GOST 25.503-97

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  ГОСТ 25.503-97

GOST 25.503−97 Calculations and strength tests. Methods of mechanical testing of metals. Method of compression testing

GOST 25.503−97

Group B09

INTERSTATE STANDARD

Calculations and strength tests. Methods of mechanical testing of metals

METHOD OF COMPRESSION TESTING

Design calculation and strength testing. Methods of mechanical testing of metals. Method of compression testing

ISS 77.040.10
AXTU 0025

Date of introduction 1999−07−01

Preface

1 DEVELOPED by Voronezh state forestry Academy (VGLTA), all-Russian Institute of light alloys (VILS), Central research Institute of building structures (tsniisk im. Kucherenko), all-Russian research Institute of standardization and certification in engineering (VNIINMASH) of Gosstandart of the Russian Federation

INTRODUCED by Gosstandart of Russia

2 ADOPTED by the Interstate Council for standardization, Metrology and certification (minutes No. 12 dated November 21, 1997)

The adoption voted:

The name of the state	The name of the national authority for standardization
The Republic Of Azerbaijan	Azgosstandart
The Republic Of Armenia	Armastajad
The Republic Of Belarus	Gosstandart Of Belarus
The Republic Of Kazakhstan	Gosstandart Of The Republic Of Kazakhstan
Kyrgyz Republic	Kyrgyzstandart
The Republic Of Moldova	Moldovastandart
Russian Federation	Gosstandart Of Russia
The Republic Of Tajikistan	Tajikistandart
Turkmenistan	The main state inspection of Turkmenistan
The Republic Of Uzbekistan	Standards
Ukraine	Gosstandart Of Ukraine

3 Decree of the Russian Federation Committee on standardization, Metrology and certification dated June 30, 1998 N 267 interstate standard GOST 25.503−97 introduced directly as state standard of the Russian Federation from July 1, 1999

4 REPLACE GOST 25.503−80

5 REISSUE

1 Scope

This standard establishes methods of static compression tests at a temperature of 20°C to characterize the mechanical properties of ferrous and nonferrous metals and alloys.

The standard defines the method for testing samples in compression to construct the curve of hardening, determine the mathematical relationship between the flow stress and the strain degree and estimate the parameters of power law equation ( — voltage current if =1, the index of strain hardening).

The mechanical properties of hardening curve and its parameters defined in this standard, can be used in the following cases:

— choice of metals, alloys and justification of design solutions;

— statistical acceptance control regulation of mechanical characteristics and quality assessment of metal;

— development of technological processes and product design;

— strength calculation of machine parts.

The requirements set out in sections 4, 5 and 6 are mandatory, other requirements are recommended.

2 Normative szybki

The present standard features references to the following standards:

GOST 1497−84 (ISO 6892−84) Metals. Test methods tensile

GOST 16504−81 System of state testing products. Testing and quality control. Key terms and definitions

GOST 18957−73* strain gauges for measuring linear deformations of building materials and structures. General specifications
________________
* On the territory of the Russian Federation is cancelled.

GOST 28840−90 Machine for testing materials in tension, compression and bending. General technical requirements

3 Definitions

3.1 In this standard apply, the following terms with respective definitions:

3.1.1 diagram of test (compression): Graph of load of absolute deformation (shortening) of the sample;

3.1.2 hardening curve: a Graph of the voltage current from the logarithmic strain;

3.1.3 axial compressive load: the Load acting on the specimen at the moment of the test;

3.1.4 conditional nominal voltage : Voltage, determines the ratio of load to initial cross sectional area;

3.1.5 the flow stress : Stress, exceeding the yield strength, determined by the ratio of the load to effect for the time of testing, the cross sectional area of the specimen at a uniform deformation;

3.1.6 the limit of proportionality in compression : stress at which a deviation from a linear relationship between load and absolute shortening of the sample reaches a value at which the tangent of the angle formed by the tangent to the graph at the point with axle loads increased by 50% of its value at the linear elastic portion;

3.1.7 the limit of elasticity under compression : the Stress at which a relative residual deformation (shortening) of the sample () reaches 0.05% of the original calculated height of the sample;

3.1.8 yield point (physical) compression : the Lowest voltage at which the sample is deformed without any appreciable increase in the compressive load;

3.1.9 yield strength in compression : stress at which a relative residual deformation (shortening) of the sample reaches 0.2% of the initial calculated specimen height;

3.1.10 limit of compressive strength : the Stress corresponding to the highest load just before the fracture;

3.1.11 the rate of strain hardening : Power indicator approximating curves hardening equation , characterizes the ability of a metal to hardening during uniform plastic deformation.

4 Shape and dimensions of samples

4.1 Tests carried out on samples of four types: cylindrical and prismatic (square or rectangular), smooth the ends of I-III types (figure 1) and the end undercut type IV (figure 2).

Figure 1 — Experimental models I-III types

Figure 1 — Experimental models I-III types

Figure 2 — Experimental models of type IV

Figure 2 — Experimental models of type IV

4.2 Type and size of the sample chosen in table 1.


Table 1

Sample type	The initial diameter of the cylindrical- rihackova sample , mm	The initial thickness of prismati- IC sample , mm	Working (initial calculated) sample height *, mm	Define feature	Note
I	20	20	100	The modulus of elasticity, limit of proportionality	Figure 1
II	6−30	5−30		The limit of proportionality, elastic limit
III	6; 10; 15; 20; 25; 30	5; 10; 15; 20; 25; 30	Determined by the application And	Physical yield point, yield strength. The curve of hardening up to values of the logarithmic strain **
IV	6 10 15 20 25 30	-	The curve of hardening	Figure 2. The thickness and height of the collar is determined by the application And
* The height of the prismatic sample set on the basis of its area , equating it to the nearest square through . ** To build the curves apply only hardening cylindrical samples. Note — the width of the prismatic specimens is determined from the ratio .

4.3 the place of cutting of blanks for samples and the direction of the longitudinal axis of the sample relative to the workpiece should be given in the normative document on the rules of sampling, blanks and samples for the products.

4.4 Samples are processed on machine tools. Depth of cut in the last passage should not exceed 0.3 mm.

4.5 Heat treatment of metals should be carried out before the finishing operations of machining of the samples.

4.6 measurement error of the diameter and cross-sectional dimensions of the prismatic specimen before test should not be more than, mm:

0,01 — for sizes up to 10 mm;

0,05 — for dimensions above 10 mm.

The measurement of the diameter of the samples before the test is carried out in two mutually perpendicular sections. The measurement results are averaged, we calculate the cross-sectional area of the specimen, rounded in accordance with table 2.


Table 2

The cross-sectional area of the specimen, mm	Rounding values
SV. 20 to 100 incl.	0,1
«100» 200 «	0,5
«200	1,0

4.7 measurement Error of height of specimen before test should not be more than, mm:

0,01 — for samples I and II types;

0,01 — for samples of type III, if the type test sample is carried out at a strain of 0.002 and 0.05 mm to >0.002 inch;

0,05 — for samples of type IV.

5 equipment Requirements and equipment

5.1 Tests carried out on compression machinery of all systems and machines stretching (compression zone), meeting the requirements of this standard and GOST 28840.

5.2 When tested in compression testing machine shall be equipped with:

the force transducer and a strain gauge or transducers of force and displacement with a recording device — for determining the mechanical characteristics , , . However, the installation of strain gauge is carried out on the sample in its theoretical part, and recording devices for recording chart ;

— transducers and displacement with a recording device — for determining the mechanical characteristics , , and building hardening curve for specimens type III. The transducer of displacement installed on the active grip of the testing machine. Allowed to measure the absolute deformation (shortening) of the sample, measuring instruments and tools;

the force transducer and measuring instruments and tools — when building a curve of hardening of the samples type IV

.

5.2.1 strain gauges must meet the requirements of GOST 18957.

5.2.2 the total error of the measurement and registration of displacements with a recording instrument of the absolute deformation should not exceed ±2% of measured value.

5.2.3 Recording device must provide a chart record with the following parameters:

the height of the ordinate of the diagram, corresponding to the highest limit value of the measurement range of loads, not less than 250 mm;

— extent of record-axis absolute deformation from 10:1 to 800:1.

5.2.4 the Price of division of scales of measuring instruments and tools when measuring the final specimen height should not exceed, mm:

0,002 — at 0.2 percent	(; for samples I-III types; for samples of type IV, where and  — the initial and final cross sectional area)
0,050 — at 0.2 percent
0,002 — upon 0,002
0,050 — upon 0,002

5.2.5 measurement Error of the final diameter of the specimen and cross-sectional dimensions of the prismatic specimen should not be more than, mm:

0,01 — for sizes up to 10 mm;

0,05 — for dimensions above 10 mm.

6 Preparation and testing

6.1 the Number of samples to estimate the average values of the mechanical characteristics , , , , and must be at least five* if the instrument for the supply of materials not specified a different number.
________________
* If the difference is determined by the characteristics does not exceed 5%, we can restrict the three samples.

6.2 the Number of samples to construct the curve of hardening

6.2.1 To build a curve of hardening of the samples III, IV-type with the subsequent processing of test results by correlation analysis the number of samples is selected depending on the intended curve of hardening and its sites (see Appendix B). For phase I of the curve of hardening (see figure B. 1A) have at least six designs for phase II — not less than five samples for phase III — depending on the value of deformation corresponding to this phase (at least one sample to a range of degrees of deformation =0,10). Hardening curves shown in figures B. 1B and B. 1D and B. 1E B. 1K, the number of samples should be at least 15, and for the curves presented in figure B. 1D, at least eight samples for each of the sections of the curve, separated from each other the highs and lows.

6.2.2 in a limited amount of testing to construct the curve of hardening on samples of type III with a subsequent regression analysis of test results the number of samples should be at least five.

6.3 sample Tests in compression carried out under conditions that provide minimum eccentricity of load application and the safety of the experiments. It is recommended to use the device are given in Appendix B.

6.4 Hardness of the deforming plates must exceed the hardness of the hardened during the test samples of not less than 5 HRC.

The thickness of the deforming plates set depending on the effort created in the sample and taken as equal to 20−50 mm.

6.5 it is Necessary to monitor compliance with the uniformity of deformation in the test specimens in compression (no bochkoobraznye and concavity).

6.5.1 in determining the modulus of elasticity , limit of proportionality and elastic control is carried out with instruments mounted on opposite sides of the prismatic and cylindrical samples, while the normalized difference in the readings of the two instruments should not exceed 10 (15)%.

6.5.2 in determining the yield strength , tensile strength, and when building a curve of hardening of the control is carried out on the equations for cylindrical and prismatic samples:

; ,

where  — the initial estimated height of cylindrical and prismatic specimens used to determine the shortening (base strain gauge), mm;

 — the final design height of cylindrical and prismatic specimens after the test to a specified strain or at fracture, mm.

 — the initial cross-sectional area of the cylindrical specimen, mm;

 — the ultimate cross-sectional area of the cylindrical sample after the test to a specified strain or at fracture, mm;

 — the ultimate cross-sectional area of the prismatic specimen after the test to a specified strain or at fracture, mm(, where is the ending thickness of the prismatic sample,  — the finite width of the prismatic sample, mm);

 — the initial cross-sectional area of the prismatic sample

mm().

6.6 testing of I, II types are the ends of the samples degreased. Lubrication of the ends of the lubricant is unacceptable.

6.7 During the testing of specimens type III allowed the use of lubricant, and testing IV-type lubricant is required.

6.7.1 testing of a type III as the lubricant used engine oil with graphite, lubricant-coolant of the brand-32K and Acrinol 5/5.

6.7.2 testing of type IV as the lubricant used stearin, paraffin, paraffin-stearin mixture or wax. The samples of the lubricating material is applied in a liquid state. The thickness of the lubricant must match the height of the ribs.

6.7.3 permitted use of other lubricants that reduce friction between the samples and the deforming plate.

6.8 testing compression up to the yield limit of the relative speed of deformation choose from 10withto 10with, for a yield point of not more than 10c, and to build the curves of hardening sets of 10withup to 10c. The relative velocity of deformation, it is recommended to take into account the elastic compliance of the system «testing machine — sample» (see GOST 1497). If you selected a speed of relative deformation in the yield could not be achieved directly by the regulation of the testing machine, then it is set from 3 to 30 MPa/s [(0.3 to 3 kgf/mm·s)] regulation of speed of loading before the start of the yield arr

Azza.

6.9 determination of the mechanical properties

6.9.1 Mechanical properties , , , , define:

using strain gauges with manual and automated removal of information (analytical and calculation method of processing);

— recorded test machine autodiaphragm in the coordinates «stress — deformation absolute » given the scale of the recording.

Record charts is done with a step loading with cycles of unloading and continuous application of increasing efforts in these ranges of loading rates and deformation. The scale of the recording:

— axis deformation of at least 100:1;

— axis 1 mm load chart must correspond to not more than 10 MPa (1,0 kgf/mm).

Entry effort and strain should be generally not less than 250h350 mm.

6.9.2 test Results of each sample are recorded in the test Protocol (Appendix G), and the test results of batch samples in a consolidated test report (Annex D).

6.9.3 the Modulus of elasticity in compression is determined on samples of the I type. The procedure of sample testing and a method of constructing a chart of test readings of the force transducer and strain gauge is shown below.

The sample is loaded to a voltage (the voltage corresponds to the expected value of the limit of proportionality).

When the voltage on the sample set strain gauges and load speed-increasing voltage up to (0,70−0,80). The difference between adjacent voltage steps is 0.10.

According to test results build a diagram (figure 3). The modulus of elasticity at compression , MPa (kgf/mm), calculated by the formula

, (1)

where a step load, N (kgf);

the average absolute deformation (shortening) of the specimen during loading at .

Figure 3 — Diagram of test to determine modulus of elasticity in compression

Figure 3 — Diagram of test to determine modulus of elasticity in compression

To determine the modulus of elasticity in compression according to the chart , recorded on the recording instrument (see 4.2), the sample is loaded continuously until . The voltage corresponds to the expected value of the limit of proportionality.

According to the chart, using the formula (1) defined by the modulus of elasticity in compression .

6.9.4 the Limit of proportionality in compression is determined on samples of I and II types. The order of testing of the sample and the method of plotting the readings of the force transducer and strain gauge is shown below.

The sample is loaded to a voltage (the voltage corresponds to the expected value of the limit of proportionality).

When the voltage on the sample set strain gauges and load speed-increasing voltage up to (0,70−0,80), while the difference between adjacent voltage steps is equal to (0,10−0,15). Next, a sample of the load voltage steps equal to 0.02. When the value of the absolute deformation (shortening) of the sample stage voltage is equal to 0.02, will exceed the average value of the absolute deformation (shortening) of the sample (with the same level voltage) in the initial linear elastic portion, 2, to 3 times, the test is stopped.

According to test results build a graph and determine the limit of proportionality in compression (figure 4). For plotting draw , coincident with the initial straight section. Point hold the y-axis , and then directly to an arbitrary level, parallel to the x-axis. On this line lay the cut is equal to half cut . Through the point and the origin is carried out straight , and parallel to it is tangent to the curve. The tangent point determines the load corresponding to the proportionality limit at compression , MPa (kgf/mm), calculated according to the formula

. (2)

Figure 4 — Diagram of test to determine the limit of proportionality in compression

Figure 4 — Diagram of test to determine the limit of proportionality in compression

To determine the limit of proportionality in compression according to the chart , recorded on the recording instrument (see 4.2), the sample is loaded continuously to a voltage in excess of the expected value of the limit of proportionality . According to the chart, using the formula (2) and having the above construction, determine the limit of proportionality in compression .

6.9.5 the elastic Limit in compression is determined on samples of type II. The test procedure according to indications of the force transducer and strain gauge is shown below.

The sample is loaded to a voltage of 0.10(voltage matches the expected value of the elastic limit in compression).

When the voltage on the sample set strain gauges and load speed-increasing voltage up to (0,70−0,80). The difference between adjacent voltage steps is equal to (0,10−0,15). Next, the voltage (0,70−0,80)a sample of the load voltage steps of 0.05. The test is stopped when the residual shortening of the sample exceeds the tolerance value.

According to test results build a graph and determine the limit of elasticity under compression (figure 5).

Figure 5 — Diagram of test to determine the limit of elasticity under compression

Figure 5 — Diagram of test to determine the limit of elasticity under compression

To determine the load calculated absolute deformation (shortening of the specimen) on the basis of the strain gauge base. The value found to increase in proportion to the scale of the graph axis absolute deformation and cut the resulting length of delay on the x-axis to the right of the point . From point draw parallel straight . The point of intersection with the graph determines the height of the ordinates, i.e. the load corresponding to the limit of elasticity at compression , MPa (kgf/mm), calculated according to the formula

. (3)

To determine the limit of elasticity under compression at the diagram , recorded on the recording instrument (see 4.2), the sample is loaded continuously to a voltage in excess of the expected value of the limit of elasticity . According to the chart, using the formula (3) and figure 5, determine the limit of elasticity under compression .

6.9.6 yield strength (physical) in compression is determined on samples of type III.

The sample is continuously loaded to a voltage that exceeds the expected value , and write the chart on recording instrument (see 4.2).

Example determine the load corresponding to the yield strength (physical), shown in figure 6.

Figure 6 — Determination of the load corresponding to the yield strength in compression

Figure 6 — determination of the load corresponding to the yield strength in compression

Yield strength (physical) , MPa (kgf/mm), calculated by the formula

. (4)

6.9.7 yield strength in compression is determined on samples of type III.

The sample is continuously loaded to stresses in excess of the expected value of the conditional yield strength , and write down the chart on recording instrument (see 4.2).

The scale along the axis of deformation of at least 100:1, and the axis of the load — 1 mm diagrams should correspond to not more than 10 MPa (1,0 kgf/mm). Define the diagrams, recorded with the scale on the axis of elongation 50:1 and 10:1, if the initial height of the sample is greater than or equal to 25 and 50 mm, respectively. The resulting chart is rebuilt taking into account the stiffness of the testing machine. The chart (figure 7) define a load corresponding to conventional yield strength (physical) in compression , calculated according to the formula

. (5)

Figure 7 — Diagram of test to determine the conditional yield strength in compression

1 — the characteristic stiffness of the testing machine; 2 — chart recorded on a recording device; a 3 — diagram , are written with allowance for stiffness testing machine

Figure 7 — Diagram of test to determine the conditional yield strength in compression

According to test results build a diagram (figure 8) and determine the load corresponding to conventional yield strength at compression, which is calculated by the formula (5).

Figure 8 — Diagram of test to determine the conditional yield strength in compression

absolute residual deformation (shortening) of the sample

Figure 8 — Diagram of test to determine the conditional yield strength in compression

6.9.8 the Limit of compressive strength is determined on samples of type III.

The sample is continuously loaded until fracture. The greatest load prior to failure of the specimen, taking the load corresponding to the ultimate strength in compression , MPa (kgf/mm), calculated according to the formula

. (6)

6.10 the test procedure for constructing a curve of hardening

6.10.1 To build a curve of hardening of experiencing a series of identical cylindrical samples of types III and IV (see section 3) at several levels of the specified load.

6.10.2 hardening Curve constructed in the coordinates: y — coordinate the flow stress , the abscissa is a logarithmic deformation (figure 9) or in double logarithmic coordinates (figure 10).

Figure 9 — Experimental hardening curve in the coordinates «Sigma"(s)-Epsilon (l)

Figure 9 — Experimental hardening curve in the coordinates

Figure 10 — Experimental hardening curve in logarithmic coordinates

Figure 10 — Experimental hardening curve in logarithmic coordinates

The flow stress , MPa (kgs/mm), calculated by the formula

, (7)

where  — axial compression load (kgf).

The flow stress , MPa (kgs/mm), is determined graphically from the experimental hardening curve in the logarithmic strain (shortening) of the sample , equal to 1.

Logarithmic deformation (shortening) is calculated by the formula:

for samples of type III

; (8)

for samples of type IV

. (9)

The test results of each sample are recorded in the test Protocol (Appendix G), and the test results of batch samples in the summary report (Annex D).

Note — it is allowed the curve of hardening on relative deformation (shortening) .

6.10.3 the Order of sample testing is shown below.

Load the specimen to a predetermined load. Unload the sample to zero load and measure the final diameter of the specimen in two mutually perpendicular directions, and for the samples of a type III final height of the sample . The final diameter for the samples of type IV measure upset in the middle of the sample (at a distance of 0.5 m from face).

To determine the samples of a type III measure the diameters of the treated samples at both ends in two mutually perpendicular directions and set the arithmetic average of the final diameter of the ends and in the middle of the sample is measured, the maximum value of the final diameter of the upset billet , mm, is calculated by the formula

. (10)

The results of the measurements and averaged. The final cross-sectional area of the sample rounded off as given in table 2.

For samples of type IV one-time test is carried out until the disappearance of the ribs.

With the aim of achieving a higher degree of uniform deformation used a two-stage slump, the value of the logarithmic strain between rainfall should not be less than 0.45.

When two-stage test is carried out after the first upsetting perekachivanie samples for the formation of a cylindrical recess (type IV). The dimensions of the ribs of the sample chosen in table 1. The ratio of height of the sample re-drilled to the diameter accepted by the application A.

For samples of type III are allowed to apply the intermediate perekachivanie for two-stage separation, with a logarithmic degree of deformation between treads shall be not less than 0.45.

6.10.4 the flow Stress and the corresponding values of logarithmic deformations for given levels of loads determined by 6.10.2.

6.10.5 Build hardening curve (see figures 9, 10). Methods of processing experimental data are outlined in Annex E.

6.10.6 In justified cases (with a limited number of samples or when using the results for calculations of the processes associated with step loading) samples of type III are allowed to test with stepwise increasing load (figure 11). The results of the tests to construct the curve of hardening of the treated by regression analysis (see Annex E).

Figure 11 — testing for a given step increase in load

1 — loading; 2 — unloading

Figure 11 — testing for a given step increase in load

6.10.7 the Test specimens are considered invalid:

— when separation of the fillets in samples of type IV during loading;

— with the destruction of the sample for defects of metallurgical production (rassai, gas shells, slivers, etc.).

The number of test samples recognized as invalid instead of it should be the same.

6.11 in testing samples of all types comply with all the rules of technical security required when working on this equipment. Test samples of type IV fulfill the must fit (see Appendix C).

Annex a (informative). Determining the size of the samples III, IV types

APPENDIX A
(reference)

Samples of type III to construct the curve of hardening produce a height exceeding the diameter . For samples of type IV is allowed . The initial attitude should be as possible while ensuring longitudinal stability. The height of the sample is determined by the formula

, (A. 1)

where  — the rate of strain hardening;

 — coefficient of reduction of height (=0.5 — for samples of type III; a =0,76 — sample type IV).

The height of the sample after the determination by the formula (A. 1) rounded to the nearest whole number. Attitude to resharpen samples taken equal to 1.0.

Values for commonly used metals and alloys are given in table A. 1. The thickness of the flange (section 4) is taken as equal to 0.5−0.8 mm for samples of ductile and medium strength materials 1,0−1,2 mm — for brittle materials. Large values are chosen for the samples made from materials with high strength properties, and in the manufacture of samples for re-precipitation.


Table A. 1 — value of the indicator strain hardening in compression bar material

Material	The condition of the material		The indicator strain hardening
1 TECHNICALLY PURE METALS
Iron	Annealing the usual		0,27−0,28
Annealing in vacuum		0,23
Aluminium	Annealing		0,17−0,22
Copper	Annealing		0,47−0,49
Nickel	Annealing		0,36
Silver	Annealing		0,435
Zinc	Annealing		0,218
Molybdenum	Annealing recrystallization		0,04
Magnesium	Pressing		0,9
Tin	-		0,139
Uranium	-		0,3
2 CARBON STEEL
With a carbon content of 0.05−0.10%	Hot rolling		0,25−0,21
With a carbon content of 0.10% to 0.15%	Annealing		0,25−0,21
Incomplete annealing		0,21
Normalization		0,23
With a carbon content of 0,20−0,35%	Annealing		0,23
Incomplete annealing		0,19−0,185
Normalization		0,22−0,175
Hot rolling		0,22−0,18
With a carbon content of 0.40 to 0.60%	Annealing		0,20−0,17
Incomplete annealing		0,185−0,163
Normalization		0,195−0,18
Hot rolling		0,17−0,16
With a carbon content of 0.70−1.0 percent	Annealing		0,19−0,18
Incomplete annealing		0,177−0,163
Hot rolling		0,153−0,15
With a carbon content of 1.1 to 1.3%	Incomplete annealing		0,17−0,15
3 ALLOY STRUCTURAL AND TOOL STEEL
15X	Hot rolling		0,18−0,20
20X	Annealing		0,204
Normalization		0,191
Hardening+vacation at =650 °C		0,113
Hardening+vacation if =500 °C		0,112
35X	Hot rolling		0,166
40X	Annealing		0,153
Normalization		0,128
Hardening+leave in =600 °C		0,134
Hardening+leave in =400 °C		0,104
45KH	Hot rolling		0,148
20G	Annealing		0,225
Normalization		0,160
10G2	Annealing		0,19
65G	Hot rolling		0,156
15ХГ	Annealing		0,16−0,17
Hot rolling		0,14−0,15
40KHN	Annealing		0,144
35ХС	Annealing		0,175
Normalization		0,145
12KHN3A	Annealing		0,193
Normalization		0,174
Hardening+leave in =600 °C		0,1
Hot rolling		0,17
4ХНМА	Annealing		0,134
Normalization		0,123
Hardening+leave in =600 °C		0,1
Hot rolling		0.157 inch
30KHGSA	Annealing		0,17
Normalization		0,19
18HGT	Annealing		0,174
17ГСНД	Normalization+aging =500 °C		0,22
17ГСАЮ	Normalization		0,27
CVH	Annealing		0,23
5KHNV	Of 0.146
7X3	0,160
Х12Ф	0,135
3Х3В8Ф	0,165
R18	0,135−0,147
4 HIGH-ALLOY STEEL
20X13		Annealing		0,21
12KH18N9		Normalization		0,625
12X18H9T		Quenching in oil		0,370
Quenching in water		0,390−0,395
20Х13Н18		Quenching in oil		0,328
10X17H13M2T		Quenching in water		0,365
Austenitic steel type 09KH17N7JU, 08Н18Н10, 10Х18Н12, 10Х23Н18
17−7		Hardening		0,63−0,71
18−8		0,45−0,60
18−10		0,37−0,53
23−20		0,33−0,34
5 ALUMINUM ALLOYS
Amg2m		Annealing		0,19
AMg6		Annealing		0,26
D1		Annealing		0,16−0,17
Quenching+natural aging		0,26
Aging at t =180 °C		0,08
Aging at t =200 °C		0,10
1915		Hardening		0,27
Conditioning aging		0,235
Aging at maximum strength (stable state)		0,11
Pressing		0,134-of 0.146
AK4−1		Annealing		0,114
Quenching+aging		0,15
AV		Pressing		0,14−0,16
D20		Pressing		0,16−0,21
D16		Pressing		0,162−0,190
6 COPPER ALLOYS
Brass L63		Annealing		0,406
Brass LS59−1V		Annealing		0,277
CuZn15 Brass (15% Zn)		-		0,41
CuZn30 Brass (30% Zn)		-		0,51
Bronze ОФ7−0,25		Annealing		0,45−0,46
Bronze CuАl41 (41% Al)		-		0,565
7 TITANIUM ALLOYS
OT4		Annealing in vacuum		0,128
ВТ16		Annealing in vacuum		0,034

The height of flange , mm (section 4) determined by the formula*

, (A. 2)

where is the Poisson’s ratio, which values of some metals are given in table A. 2.
________________
* In the case of re-precipitation samples are made with the height of the ribs by 0.02−0.03 mm less than estimated.


Table A. 2 — Values of the Poisson’s ratios of metals and alloys

Name of metals and alloys
Carbon steel with high manganese content (15G, 20G, 30G, 40G, 50G, 60G, 20G2, 35G2)	0,22
Iridium	0,26
Steel 20X13, 30ХНМ	0,27
Austenitic steel	0,27−0,29
Iron, low carbon steel and high-alloy steel of grade 30X13, 20Н5, 30ХН3	0,28
Zinc, tungsten, hafnium, steel with high carbon content, steel 40ХН3	0,29
Chrome molybdenum	0,31
Cobalt	0,32
Aluminum, duralumin, Nickel, zirconium, tin	0,33
Titanium, magnesium alloys	0,34
Tantalum	0,35
Vanadium	0,36
Silver	0,37
Copper	0,37
Niobium, palladium, platinum	0,39
Gold	0,42
Lead	0,44
Indium	0,46

For samples with a =0.5−1.2 mm from metals and alloys =0,22−0,46 calculated values is shown in figure A. 1 and table A. 3.

Table A. 3 — the height of the collar

	mm
=0,5	=0,6	=0,8	=1	=1,2
0,22	0,138	0,166	0,221	0,276	0,331
0,23	0,147	0,176	0,235	0,294	0,353
0,24	0,156	0,187	0,250	0,312	0,374
0,25	0,165	0,198	0,264	0,330	0,396
0,26	0,174	0,209	0,279	0,349	0,419
0,27	0,184	0,221	0,294	0,368	0,441
0,28	0,194	0,232	0,310	0,387	0,464
0,29	0,203	0,244	0,325	0,407	To 0.488
0,30	0,213	0,256	0,341	0,426	0,512
0,31	0,223	0,268	0,357	0,446	0,536
0,32	0,233	0,280	0,373	0,467	0,560
0,33	0,244	0,292	0,390	0,487	0,585
0,34	0,254	0.305 per	0,406	0,508	0,610
0,35	0,264	0,317	0,423	0,529	0,635
0,36	0,275	0,330	0,440	0,550	0,660
0,37	0,286	0,343	0,457	0,572	0,686
0,38	0,297	0,356	0,475	0,594	0,712
0,39	0,308	0,369	0,492	0,615	0,739
0,40	0,319	The 0.383	0,510	0,638	0,765
0,41	0,330	0,396	0,528 which	0,660	0,792
0,42	0,341	0,410	0,546	0,683	0,819
0,43	0,353	0,423	0,565	0,706	0,847
0,44	0,364	0,437	0,583	0,729	0,874
0,45	0,376	0,451	0,602	0,752	Of 0.902
0,46	0,388	0,465	0,620	0,776	0,931

Figure A. 1 Dependence of optimal values of the height of the ribs from the Poisson’s ratio

Figure A. 1 Dependence of optimal values of the height of the ribs from the Poisson’s ratio

Approximately can be calculated by the formula

. (A. 3)

ANNEX B (reference). The types of hardening curves

APPENDIX B
(reference)

There are eight types of hardening curves based on the results of the compression testing (figure B. 1). The progress curves of hardening due mainly to the nature of metals and alloys (figure B. 1A, b, C, d, e), type and mode pre-heat and plastic treatment (figure B. 1E, f, K).

Figure B. 1 — Types of hardening curves

Figure B. 1 — Types of hardening curves

The most common is hardening curve, shown in figure B. 1A. This kind of hardening curves have heat-treated and hot-rolled carbon and alloy structural and tool steel, a high alloy steel, iron, aluminum and its alloys, copper and titanium and most of their alloys, light metals and a number of difficult-to-deform metals and their alloys. In these curves, the hardening, the flow stress increases relatively strongly in the initial stages of deformation, in the future, the intensity of hardening decreases gradually and then with increasing deformation almost does not change. For ductile metals and alloys, the intensity increasing with the increase smaller than for solid metals and alloys.

The second type of hardening curves (figure B. 1B) is characterized by high intensity of hardening, which may slightly decrease at high degrees of deformation. This type of curve is characteristic of the hardening of austenitic steels, some copper and titanium alloys.

The third type of hardening (figure B. 1B) describes the dependence of zirconium and alloy on its basis zircaloy-2. For such curves of hardening the intensity of hardening at small degrees of deformation is very small, and then increases sharply; the insignificant decrease in the intensity of hardening is manifested in the degrees of deformation close to collapse.

The fourth type of hardening curves (figure B. 1D) is characterized in that, after reaching the maximum value , its value with a further increase or decreases, or remains unchanged. This type of hardening curves set for zinc and its alloys with aluminum in the annealed condition (curve 2), quenched and aged condition (curve1) and for some aluminum alloys at high degrees of deformation.

Hardening curves presented in figure B. 1D, characteristic of superplastic materials. The curve for such materials is complex, with the manifestation of highs and lows (fifth curves of hardening).

Presented in figure B. 1E hardening curves (the sixth form) characteristic of various plastic alloys, has received a preliminary treatment pressure in a cold state at relatively small strains (about 0.1 to 0.15), and direction of the loads at preliminary and subsequent deformation of the opposite (e.g. drawing + sediment). The intensity change is smaller for alloys, which received a great degree of pre-deformation (curve 3compared to curve 1). Such curves hardening intensity increases with the increase in the whole range of degrees of deformation is less than that of the hardening curves of the first three types (figures B. 1A, b, C).

Hardening curves shown in figure B. 1Zh belong to the pre-deformed in a cold condition alloys with opposite direction of loads when pre-and post-deformation, plastic steels with large degrees of pre-strain (0,1−0,15), steels of medium and high strength, brass and bronze with high degrees of pre-strain.

Eighth appearance (figure B. 1) curve corresponds to the hardening of steels and some alloys based on it, has received a preliminary treatment in the form of cold plastic deformation, when the direction of load application in both strains is the same. More gentle the slope of the hardening curves (curves 3 and 4) corresponds to higher degrees of pre-strain. For such steels characterized by low growth rate with increasing .

Hardening curves of the first kind are well approximated by the dependence

. (B. 1)

With some approximation, the dependence (B. 1) describes the curves of hardening the second and third kind. It is recommended to use this relationship to approximate the curve of hardening of a fourth species in a range of degrees of deformation before the occurrence of a maximum on it.

Hardening curves of the sixth, seventh and eighth types with sufficient accuracy for practice can be linearisierung and then with some approximation, can be approximated by the equation

, (B. 2)

where  — extrapolated yield strength of previously deformed steels (intercept linearized straight line on the ordinate);

 — coefficient characterizing the slope of the linearized curves of hardening.

ANNEX b (recommended). Design fixtures for testing of samples in compression

THE APP
(recommended)

Figure V. 1 shows the Assembly drawing of the fixtures for testing in compression, which eliminates distortions between the sample and the deforming plate and to improve the accuracy of loading of the sample.

Allowed to use devices of other designs.

Figure B. 1 — Device for compression testing

1 — punch; 2 — guide Bush; 3 — base; 4 — supporting top plate; 5 — sample; 6 — samostoyatelnaya support with removable liner

Figure B. 1 — Device for compression testing

ANNEX G (recommended). TEST REPORTS SAMPLES OF I-IV TYPES

APPENDIX D
(recommended)

PROTOCOL
test samples I-III for evaluation of mechanical characteristics

The purpose of the test
Testing machine. Type
Sample. Type				. Hardness according to Brinell or Rockwell

Sample number				Load (kgf)					Characteristic, MPa (kgs/mm)

Attached to the Protocol diagram tests.

Tests conducted	Personal signature	Signature
Head. laboratory	Personal signature	Signature

PROTOCOL
testing of cylindrical specimens types III and IV to construct the curve of hardening

The purpose of the test
Testing machine. Type			. Sample. Type

Sample number

Hardness according to Brinell or Rockwell

mm

mm

mm

mm

mm

mm

N (kgf)

, MPa (kgs/mm)

Tests conducted	Personal signature	Signature
Head. laboratory	Personal signature	Signature

ANNEX D (recommended). THE CONSOLIDATED TEST REPORT OF THE SAMPLES I-IV TYPES FOR THE EVALUATION OF MECHANICAL CHARACTERISTICS AND PARAMETERS OF APPROXIMATING EQUATIONS OF THE CURVES OF HARDENING

APPENDIX E
(recommended)

The name of the test

Characteristics of the test material:

Brand and condition

The direction of the fibers

Stock type

Type and size of sample

The surface condition of the sample

Hardness according to Brinell or Rockwell

Type and main characteristics of testing machines and measuring equipment:

testing machine

strain gauge

transducer of displacements

measuring instruments and tools

Converter power

recording device

Test conditions:

Materials and hardness of the deforming plates (HB or HRC)

The speed of relative deformation,

Loading rate, MPa/(kgf/mm·s)

The speed of movement of the deforming plates, mm/s

Test results

Sample number

MPa (kgf/mm)

MPa (kgf/mm)

, MPa (kgs/mm)

MPa (kgf/mm)

, MPa (kgs/mm)

MPa (kgf/mm)

, MPa (kgs/mm)

, MPa (kgs/mm)

, MPa (kgs/mm)

Tests conducted	Personal signature	Signature
Head. laboratory	Personal signature	Signature

ANNEX E (recommended). Processing of the experimental data to construct the curve of hardening. Estimation of parameters of approximating equations

ANNEX E
(recommended)

1 When testing the batch samples

For each specific value experience on the same model. Hardening curves described by equations (figures B. 1A, b, C) or (figure B. 1E, f, K), are based on the results of the processing using the least squares method, all experimental points in the entire range of studied degrees of deformation. Treatment should be done on a computer. Thus for curves of hardening determine the parameters of approximating equations , , , .

Figure E. 1 — typical dependence of the strain hardening index n on the degree of deformation Epsilon (l)

Figure E. 1 — Typical dependence of the rate of strain hardening to the degree of deformation

In the case of processing the experimental data analytically, it is recommended to use reference books.

2 in a limited number of tests

With a limited number of experiments (five samples) hardening curves are based on handling diagrams of machine records by the lees of all test specimens to the final degree of deformation. expect for values equal to 0,01; 0,03; 0,05; 0,08; 0,1 and then every 0.05 until the final values of degree of deformation . For each value defined as average according (five points). The curves of hardening and further processing of experimental data carried out as when testing the batch samples.

3 the definition of the indicator strain hardening at small degrees of deformation in narrow range

For most metals and alloys the dependence is not a linear function (figure E. 1): with growth usually decreases , reaching high values for the almost constant value (figure E. 1A), or initially increasing, reaching a maximum and then decreases (figure E. 1B). And only in some cases is linear (figure E. 1a).

The first type of dependence (figure E. 1B) is typical for copper, carbon structural and tool steels, and a number of structural alloy steels.

Presented in figure E. 1B the dependence inherent to materials experiencing structural-phase transformations during deformation of austenitic steel, some brass. Almost not changing the value with growth (figure E. 1B) for iron, chromium constructional steels. For aluminum alloys depending on their chemical composition are observed in all three types of addiction .

In connection with a change with the growth for most metals and alloys, the need arises to define at small degrees of deformation in a narrow range. can be determined by processing the experimental data on a computer using the least squares method, however, the number of experimental points should be at least 8−10 in the considered range of degrees of deformation or calculated according to the formula

. (E. 1)

The electronic text of the document
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the official publication of the
Mechanical tests.
Calculations and strength tests:
SB. standards. — M.: STANDARTINFORM, 2005