and the fine adjustment parameter range is as follows: the voltage is 32 +/-1 v, and the beam current is 35 +/-2, so that the current is stabilized at 30 +/-5 mA.

Preferably, the thickness of the thin slices cut out using wire cutting in step (1) of the present invention is 500. mu.m.

Preferably, the number of the sandpaper used in step (2) of the present invention is 600, 800, 1000, 1500, 2000 meshes.

Preferably, in the step (2) of the present invention, the thinning is controlled by taking off the sample and polishing the other side of the sample when one side of the sample is polished to be bright and free from scratches, and the sample is taken off and washed down to 40 ± 2 μm.

Preferably, the electrolyte for electrolytic double-spraying in step (4) of the present invention is: 8% perchloric acid +92% absolute ethanol solution.

Preferably, in the step (3) of the invention, the double spray liquid can be recycled after being failed, and the volume ratio of the recovered double spray liquid to the newly prepared double spray liquid is 1: 2.

All percentages in the present invention are mass percentages unless otherwise specified.

The invention has the beneficial effects that:

(1) the invention adopts manual grinding and electrolytic double-spraying to prepare the high-cobalt bearing steel transmission electron microscope sample; compared with an ion thinning method, the method has the advantages of simple process and high efficiency; compared with the common electrolysis double-spraying method, the method has the advantages of large area of the thin area of the sample, stable quality and the like.

(2) The electrolytic double-spraying liquid used in the invention can be recycled after failure, and the failed old electrolyte is added into the newly-prepared double-spraying electrolyte according to a certain proportion, so that a lens sample with large thin area and stable quality can be prepared; not only saves the use of electrolyte, but also plays a positive role in environmental protection.

Drawings

FIG. 1 is a photograph of the sample obtained in example 1 taken by transmission electron microscopy₆C-type carbide high-resolution lattice image pictures;

FIG. 2 is a photograph of M taken under a transmission electron microscope in example 1₂C-type carbide high-resolution lattice image pictures;

FIG. 3 is a photograph of austenite taken under a transmission electron microscope in example 1;

figure 4 shows the corresponding austenite and martensite electron diffraction patterns for example 1.

Detailed Description

The invention will be described in more detail with reference to the following figures and examples, but the scope of the invention is not limited thereto.

Table 1 shows the steel composition (wt%)

TABLE 1

C

Cr

Mo

Co

Ni

V

W

Fe

0.1～0.15

13～15

4～5

12～13

1.5～2.5

0.5～1

0.5～1

Bal

Example 1

The preparation method of the high-cobalt bearing steel transmission electron microscope sample specifically comprises the following steps:

(1) a sheet sample having a gauge of 10X 10mm and a thickness of 500 μm was cut out of the test steel using a wire cutter.

(2) And (2) adhering the sample obtained in the step (1) on a flat iron block by using 502 glue, and polishing the sample by using 600, 800, 1000, 1500 and 2000-mesh water-mill sandpaper step by step until the polished surface of the sample is smooth and has no scratch.

(3) And (3) immersing the iron block adhered with the thin sheet in the step (2) in acetone, ultrasonically vibrating until the thin sheet naturally falls off, taking out and cleaning.

(4) And (4) adhering the slice sample obtained in the step (3) to the iron block again, polishing the non-polished surface by the same method, controlling the thinning until the thickness is reduced to about 40 mu m, taking down the sample, cleaning and drying.

(5) Punching the sample obtained in the step (4) in a puncher to obtain a standard sample with the diameter of 3 mm;

(6) and (3) carrying out electrolytic double-spraying perforation on the standard sample obtained in the step (5) in a double-spraying thinning instrument with the model of Tenu Pol-5, and manufacturing an observation thin area.

The formula of the double-spraying liquid in the step (6) is as follows: 8% perchloric acid +92% absolute ethanol solution.

And the parameters of electrolysis and double spraying in the step (6) are as follows: the temperature is-15 ℃, the voltage is 32V, the jet beam current is 35, the current is stabilized at about 30mA, and the perforation time is kept between 45 s and 60 s.

(7) Cleaning the sample obtained in the step (6) twice in absolute ethyl alcohol, and then drying and storing; after about 30 lens standard samples are sprayed on every 1.5 liters of double-spraying liquid, the double-spraying liquid needs to be replaced, the failed old electrolyte can be recycled, and the volume ratio of the recovered double-spraying liquid to the newly-prepared double-spraying liquid is 1: 2.

FIG. 1 is a transmission electron microscope image of M of the sample obtained in example 1₆C-type carbide high-resolution lattice image pictures; FIG. 2 is a photograph of the sample obtained in example 1 taken under a transmission electron microscope₂C-type carbide high-resolution lattice image pictures; FIG. 3 is an austenite picture of the sample obtained in example 1 taken under a transmission electron microscope; FIG. 4 shows the corresponding austenite and martensite electron diffraction patterns for the sample obtained in example 1. It can be seen from the figure that the high-resolution lattice image of the transmission sample prepared by the embodiment is uniform, the diffraction pattern is clear, and compared with the common electrolytic double-spraying sample, the thin area is larger, the required field of view is more conveniently found, and the shooting quality is stable.