Oxide dispersion-strengthened iron-based alloy powder and characterization method thereof

Patent metadata

Field	Value
Publication number	US-2023151462-A1
Application number	US-202318155739-A
Country	US
Kind code	A1
Filing date	Jan 18, 2023
Priority date	Jul 27, 2018
Publication date	May 18, 2023
Grant date	—

Abstract

A characterization method of an oxide dispersion-strengthened (ODS) iron-based alloy powder is provided. The characterization method comprises separating the strengthening phases from the powder matrix through electrolysis, and analyzing and characterizing the strengthening phases using an electron microscope.

First claim

What is claimed is:

1 . A characterization method of an oxide dispersion-strengthened (ODS) iron-based alloy powder, comprising the following steps:
Step A: putting the ODS iron-based alloy powder and foam nickel into a beaker filled with absolute ethanol together, and then dispersing by ultrasonic to obtain foam nickel filled with the ferromagnetic ODS iron-based alloy powder; Step B: putting the foam nickel filled with the ODS iron-based alloy powder into an electrolyte, electrolyzing, to separate the strengthening phases from the iron-based alloy matrix, and then conducting magnetic separation to obtain an electrolyte containing the strengthening phase particles; Step C: extracting the electrolyte containing the strengthening phase particles prepared by electrolyzing, and diluting with absolute ethanol to obtain a diluted suspension; Step D: dispersing the diluted suspension by ultrasonic to obtain a solution containing nano-scaled to submicron-scaled strengthening phase particles for use; Step E: dripping the solution containing the nano-scaled to submicron-scaled strengthening phase particles for use onto an ultrathin carbon support film for several times, and then drying to obtain a TEM test sample; and Step F: characterizing the strengthening phase particles of the TEM test sample via an electron microscope, wherein the ODS iron-based alloy powder comprises a matrix and strengthening phases; the strengthening phases comprise at least two types of strengthening phase particles with different sizes; the two types of the strengthening phase particles with different sizes are particle A and particle B, a size of the particle A is less than or equal to 50 nm, and a size of the particle B is larger than 50 nm and less than or equal to 200 nm, a volume of the particle A accounts for 85-95% of a total volume of all the strengthening phase particles, and a content of the strengthening phases is 0.5-3.0 wt. %, wherein the matrix is a Fe—Cr—W—Ti alloy, wherein the strengthening phases comprise crystalline Y 2 O 3 , amorphous Y 2 O 3 , Y—Ti—O, Y—Cr—O and Y—W—O.

2 . The characterization method of the ODS iron-based alloy powder according to claim 1 , wherein the volume of the particle A accounts for 88-93% of the total volume of all strengthening phase particles.

3 . The characterization method of the ODS iron-based alloy powder according to claim 1 , wherein,
in step A, a particle size of the ODS iron-based alloy powder is less than 150 μm, a purity of the foam nickel used in step A is higher than or equal to 99.98%, and an ultrasonic dispersion time is 3-5 min.

4 . The characterization method of the ODS iron-based alloy powder according to claim 1 , wherein a composition of the electrolyte used in step B according to percentage by mass comprises: 2%-15% of a substance A, 15%-25% of acetylacetone, 3%-15% of glycerol, and the rest being absolute ethanol, a pH value of the electrolyte is 7-9, the substance A is selected from at least one of tetramethylammonium chloride, tetramethylammonium bromide, hexadecyl trimethyl ammonium chloride, and hexadecyl trimethyl ammonium bromide,
the electrolysis process in step B comprises: using the foam nickel filled with the ODS iron-based alloy powder as an anode, and a conductive material containing iron as a cathode, wherein the conductive material containing iron is selected from one of stainless steel, low-carbon steel, and pure iron, the electrolysis is carried out by applying a constant-voltage of 3-6 V at room temperature for 10-20 min.

5 . The characterization method of the ODS iron-based alloy powder according to claim 1 , wherein,
in step B, a magnetic separation is conducted on the electrolyte containing the strengthening phase particles using a magnetic field so as to remove ferromagnetic powder particles, in step C, the electrolyte containing the strengthening phase particles is diluted with absolute ethanol by a factor of 5-10.

Assignees

• Univ Central South

Inventors

• Liu Zuming
• Li Quan
• Huang Boyun
• Lv Xueqian
• Peng Kai
• Zhao Fan

Classifications

• C22C33/0292 Primary

  with more than 5% preformed carbides, nitrides or borides · CPC title

• C22C38/22 Primary

  with molybdenum or tungsten · CPC title

• B22F9/04 Primary

  starting from solid material, e.g. by crushing, grinding or milling ({C22C1/1084 takes precedence}; crushing, grinding or milling, in general, see the relevant subclasses, e.g. B02C) · CPC title

• B22F2302/25

  Oxide · CPC title

• G01N23/04

  and forming images of the material · CPC title