CN-122016787-A - Method for rapidly determining interface and load angle of TiAl alloy sheet

Abstract

The invention discloses a method for rapidly determining TiAl alloy sheet interface and load angle, which relates to the technical field of material performance test and has the technical scheme that a TiAl alloy sample containing a sheet group to be observed is prepared, and the sample comprises two adjacent mutually perpendicular observation planes; the method comprises the steps of carrying out grinding and polishing treatment on two observation planes, establishing a space rectangular coordinate system by taking an intersection line of the two observation planes as a Y axis, carrying out metallographic corrosion on a ground sample, respectively measuring an included angle between a slice interface and an X axis in a first observation plane and an included angle between the slice interface and a Z axis in a second observation plane, calculating a normal vector of the slice interface based on the two included angles, and calculating an included angle between the slice interface and a load direction based on the normal vector. The invention obtains the direction vectors of the slice interfaces on different observation planes through the optical microscope, calculates the included angle between the load direction and the slice interfaces, and has the advantages of simple operation, large observable area, high included angle determination speed and the like.

Inventors

• CHE HANQING
• WANG YAN
• LI HE
• LI SHAOLONG
• HUANG XIAOXU

Assignees

• 重庆大学

Dates

Publication Date

20260512

Application Date

20260128

Claims (10)

1. 1. A method for rapidly determining the interface and load angle of a TiAl alloy sheet, which is characterized by comprising the following steps: S1, preparing a TiAl alloy sample containing lamellar clusters to be observed, wherein the sample at least comprises two adjacent mutually perpendicular observation planes; S2, performing grinding and polishing treatment on the two observation planes according to a standard metallographic sample preparation method; s3, establishing a space rectangular coordinate system by taking the intersection line of the two observation planes as a Y axis, wherein the Z axis is a preset load direction; s4, carrying out metallographic corrosion on the polished sample to expose a sheet interface of the sheet group to be observed; s5, respectively measuring the included angle between the lamellar interface and the X axis in a first observation plane under an optical microscope And an angle with the Z axis in a second observation plane ; S6, based on the included angle And said included angle Calculating the normal vector of the lamellar interface; S7, calculating an included angle between the lamellar interface and the load direction based on the normal vector 。
2. 2. The method according to claim 1, wherein in step S1, the sample is a cubic sample, and the two observation planes are two adjacent surfaces on the cubic sample.
3. 3. The method according to claim 1, wherein in step S3, the space rectangular coordinate system is a right-hand coordinate system.
4. 4. A method for rapidly determining the interface and load angle of a TiAl alloy sheet according to claim 1, wherein in step S6, the calculating the normal vector of the sheet interface comprises: S61, according to the included angle Determining a first linear vector of intersection of the lamellar interface with the first observation plane; S62, according to the included angle Determining a second linear vector of the lamellar interface intersecting the second observation plane; And S63, obtaining the normal vector of the slice interface by calculating the cross product of the first linear vector and the second linear vector.
5. 5. The method for rapidly determining a TiAl alloy sheet interface and a load angle according to claim 4, wherein in step S7, the angle between the sheet interface and the load direction is calculated The method comprises the following steps: calculating the included angle between the load direction and the normal vector of the lamellar interface ; Based on the included angle Calculating the included angle between the lamellar interface and the load direction according to the geometric relationship 。
6. 6. The method for rapidly determining the interface and the load angle of the TiAl alloy sheet according to any one of claims 1 to 5, wherein in the step S4, the etching solution used for metallographic etching is a mixed solution of hydrofluoric acid, nitric acid and water.
7. 7. The method for rapidly determining the interface and load angle of the TiAl alloy sheet according to claim 6, wherein the volume ratio of hydrofluoric acid, nitric acid and water in the corrosive liquid is HF:HNO 3 ：H 2 O=3:5:92.
8. 8. A method for rapidly determining interface and load angle of a TiAl alloy sheet according to any one of claims 1 to 5, wherein the metallographic corrosion time is 20 seconds.
9. 9. A method for rapidly determining interface and load angle of a piece of TiAl alloy according to any of claims 1-5, wherein the TiAl alloy is Ti45Al8Nb alloy.
10. 10. A method for rapidly determining interface and load angle of a piece of TiAl alloy according to claim 9, wherein the Ti45Al8Nb alloy is heat treated at 1300 ℃ for 1 hour.

Description

Method for rapidly determining interface and load angle of TiAl alloy sheet Technical Field The invention relates to the technical field of material performance testing, in particular to a method for rapidly determining TiAl alloy sheet interface and load angle. Background The TiAl alloy has low density, high specific yield strength, high specific stiffness, good oxidation resistance and high-temperature creep resistance. The specific yield strength of the TiAl alloy is superior to that of the high-temperature alloy and the traditional Ti alloy in 600-800 ℃, and the specific modulus is far higher than that of the Ti alloy and the high-temperature alloy, so that the TiAl alloy has great high-temperature application potential. Therefore, researchers have conducted extensive experimental studies on the mechanical properties of TiAl alloys. In the research of the mechanical properties of TiAl alloy, microhardness test and microcolumn compression experiment are common micro-nano scale mechanical characterization means. However, the mechanical response of the full-lamellar TiAl alloy is closely related to the angle of the load direction relative to the lamellar interfaces within the lamellar clusters. Therefore, it is important to accurately acquire the angle information before performing the relevant test. Currently, the angle relationship is determined by an Electron Back Scattering Diffraction (EBSD) technique, that is, the crystal orientation of the α 2 sheet is first identified and then the angle between the α 2 sheet and the load direction is calculated (for example, document Lamellar transformation in near-γ TiAl alloys-Quantitative analysis of kinetics and microstructure）., however, since the TiAl alloy sheet width is mostly submicron or even nanometer, the EBSD analysis needs to use a very small scanning step and can only be performed in a small area, which not only results in low detection efficiency and long time consumption, but also causes a significant limitation on the observation area. Therefore, the research and design of a method for overcoming the defects of TiAl alloy sheet interfaces and load angles is an urgent problem to be solved at present. Disclosure of Invention In order to solve the defects in the prior art, the invention aims to provide a method for rapidly determining the interface and the load angle of a TiAl alloy sheet layer, the invention utilizes an optical microscope to obtain the direction vectors of the sheet layer interface on different observation planes, and an included angle between the load direction and the slice interface is calculated based on the direction vector, so that the quick representation of the included angle between the load direction and the slice interface is realized. Compared with the Electron Back Scattering Diffraction (EBSD) technology, the method effectively solves the problems of limited observation area, low test efficiency and the like in the TiAl alloy orientation characterization, and has the remarkable advantages of simple operation, large observable area, high determination speed of included angles and the like. The technical aim of the invention is realized by the following technical scheme that the method for rapidly determining the interface and the load angle of the TiAl alloy sheet comprises the following steps: S1, preparing a TiAl alloy sample containing lamellar clusters to be observed, wherein the sample at least comprises two adjacent mutually perpendicular observation planes; S2, performing grinding and polishing treatment on the two observation planes according to a standard metallographic sample preparation method; s3, establishing a space rectangular coordinate system by taking the intersection line of the two observation planes as a Y axis, wherein the Z axis is a preset load direction; s4, carrying out metallographic corrosion on the polished sample to expose a sheet interface of the sheet group to be observed; s5, respectively measuring the included angle between the lamellar interface and the X axis in a first observation plane under an optical microscope And an angle with the Z axis in a second observation plane; S6, based on the included angleAnd said included angleCalculating the normal vector of the lamellar interface; S7, calculating an included angle between the lamellar interface and the load direction based on the normal vector 。 Preferably, in step S1, the sample is a cubic sample, and the two observation planes are two adjacent surfaces on the cubic sample. Preferably, in step S3, the space rectangular coordinate system is a right-hand coordinate system. Preferably, in step S6, the calculating the normal vector of the lamellar interface specifically includes: S61, according to the included angle Determining a first linear vector of intersection of the lamellar interface with the first observation plane; S62, according to the included angle Determining a second linear vector of the lamellar interface intersecting th