SU1727153A2 - Method of polycrystalline structure modeling - Google Patents

Abstract

The invention relates to solid state physics and can be used to study the structure of polycrystals. The purpose of the invention is to extend the functionality by determining the degree of coincidence of the grids and the angles of disorientation. Pass a beam of light through disk storage media with holes simulating the crystal structure of the material, with a uniform rotation of one disk relative to another and record the transmitted light intensity. New is the focusing of the contact surface of the disks on the surface of the recorder and the determination of the misorientation angle according to the intensity of the transmitted light beam on the angle of rotation of the moving disk. 1 hp ff. 2 Il.

Description

This invention relates to solid state physics and can be used to study the structure of polycrystals.

The closest to the proposed technical essence and the achieved result is a method of modeling the structure of grain boundaries, which means that the information carriers are made in the form of disks, and the image of the lattice scheme of atoms of matter on them is in the form of a system of holes corresponding to a certain crystallographic plane , the disks are aligned to the full coincidence of all the holes, mechanically continuously rotate one disk relative to another around the axis perpendicular to the disk plane, simultaneously with the rotation m is passed through the discs parallel beam of light directed perpendicularly to the plane of the discs, and fixed intensity distribution of the transmitted light beam.

The disadvantage of this method is the impossibility of determining the degree of coincidence of the grain lattices in the boundary, identifying the most real structures of the grain boundaries and accurately determining the corresponding disorientation angles, as well as providing a clear picture of all possible structures of the boundaries.

The purpose of the invention is to expand the functionality by determining the degree of coincidence of the gratings of grains in the boundary and the corresponding angles of disorientation.

FIG. Figure 1 shows schematically an apparatus for carrying out the proposed method; in fig. 2 is a diagram illustrating the proposed method.

In the groove of the yoke 1, the fixed 2 and the movable 3 are coaxially arranged.

hO

J

k

ate with

ho

skies with through holes, one of which is located in the center of the disks, arranged according to a scheme that coincides with the arrangement of atoms in a certain crystal plane and having equal diameters. The movable disk 3 is connected by a gear 4 mounted on it with the engine 5, which provides a constant speed of rotation of the movable disk. 3.

Above the clip 1 with the disks 2 and 3 is located the source 6 of a parallel beam of light. The yoke 1 and the light source 6 are arranged in such a way that the parallel beam t of light is always directed perpendicular to the plane of the disks.

A focusing element 7 is placed between the holder 1 and the recording unit 8, which allows a clear picture of the intensity distribution of the transmitted light beam to be recorded on the screen of the recording device without being distorted by focusing the disk contact surface on the screen.

Under the clip 1 with the disks 2 and 3 is placed block 8, recording the distribution of the intensity of the light beam transmitted through the disks and its integral intensity using a flat photocell.

The magnitude of the integrated intensity using a recording unit consisting of a DC amplifier 9 and a tape recorder 10 is recorded on a chart tape.

The device works as follows.

In the cage 1 with the recess, the disk 2 is fixedly fixed with through holes, one of which is located in the center, of the disk. On top of the fixed disk 2 fixed in the cage, another movable disk 3, pre-fixed on the gear 4, is mounted.

The disks 2 and 3 are installed in such a way that there is a complete coincidence of all the holes, as evidenced by the maximum value of the integral intensity.

A parallel beam of light perpendicular to the plane of the disks 2 and 3 is directed from the source 6 and the picture of the intensity distribution of the transmitted light beam is fixed, providing the most accurate image by moving the focusing device 7 relative to the holder.

The movable disk 3 is brought into engagement with the engine 5, and at the same time includes a tape recorder device.

and a motor 5 rotating the movable disk 3.

Fix the value of the integrated intensity of the transmitted beam of light I on the chart tape, depending on time t

A picture of the intensity distribution of the transmitted light beam, corresponding to the maxima on the I l (t) curve, is photographed, and the angle of disorientation is determined

The angle of disorientation of grains in the border

p (hail.), corresponding to the maxima on

dependences I t (t). determined by the formula

 360 °

where 1 is the distance on the chart tape from the maximum corresponding to the complete coincidence of the holes (the largest value) to the maximum corresponding to a specific structure, mm;

n is the rotational speed of the moving disk, rpm;

V is the speed of movement of the chart tape, mm / min.

When measuring I with an accuracy of ± 1 mm, moving the chart tape at a speed of V 900 mm / min, and rotating the moving disk at a speed of 1/300 rpm, the angle (p can be determined with an accuracy of ± 0.5 s.

FIG. 2 shows the dependence I l (t) obtained by rotating the movable disk at a speed of 1/300 rpm; the speed of movement of the chart tape is 4 mm / min. The arrangement of the holes on the disk corresponds to the arrangement of atoms in the plane. :

A DSM 2U motor was used to rotate the movable disk, and a potentiometer was used to record the I l (t) curve.

The Industar 55y photo lens was used as the focusing device, and the FESS-UU photocell was used to measure the integrated intensity.

Compared with the known method, the proposed method allows, by measuring the integrated intensity of the transmitted light beam I, depending on the angle of rotation of the disks p, to determine the degree of coincidence of the gratings in the boundary depending on the angle of disorientation, to reveal the most real structures of the boundaries as corresponding to the maxima on the curve I l (t), while obtaining a clear image of this structure.

Claims (2)

Claim 1. Method for modeling the structure of polycrystals auth.St. No. 1651313, which is based on the fact that, in order to extend the functionality by determining the degree of coincidence of the gratings of grains in the boundary and the corresponding angles of disorientation, the values of the angles are determined disorientation according to the integral intensity of the transmitted beam of light on the angle of rotation of the moving disk. 2. A method according to claim 1, characterized in that, in order to improve the accuracy of determining the angles of disorientation, the plane of contact of the disks is pre-focused on the surface of the recorder. at h - LJ-J-LKJ