阅读说明：本技术 一种金相腐蚀液及其制备方法 (Metallographic corrosive liquid and preparation method thereof ) 是由 谭元标 杨亚 向嵩 杨秋月 张文玮 于 2020-07-07 设计创作，主要内容包括：本申请公开了一种金相腐蚀液及其制备方法,其中金相腐蚀液按体积分数百分比,包括8～12％的氢氟酸溶液,40～50％的硝酸溶液,4～8％的盐酸溶液,余量为水。本申请的一个技术效果在于,本申请的金相腐蚀液可以使热变形中没有发生再结晶的晶粒的晶界清晰,容易辨认,有利于晶粒尺寸的测量。(The application discloses a metallographic etchant and a preparation method thereof, wherein the metallographic etchant comprises 8-12% of hydrofluoric acid solution, 40-50% of nitric acid solution, 4-8% of hydrochloric acid solution and the balance of water according to a percentage by volume. The metallographic etchant has the advantages that the grain boundary of grains which are not recrystallized in thermal deformation can be clear, the grains can be easily identified, and the grain size measurement is facilitated.)

1. The metallographic etchant is characterized by comprising, by volume percentage, 8-12% of hydrofluoric acid solution, 40-50% of nitric acid solution, 4-8% of hydrochloric acid solution and the balance of water.

2. The metallographic etchant according to claim 1, wherein the hydrofluoric acid solution has a concentration of 40% by mass of hydrofluoric acid.

3. The metallographic etchant according to claim 1, wherein the nitric acid solution has a concentration of 65% by mass of nitric acid.

4. The metallographic etchant according to claim 1, wherein the hydrochloric acid solution contains hydrochloric acid in an amount of 36 to 38% by mass.

5. A method for preparing a metallographic etchant according to any one of claims 1 to 4, comprising the steps of:

provided in volume fractions: 8-12% of hydrofluoric acid solution, 40-50% of nitric acid solution, 4-8% of hydrochloric acid solution and the balance of water;

putting water into a plastic container, sequentially adding hydrofluoric acid solution, nitric acid solution and hydrochloric acid solution, and uniformly mixing.

Technical Field

The application belongs to the technical field of metallographic corrosion of metal materials, and particularly relates to a metallographic corrosive liquid and a preparation method thereof.

Background

Zirconium alloys have properties such as high strength, high corrosion resistance, high melting point, and good plasticity, and are therefore used in important fields such as aerospace, nuclear reactions, military industry, atomic energy, and the like. In these fields, the mechanical properties of zirconium alloys are required to be high, and the mechanical properties of zirconium alloys significantly depend on the microstructure formed by the hot working process of zirconium alloys. Therefore, the research on the hot working behavior of the zirconium alloy is of great significance. In the process of researching the thermal deformation of the zirconium alloy, different microstructure structures are often formed due to different components and thermal deformation processes of the alloy, and the different microstructure structures determine that the alloy has different physical, chemical and mechanical properties. Therefore, in order to obtain a zirconium alloy with good mechanical properties, the optical metallographic structure of the microstructure of the zirconium alloy after thermal deformation needs to be observed so as to adjust the thermal processing parameters of the zirconium alloy in time to obtain the required microstructure.

Generally, the metallographic etchant for zirconium alloy consists of hydrofluoric acid, nitric acid, water and the like, and the volume percentage ratio of the metallographic etchant to the hydrofluoric acid is HF: HNO₃：H₂O is 10%: 45%: 45 percent. The metallographic corrosive liquid is adopted to corrode zirconium alloy, particularly, a zirconium alloy sample which is not recrystallized in thermal deformation often forms a white thin film pollution layer which is difficult to remove on the surface of the metallographic sample, when the structure on the surface of the sample is observed under a metallographic microscope, the surface is blackened, the grain boundary is blurred, adverse effects are generated on the observation and the identification of the metallographic structure, and the measurement of the grain size is not facilitated.

Therefore, there is a need for an improved metallographic etchant.

Disclosure of Invention

An object of the application is to provide a new technical scheme of a metallographic etchant.

According to one aspect of the application, the application provides a metallographic etchant which comprises 8-12% of hydrofluoric acid solution, 40-50% of nitric acid solution, 4-8% of hydrochloric acid solution and the balance of water in percentage by volume.

Optionally, the hydrofluoric acid solution has a concentration of hydrofluoric acid of 40% by mass.

Optionally, the mass percentage concentration of the nitric acid in the nitric acid solution is 65%.

Optionally, the mass percentage concentration of the hydrochloric acid in the hydrochloric acid solution is 36-38%.

According to another aspect of the application, the application also provides a preparation method of the metallographic etchant, which comprises the following steps:

provided in volume fractions: 8-12% of hydrofluoric acid solution, 40-50% of nitric acid solution, 4-8% of hydrochloric acid solution and the balance of water;

putting water into a plastic container, sequentially adding hydrofluoric acid solution, nitric acid solution and hydrochloric acid solution, and uniformly mixing.

The metallographic etchant has the advantages that the grain boundary of grains which are not recrystallized in thermal deformation can be clear, the grains can be easily identified, and the grain size measurement is facilitated.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

FIG. 1 is a schematic diagram of the use effect of embodiment 1 of the present application;

FIG. 2 is a schematic diagram of the application effect of embodiment 2 of the present application;

FIG. 3 is a schematic diagram of the application effect of embodiment 3 of the present application;

fig. 4 is a schematic diagram showing the effect of comparative example 1 of the present application.

Detailed Description

Embodiments of the present application will be described in detail with reference to the drawings and examples, so that how to implement technical means to solve technical problems and achieve technical effects of the present application can be fully understood and implemented.