Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

Display method for precipitation condition of ferrite along original austenite

A display method and a technology for displaying conditions, applied in the field of iron and steel structure analysis, can solve the problems of inability to study and analyze ferrite precipitation, observe the original austenite structure, etc.

Pending Publication Date: 2021-01-08
BAOSTEEL SPECIAL STEEL SHAOGUAN CO LTD
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] However, when the austenite is completely transformed into ferrite and pearlite structure, since there is no austenite structure, after corroding the sample at this time, it is impossible to observe the ferrite structure and pearlite structure at the same time. To the original austenite structure, so the relationship between the precipitation of ferrite and the original austenite cannot be studied and analyzed

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Display method for precipitation condition of ferrite along original austenite
  • Display method for precipitation condition of ferrite along original austenite
  • Display method for precipitation condition of ferrite along original austenite

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0059] A method for displaying ferrite precipitation along prior austenite, comprising:

[0060] S1. Sample preparation: Prepare a sample made of 20CrMnTi steel, and polish the detection surface of the sample.

[0061] S2. Microstructure treatment: put the sample into the heat treatment furnace with the polished detection surface facing up, heat it to 890°C, and keep it for 60 minutes to completely austenitize the sample and form an iron oxide layer on the detection surface; then The samples were taken out of the heat treatment furnace for air cooling, so that the austenite under the iron oxide layer was transformed into ferrite and pearlite.

[0062] S3. Grinding and polishing of the detection surface: knock out the iron oxide scale on the detection surface of the sample; then finely grind the sample so that the area of ​​the iron oxide layer retained on the detection surface accounts for 5%; and then polish the detection surface to make it form a mirror.

[0063] S4. Corro...

Embodiment 2

[0065] A method for displaying ferrite precipitation along prior austenite, comprising:

[0066] S1. Sample preparation: Prepare a sample made of 35 steel, and polish the detection surface of the sample.

[0067] S2. Microstructure treatment: put the sample into the heat treatment furnace with the polished detection surface facing up, heat it to 860°C, and keep it for 30 minutes to completely austenitize the sample and form an iron oxide layer on the detection surface; then The samples were taken out of the heat treatment furnace for air cooling, so that the austenite under the iron oxide layer was transformed into ferrite and pearlite.

[0068] S3. Grinding and polishing of the detection surface: knock out the iron oxide scale on the detection surface of the sample; then finely grind the sample so that the area of ​​the iron oxide layer retained on the detection surface accounts for 50%; and then polish the detection surface to make it form a mirror.

[0069] S4. Corrosion ...

Embodiment 3

[0071] A method for displaying ferrite precipitation along prior austenite, comprising:

[0072] S1. Sample preparation: Prepare a sample made of 20Cr steel, and polish the detection surface of the sample.

[0073] S2. Microstructure treatment: put the sample into the heat treatment furnace with the polished detection surface facing up, heat it to 890°C, and keep it for 30 minutes to completely austenitize the sample and form an iron oxide layer on the detection surface; then The samples were taken out of the heat treatment furnace for air cooling, so that the austenite under the iron oxide layer was transformed into ferrite and pearlite.

[0074] S3. Grinding and polishing of the detection surface: knock out the iron oxide scale on the detection surface of the sample; then finely grind the sample so that the area of ​​the iron oxide layer retained on the detection surface accounts for 95%; and then polish the detection surface to make it form a mirror.

[0075] S4. Corrosio...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a display method for the precipitation condition of ferrite along original austenite, and belongs to the field of steel structure analysis. The display method comprises the steps that a sample with a ground detection surface is subjected to heat treatment, so that the sample is completely austenitized, and an iron oxide layer located on the detection surface is formed; thenthe sample is cooled, so that austenite under the iron oxide layer is converted into ferrite and pearlite; the detection surface with the iron oxide layer is ground and polished, and the iron oxide layer on part of the area of the detection surface is reserved; first-stage corrosion treatment is carried out on the detection surface by adopting a first corrosive liquid, so that an austenite grain boundary is displayed; and second-stage corrosion treatment is carried out on the detection surface by adopting a second corrosive liquid, so that a ferrite grain boundary and a pearlite grain boundaryare displayed, wherein the first corrosive liquid is a mixed solution of nitric acid, dish-washing liquid and ethanol, and the second corrosive liquid is a nitric acid alcohol solution. The distribution condition of the original austenite structure can be displayed while the ferrite structure and the pearlite structure are displayed.

Description

technical field [0001] The present application relates to the field of steel structure analysis, and in particular, to a method for displaying the precipitation of ferrite along prior austenite. Background technique [0002] In the case of normalizing and annealing, hypoeutectoid steel generally obtains ferrite and pearlite structures. According to the iron-carbon phase diagram, when the austenite is cooled to A 3 At the line temperature, ferrite begins to precipitate, that is, pro-eutectoid ferrite. As the temperature decreases, the precipitation process of proeutectoid ferrite continues, and when the temperature continues to drop to A r1 At temperature, austenite with eutectoid composition transforms into pearlite structure, and finally a structure composed of ferrite and pearlite is obtained. [0003] However, when the austenite is completely transformed into ferrite and pearlite, since there is no austenite, it is impossible to observe the ferrite and pearlite at the ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): G01N1/32G01N1/44
CPCG01N1/32G01N1/44
Inventor 董凤奎杨雄强廖卓文刘年富钟凡何健楠罗新中刘海鹏刘金源龙鹄
Owner BAOSTEEL SPECIAL STEEL SHAOGUAN CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com