A Metallographic Corrosion Method for Rapidly Displaying Grain Boundaries of Special Steel

Abstract

The invention relates to a metallographic corrosion method for rapidly displaying grain boundaries of special steel, belonging to the technical field of metallographic detection. In order to solve the problems of the existing metallographic corrosion method, such as complex procedures, long detection period, and potential safety hazards in the etchant, the present invention provides a metallographic corrosion method for quickly displaying the grain boundaries of special steel, including preparing dinitrophenol etchant, special steel Grinding and polishing the sample, completely immersing the polished surface of the sample in dinitrophenol etchant at room temperature, spraying and cleaning with ethanol after corrosion for 5 to 10 seconds, and observing the grain boundary under a metallographic microscope after drying. The metallographic corrosion method provided by the invention has short corrosion time, simple steps, convenient operation, and can quickly provide metallographic detection results. The present invention uses dinitrophenol as the corrosive agent to ensure that the production inspection is not affected by the increase of the dangerous level of the picric acid medicine. The preparation and use of dinitrophenol etchant are safe and convenient, and the special steel can obtain a clear metallographic structure after corrosion, and the grain boundaries are clear and continuous.

Description

technical field

[0001] The invention belongs to the technical field of metallographic detection, in particular to a metallographic corrosion method for rapidly displaying special steel grain boundaries. Background technique

[0002] Metallographic detection is an important means for metal material research or production enterprises to grasp the product structure and grain size in time during the production process. Through the metallographic detection results, the quality problems in the production process can be analyzed, and the process parameters can be changed and optimized. Control and improve product quality. Metallographic corrosion is an important part of metallographic detection. Only by using a suitable etchant to corrode a clear metallographic structure and grain boundary can the observation of the metallographic structure and the analysis of the grain size and the content of each phase be carried out, so as to accurately determine the heat treatment. Whether the...

Examples

Embodiment 1

[0023] A metallographic corrosion method for rapidly displaying special steel grain boundaries, comprising the following steps:

[0024] Step 1, prepare dinitrophenol corrosion agent;

[0025] Step 2. Roughly grind the surface of the special steel sample to remove the rust layer on the surface. The coarsely ground sample is finely ground on sandpaper; the finely ground sample surface is polished to obtain a bright and scratch-free surface. sample surface;

[0026] Step 3. At room temperature, completely immerse the polished surface of the special steel sample obtained in Step 2 in the dinitrophenol etchant prepared in Step 1. Rinse the corroded sample surface with ethanol after 5 to 10 seconds of corrosion, and place it in the oven after drying. The grain boundaries were observed under a metallographic microscope.

Embodiment 2

[0028] A metallographic corrosion method for rapidly displaying special steel grain boundaries, comprising the following steps:

[0029] Step 1. Prepare dinitrophenol etchant; at room temperature, thoroughly mix analytically pure grade phenol with a mass volume ratio of 5g:5mL and nitric acid with a mass concentration of 65%, and then obtain dinitrophenol etchant in 3-5 minutes.

[0030] Step 2. Roughly grind the surface of the special steel sample to remove the rust layer on the surface. The coarsely ground sample is finely ground on sandpaper; the finely ground sample surface is polished to obtain a bright and scratch-free surface. sample surface;

[0031] Step 3. At room temperature, completely immerse the polished surface of the special steel sample obtained in Step 2 in the dinitrophenol etchant prepared in Step 1. Rinse the corroded sample surface with ethanol after 5 to 10 seconds of corrosion, and place it in the oven after drying. The grain boundaries were observed u...

Embodiment 3

[0034] A metallographic corrosion method for rapidly displaying special steel grain boundaries, comprising the following steps:

[0035] Step 1: Prepare dinitrophenol etchant; at room temperature, thoroughly mix analytically pure grade phenol with a mass volume ratio of 5g:5mL and nitric acid with a mass concentration of 65% to obtain dinitrophenol etchant.

[0036] Step 2. Roughly grind the surface of the special steel sample to remove the rust layer on the surface. The coarsely ground sample is finely ground on sandpaper; the finely ground sample surface is polished to obtain a bright and scratch-free surface. sample surface;

[0037] Step 3. At room temperature, completely immerse the polished surface of the special steel sample obtained in Step 2 in the dinitrophenol etchant prepared in Step 1. Rinse the corroded sample surface with ethanol after 5 to 10 seconds of corrosion, and place it in the oven after drying. The grain boundaries were observed under a metallographic ...

technical field

[0001] The invention belongs to the technical field of metallographic detection, in particular to a metallographic corrosion method for rapidly displaying special steel grain boundaries. Background technique

[0002] Metallographic detection is an important means for metal material research or production enterprises to grasp the product structure and grain size in time during the production process. Through the metallographic detection results, the quality problems in the production process can be analyzed, and the process parameters can be changed and optimized. Control and improve product quality. Metallographic corrosion is an important part of metallographic detection. Only by using a suitable etchant to corrode a clear metallographic structure and grain boundary can the observation of the metallographic structure and the analysis of the grain size and the content of each phase be carried out, so as to accurately determine the heat treatment. Whether the...

Examples

Embodiment 1

[0023] A metallographic corrosion method for rapidly displaying special steel grain boundaries, comprising the following steps:

[0024] Step 1, prepare dinitrophenol corrosion agent;

[0025] Step 2. Roughly grind the surface of the special steel sample to remove the rust layer on the surface. The coarsely ground sample is finely ground on sandpaper; the finely ground sample surface is polished to obtain a bright and scratch-free surface. sample surface;

[0026] Step 3. At room temperature, completely immerse the polished surface of the special steel sample obtained in Step 2 in the dinitrophenol etchant prepared in Step 1. Rinse the corroded sample surface with ethanol after 5 to 10 seconds of corrosion, and place it in the oven after drying. The grain boundaries were observed under a metallographic microscope.

Embodiment 2

[0028] A metallographic corrosion method for rapidly displaying special steel grain boundaries, comprising the following steps:

[0029] Step 1. Prepare dinitrophenol etchant; at room temperature, thoroughly mix analytically pure grade phenol with a mass volume ratio of 5g:5mL and nitric acid with a mass concentration of 65%, and then obtain dinitrophenol etchant in 3-5 minutes.

[0030] Step 2. Roughly grind the surface of the special steel sample to remove the rust layer on the surface. The coarsely ground sample is finely ground on sandpaper; the finely ground sample surface is polished to obtain a bright and scratch-free surface. sample surface;

[0031] Step 3. At room temperature, completely immerse the polished surface of the special steel sample obtained in Step 2 in the dinitrophenol etchant prepared in Step 1. Rinse the corroded sample surface with ethanol after 5 to 10 seconds of corrosion, and place it in the oven after drying. The grain boundaries were observed u...

Embodiment 3

[0034] A metallographic corrosion method for rapidly displaying special steel grain boundaries, comprising the following steps:

[0035] Step 1: Prepare dinitrophenol etchant; at room temperature, thoroughly mix analytically pure grade phenol with a mass volume ratio of 5g:5mL and nitric acid with a mass concentration of 65% to obtain dinitrophenol etchant.

[0036] Step 2. Roughly grind the surface of the special steel sample to remove the rust layer on the surface. The coarsely ground sample is finely ground on sandpaper; the finely ground sample surface is polished to obtain a bright and scratch-free surface. sample surface;

[0037] Step 3. At room temperature, completely immerse the polished surface of the special steel sample obtained in Step 2 in the dinitrophenol etchant prepared in Step 1. Rinse the corroded sample surface with ethanol after 5 to 10 seconds of corrosion, and place it in the oven after drying. The grain boundaries were observed under a metallographic ...

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