GOST 21073.4-75
GOST 21073.4−75 ferrous Metals. Determination of grain size planimetric method (Change No. 1)
GOST 21073.4−75
Group B09
INTERSTATE STANDARD
METALS NONFERROUS
Determination of grain size planimetric method
Non-ferrous metals. Determination of grain size bu planimetric method
AXTU 1709
Date of introduction 1976−07−01
Resolution The state Committee of standards of Ministerial Council of the USSR from 15 August 1975 N 2164 the introduction of set with 01.07.76
Restriction expiration removed by Protocol No. 2−92 of the Interstate Council for standardization, Metrology and certification (ICS 2−93)
EDITION with Change No. 1, approved in December 1983 (ICS 3−84).
This standard applies to non-ferrous metals and sets the planimetric method for the determination of grain size.
Method it is used in cases that require high measurement accuracy for example, to control scales of the microstructures of the special appointments, etc.
1. GENERAL REQUIREMENTS
1.1. General requirements for test method — according to GOST 21073.0−75.
2. TESTING
2.1. For the determination of grain size planimetric method for browsing the surface of the cone and choose at least three typical places, and when determining statistical characteristics 
(Changed edition, Rev. N 1).
2.2. When determining the grain size using the increase to the field of view was 80−200 beans.
2.3. To determine the amount of grain the image of each of the measured locations see on the frosted glass of the microscope or on photomicrographs.
3. PROCESSING OF THE RESULTS
3.1. The determination of the amount of grain produced by planimetrically square made up of whole grains, and count the number of these grains
.
Methods planimetrically given in the Appendix.
The number of grains included in the planimetric area should be at least 50% of grains within a field of view.
3.2. The result of the test accept the following values:
a) the average cross-sectional area of the grain , mm
;
b) the average number of grains per 1 mm
square sections;
C) minimum and maximum cross-sectional area of the grain and
, mm
;
d) the standard deviation of the individual measurements of the cross-sectional area of the grain , m
m.
3.3. The calculation is made according to the formulas:
3.4. As reference values characterizing the grain size at determine its planimetric method can be determined the average grain diameter:
3.1−3.4. (Changed edition, Rev. N 1).
APPLICATION (recommended). METHODS PLANIMETRICALLY
APP
Recommended
To measure the area are encouraged to use mathematical instruments such as a note type of Amsler.
It is possible to use manual methods of planimetrically listed below.
1. The straight-line method
1.1. On planimetered area is applied to parallel lines. Distance between adjacent parallel lines must be the same.
Precision planimetrically is greater, the smaller the distance between adjacent parallel lines. The recommended distance between adjacent parallel lines is 1 mm.
Note. To apply parallel lines on the square you planimetrical a pencil or other tool on a micrograph or on the matte glass of the microscope or projector, as well as the imposition in advance made pattern on a thin transparent film.
1.2. Measure the total length of all deposited parallel lines trapped inside the planned area, a ruler or odometer.
1.3. Size planimetering area in millimetres calculated by the formula
where — the total length of all parallel lines, mm.
— the distance between adjacent parallel lines, mm.
— increase (linear).
2. The grid method
2.1. On planimetered area applied a small uniform grid. Precision planimetrically the more, the finer the mesh. Recommended mesh square mesh size of 1x1 mm.
Note. Apply the mesh recommended by superimposing on the micrograph or the frosted glass of the microscope or projector pre-made template on a thin transparent film (samples).
2.2. Count the number of grid cells trapped inside planimetrically square. Cell that crossed the border planimetrically square, I think for the whole in that case, if half or more than half of their area is inside planimetrically square; if less than half of the area the cell is inside planimetering area, then this cell is not think.
2.3. Size planimetrically square in mm
is calculated by the formula
where is the number of grid cells inside planimetrically square pieces;
— the area of one cell of the grid, mm
;
— increase (linear).
3. Weight method
3.1. Planimetrically square cut out from the micrograph, printed on the film, weight of 1 mwhich is precisely defined.
The accuracy of planimetrically the more, the more accurately cut planimetria area.
3.2. Weigh cut planimetered area on an analytical balance.
Note. Determination of mass 1 mand weighing the cut area must be produced on film the same batch and thickness shown, otfiksirovat, washed and dried in the same conditions.
3.3. Size planimetrically square in mm
is calculated by the formula
where is the mass planimetrically cut square, g;
— weight of 1 m
of film, g;
— increase (linear).
