RU2499246C2 - Method to determine strength characteristics of material and device for its realisation - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: device comprises a body with an electric motor and a reducer inside it; two parallel columns fixed on the body with a cross beam installed on it as capable of displacement along them together with mechanisms of its fixation on the columns and a tool fixed on it; a tool head, a mechanism of tool installation, a mechanism of tool feed and removal from the sample surface, a metre of normal movements of the tool, a sensor of normal force, a mechanism and a table for installation and thermal stabilisation of the sample; a mechanism of normal loading of the tool; an automated system of setting of a loading and unloading program, reading, recording and processing of test result information together with a personal computer. The device is additionally equipped with a mechanism of tangential displacement of the sample; a mechanism of sample rotation in the vertical plane; a mechanism of fine displacement of a sample in a vertical plane; a mechanism of accelerated displacement and fixation of the tool; a sensor for measurement of a tangential force; a mechanism of vertical displacement of the cross beam. The substance: a program is used to select a type of research and its completion from possible several automatically realised on one and the same device, such as strip-chart recording or stylus method for assessment of sample roughness; assessment of microhardness of sample surface; assessment of energy of plastic deformation activation; tribometric technique; forecasting of the residual resource; strip-chart recording and stylus method of sample surface rippling, and the selected research is carried out with the help of the device.

EFFECT: expansion of technical capabilities, simplification and acceleration of operations.

8 cl, 16 dwg

Description

The invention relates to mechanical engineering, and in particular to the determination of the strength characteristics of materials of machine parts under the fatigue fracture mechanism, as well as in the deformation of surface layers of material by friction, and can be used to assess their state parameters.

Similar methods are known for determining the strength characteristics of materials [1, 2], namely, that an indenter is inserted into the test material under load, the geometric parameters of the prints and furrows are measured, and then the strength characteristics of the material are determined.

Similar methods are implemented by a separate device and therefore are only suitable for determining a limited number of characteristics.

The closest in its technical essence as a prototype is a method for determining the strength characteristics of a material and a device for its implementation [3], which consists in scratching the prepared surface of the samples by the indenter, repeating the indenter passes, and estimating the volume of the material displaced by the indenter from the surface layer spent energy, then determine the characteristic of the material - the activation energy of the destruction of the surface layer, as the ratio of the spent energy to the amount of mother la displaced from the surface layer.

However, the prototype is limited in its technological capabilities, as it allows you to determine only certain characteristics of the material, limited by the device.

The inventive method is devoid of this drawback.

Known similar devices for implementing the method for determining the strength characteristics of a material [4, 5], comprising a housing, an indenter, an indenter loading mechanism, a column, an indenter longitudinal movement mechanism, an optical system, an information processing unit, a command device, a sample fixing mechanism, a locking unit.

Similar devices have a drawback: they are designed for certain operations, that is, they have limited technological capabilities, low productivity.

As a prototype, in its technical essence, the device [6] is the most suitable, containing a housing, a column, an indenter, an indenter loading mechanism, indenter longitudinal and lateral movement mechanisms, an information processing unit, a command device. The prototype device allows you to press the indenter tool, apply a scratch to the test surface of the sample and proceed to the next scratch, measure the indentation force of the indenter tool, the size of the scratch-groove, the height of the influx, the width and depth of the scratch. However, the prototype device has a drawback. It is limited in its technological capabilities. It is impossible to carry out all operations according to the claimed method for determining the strength characteristics of the material.

The specified disadvantage is absent in the claimed device.

The technical result of the present invention is to expand the technical capabilities, simplifying and speeding up operations.

[кгс/мм²], где D=h/0,14 [мкм] - размер диагонали отпечатка 4, m=F_N·10^-3·g^-1≈F_N·10^-2, [г] - эквивалентная масса навески; строят график зависимости Hµ=f(h); сохраняют результаты вычислений в памяти блока обработки информации. После выбора вида исследований - профилографирование - профилометрирование шероховатости поверхности образца при выборе требуемого режима исследования задают базовую длину трассы сканирования поверхности; устанавливают инструмент - алмазную иглу с углом при вершине 60° в державку; автоматически включают двигатель горизонтального перемещения каретки; перемещают инструмент - алмазную иглу по исследуемой поверхности в режиме сканирования (без приложения нормальной нагрузки) на величину базовой длины; одновременно на экране компьютера строят график зависимости «вертикальное перемещение инструмента - алмазной иглы - горизонтальное перемещение исследуемого образца» в режиме реального времени; при задании нескольких чисел заданных измерений действие повторяют заданное число раз; выводят на экран среднюю линию профиля, линии впадин и выступов, кривую опорной поверхности; рассчитывают и выводят на экран монитора параметры R2 - высоту шероховатости, Ra - среднеарифметическое отклонение, tm - шаг; найденные значения критериев профиля шероховатости исследуемой поверхности образца сохраняют в памяти блока обработки информации; возвращают каретку в исходное положение; поворачивают ручку фиксации инструмента - алмазной иглы в положение «хранение», приподнимая при этом подвеску; сохраняют результаты вычислений в памяти блока обработки информации. После выбора вида исследований - оценка энергии активации пластической деформации; выбирают требуемый критерий измерений - по заданной величине нормальной нагрузки или внедрения инструмента-индентора; вводят в рабочую программу в зависимости от выбора требуемого критерия измерений значение нормальной нагрузки или глубины внедрения инструмента-индентора при царапании, значение молярного объема материала исследуемого образца, числа измерений, требуемой длины царапины; устанавливают инструмента - четырехгранную пирамиду с углом при вершине 136° в державку; включают двигатель нормального нагружения; нагружают подвеску по нормали до заданной величины нормальной нагрузки или до заданной величины внедрения инструмента-индентора в поверхность исследуемого образца - в зависимости от выбора требуемого критерия измерений; включают двигатель горизонтального перемещения каретки; царапают инструментом-индентором поверхность исследуемого образца на заданную величину; одновременно измеряют силу царапания; вычисляют величину энергии активации пластической деформации; возвращают каретку в исходное положение; сохраняют текущее значение энергии активации пластической деформации в памяти блока обработки информации. После выбора вида исследований - прогнозирование остаточного ресурса задают начальное значение энергии активации пластической деформации поверхностного слоя и величину энергии активации разрушения материала поверхностного слоя; выбирают вид прогнозирования (по текущему значению энергии активации пластической деформации или по кинетике изменения энергии активации пластической деформации); при прогнозировании по текущему значению энергии активации пластической деформации определяют ожидаемое время наступления разрушения t_pec и остаточный ресурс материала δ по формулам:The technical result is achieved by the fact that scratches are made on the prepared surface of the samples by the indenter tool, the passes of the indenter tool are repeated, the volume of material displaced by the indenter tool from the surface layer is estimated, the energy expended at a given temperature of the sample, then the material characteristic is determined - the activation energy of surface fracture layer, as the ratio of energy expended to the amount of material displaced from the surface layer, using the selection program in the study and its conduct from the possible several automatically implemented on the same device as profiling-profiling of the roughness of the sample; microhardness assessment of a sample surface; assessment of the activation energy of plastic deformation; tribometry; prediction of residual life (at the current value or kinetics of changes in the activation energy of plastic deformation); profiling-profiling of the undulation of the surface of the sample; include a personal computer information processing unit, download a work program for selecting a type of study and its conduct; turn the knob of fixing the tool to the "measurement" position, moving the suspension away with the cam; fat-free and dried sample is placed on the table with the studied surface perpendicular to the axis of movement of the tool; install the appropriate tool in the holder; enter the required initial data and study modes into the work program for selecting the type of study and its conduct; press the "start" button of the window of the work program for selecting the type of study and its conduct; lower the traverse with the tool head until the tool touches the test surface of the sample, determining its moment of contact according to the readings of the sensor of vertical movements of the tool; the engine for horizontal movement of the carriage moves the carriage to the distance of the exit of the top of the tool from the deformed region of the investigated surface to zero readings of the sensor of vertical movements of the tool; implement the algorithm for further actions according to the result of the choice of research types. After choosing the type of research - assessment of the microhardness of the surface of the sample enter the required number of measurements, the magnitude of the normal load; install the tool - a standard Vickers diamond indenter (a tetrahedral pyramid with an angle at the apex of 136 °); include a loading engine; press on the free end of the flat spring of the suspension load sensor; at the same time, they build a graph of the dependence “normal load F _N [N] - the amount of penetration of the tool-indenter h [μm] into the test surface” (h = f (F _N )); simultaneously calculate the microhardness value by the formula $${\text{H}}_{\text{μ}}=\frac{\text{1854}\text{,four}\cdot \text{m}}{{\text{D}}^{\text{2}}}$$

[kgf / mm ² ], where D = h / 0.14 [μm] is the diagonal size of the print 4, m = F _N · 10 ^-3 · g ^-1 ≈F _N · 10 ^-2 , [g] is the equivalent mass hinges; plotting the dependence Hµ = f (h); save the results of the calculations in the memory of the information processing unit. After choosing the type of research - profiling - profiling of the roughness of the surface of the sample when choosing the desired research mode, set the base length of the surface scan path; set the tool - a diamond needle with an angle at the apex of 60 ° in the holder; automatically turn on the engine of horizontal movement of the carriage; move the tool - a diamond needle along the surface under investigation in the scanning mode (without applying a normal load) by the value of the base length; at the same time, a graph of the dependence “vertical movement of the tool — diamond needle — horizontal movement of the test sample” in real time is plotted; when setting several numbers of specified measurements, the action is repeated a specified number of times; display the middle line of the profile, the lines of the depressions and protrusions, the curve of the supporting surface; parameters R2 are calculated and displayed on the screen of the monitor — roughness height, Ra — arithmetic mean deviation, tm — step; the found values of the roughness profile criteria of the studied surface of the sample are stored in the memory of the information processing unit; return the carriage to its original position; turn the knob for fixing the tool - the diamond needle to the "storage" position, while raising the suspension; save the results of the calculations in the memory of the information processing unit. After choosing the type of research - assessment of the activation energy of plastic deformation; select the required measurement criterion - for a given value of the normal load or the introduction of the indenter tool; depending on the choice of the required measurement criterion, the value of the normal load or the penetration depth of the indenter tool when scratching, the molar volume of the material of the test sample, the number of measurements, the required length of the scratch are introduced; set the tool - a tetrahedral pyramid with an angle at the apex of 136 ° into the holder; turn on the engine of normal loading; load the suspension normal to a predetermined value of the normal load or to a predetermined amount of penetration of the indenter tool into the surface of the test sample, depending on the choice of the required measurement criterion; turn on the engine for horizontal movement of the carriage; scratch the surface of the test sample by the indenter tool by a predetermined amount; simultaneously measure the force of scratching; calculate the activation energy of plastic deformation; return the carriage to its original position; save the current value of the activation energy of plastic deformation in the memory of the information processing unit. After choosing the type of research - forecasting the residual life, the initial value of the activation energy of plastic deformation of the surface layer and the value of the activation energy of the destruction of the material of the surface layer are set; choose the type of prediction (according to the current value of the activation energy of plastic deformation or the kinetics of changes in the activation energy of plastic deformation); when predicting the current value of the activation energy of plastic deformation, determine the expected time of fracture t _pec and the residual life of the material δ by the formulas:

, $${\text{t}}_{\text{pec}}=\frac{\text{one hundred}}{\text{one hundred}-\text{δ}}{\text{t}}_{\text{exp}}$$

,

$$\text{δ}=\text{one hundred}\cdot \text{(one}-\frac{{\text{U}}_{\text{0}}-{\text{<figure-callout id="0" label="U" filenames="00000023.png,00000024.png" state="{{state}}">U</figure-callout>}}_{\text{0}}^{\text{out}}}{{\text{<figure-callout id="0" label="U" filenames="00000023.png,00000024.png" state="{{state}}">U</figure-callout>}}_{\text{0}}^{\text{cr}}-{\text{<figure-callout id="0" label="U" filenames="00000023.png,00000024.png" state="{{state}}">U</figure-callout>}}_{\text{0}}^{\text{out}}}\text{)}$$

where t _exp - the duration of the time the material in units of time; U ₀ , U ₀ ^ref , U ₀ ^cr - current, initial, critical (maximum permissible) value of the activation energy of plastic deformation of the material, respectively; when predicting the kinetics of changes in the activation energy of plastic deformation, a table of initial data is constructed containing the previously found values of the activation energy of plastic deformation of the material under study and the corresponding operating time values; choose the type of approximation (linear or non-linear); using a work program, a dependency is automatically built on the computer screen in the coordinates "running hours - activation energy of plastic deformation" approximated by the least squares method and horizontal lines corresponding to the initial and critical levels of activation energy of plastic deformation of the material; automatically determine the intersection point of the approximated dependence with a critical value of activation energy; the axis value at the intersection point is taken as the predicted value of the material production time corresponding to its destruction, the predicted value of the material production time is stored in the memory of the information processing unit. After choosing the type of research - tribometry, set the magnitude of the normal load, speed, amplitude and time of movement of the carriage; set the spherical indenter tool into the holder; applying a layer of lubricant to the surface of the test sample; automatically turn on the loading engine; press on the tool - a spherical indenter with a normal force to a predetermined value with fixing by the load sensor of the suspension with a normal force; turn on the longitudinal motion engine in the reciprocating motion mode with a given speed, amplitude and test time; measure the friction force according to the readings of the tangential force sensor, the normal force acting on the tool - indenter, the displacement of the tool-indenter relative to the surface of the test sample, the linear wear on the difference of the readings of the sensor of vertical displacements of the tool-indenter; return the tool - the indenter and the carriage to its original position; save the result of the calculations in the memory of the information processing unit. After choosing the type of research - profiling - profilometry of the undulation of the surface of the sample, when choosing the desired research mode, specify the length of the scan path of the surface of the sample; set the tool - a diamond needle with an angle at the apex of 60 ° in the holder; automatically turn on the engine for horizontal movement of the table along with the sample by the length of the scan path (without applying a normal load); simultaneously with the movement of the sample, a graph is plotted on the computer screen of the dependence "vertical movement of the tool - horizontal movement of the test sample" in real time; when setting several numbers of specified measurements, the action is repeated a specified number of times; display the middle line of the profile, the line of depressions and protrusions; calculate the parameters W _Z - wave height S _W - wave step; the found values of the criteria for the undulation profile of the investigated surface of the sample are stored in the memory of the information processing unit; return the carriage and the tool - the diamond needle to its original position; turn the knob for fixing the tool - the diamond needle to the "storage" position, while raising the suspension; save the results of the calculations in the memory of the information processing unit.

A device for determining the strength characteristics of a material, comprising a box-shaped hollow body with an electric motor and a gearbox inside it; two parallel columns mounted on the casing with installed on them with the possibility of moving a traverse along them together with mechanisms for fixing it on the columns and a tool fixed on it; a tool head, a tool mounting mechanism, a mechanism for bringing the tool in and out of the sample surface, a measuring instrument for normal tool movements, a normal force sensor, a mechanism and a table for installing and thermally stabilizing the sample; mechanism of normal tool loading; an automated system for setting a program for loading and unloading, reading, writing and processing information from test results together with a personal computer, while it is additionally equipped with a mechanism for tangential movement of the sample; the mechanism of rotation of the sample in a vertical plane; the mechanism of thin movement of the sample in a vertical plane; a mechanism for accelerated movement and fixation of the tool; tangential force sensor; the mechanism of vertical movement of the traverse; the mechanism and the table for installing and thermally stabilizing the sample are made in the form of a table and a plate mounted on the device’s body, interconnected by a tangential movement mechanism of the sample, made, in turn, in the form of a lower case connected to the plate with the possibility of moving along its longitudinal guiding by means of a stepper motor located in the lower case, and a rack and pinion gear, the rack gear of which is fixed to the rotor of the stepper motor, and the rail on the plate, and the mechanism a sample gate in a vertical plane, fastened together by a table made in the form of an upper wedge and a lower wedge mounted on the upper case with the possibility of moving along its guides by rotating the spindle handle fixed in the bearing of the upper case and connected with the threaded hole of the lower wedge; moreover, the upper wedge is connected by means of a flat and twisted spring to the lower case with the possibility of rotation relative to it by means of a sample rotation mechanism in a vertical plane, consisting of a handwheel-screw, which can rotate in a nut fixed on the lower case and abut against the heel fixed with a spherical end in the upper case; and the mechanism of vertical movement of the traverse is made in the form of a stepper motor, a gearbox, including a belt drive, an intermediate shaft, two worms at its ends and two worm gears on two lead screws, passed inside the corresponding two columns and inside the case, two lead nuts mounted on two cradles rigidly fixed to the traverse, mounted on the respective columns in a movable landing with the possibility of fixing on them by means of the traverse fixing mechanisms; the mechanism of accelerated movement and fixation of the tool is made in the form of a disk cam and a handle for its rotation; the mechanism of normal loading of the tool and the mechanism of tangential movement of the tool are made in the form of a carriage suspended on pairwise plane-parallel springs with the possibility of movement, in two mutually perpendicular directions, by means of the respective two perpendicularly mounted linear step motors.

Distinctive features of the method: there is no need to have several different devices, operations for setting up and adjusting each type of study from the possible six, automatically implemented on the same device, disappear: evaluation of the microhardness of the sample; profiling-profiling of the surface roughness of the sample; assessment of the activation energy of plastic deformation; tribometry; prediction of residual life; profiling-profiling of the undulation of the surface of the sample. It is easy to go to any of the six types of research by grouping the same operations common to each type of research, which automatically commands the command device according to the contents of the work program.

Distinctive features of the device: the mechanism of tangential movement of the sample is additionally introduced; the mechanism of rotation of the sample in a vertical plane; tool unloading retraction mechanism; traverse movement mechanism; the mechanism of normal loading of the tool and the mechanism of tangential movement of the tool are differently implemented.

A comparative analysis of the method and device with known technical solutions shows that in the known technical solutions there are no distinguishing features of the proposed inventions, allowing to solve a new technical problem. Therefore, these symptoms are significant.

When determining the hardness of the surface 1 of sample 2 (Figure 1), tool 3, in this case, an indenter, under the influence of normal force F _N has the ability to penetrate into sample 2 by a value of h. The imprint 4 on the surface 1 has a rectangular shape with a size D of the diagonal. In this case, it is possible to plot a dependence of the depth h of the indent 4 on the normal force F _N transmitted to the indenter tool, i.e.

$$\text{h}={\text{f (F}}_{\text{N}}\text{)}\text{.}\text{(one)}$$

Indenter - a tetrahedral pyramid with an angle of 136 ° (Vickers diamond indenter). At the same time, it is possible to determine the microhardness value H for each value of h using the well-known formula

$${\text{H}}_{\text{μ}}=\frac{\text{1854}\text{,four}\cdot \text{<figure-callout id="2" label="m D" filenames="00000020.png,00000021.png" state="{{state}}">m </figure-callout>}}{{\text{D}}^{}}\text{,}\text{[to}{\text{gf / mm}}^{\text{2}}\text{]}\text{,}\text{(2)}$$

[мкм]- размер диагонали отпечатка 4,Where $$\text{D}\approx \frac{\text{<figure-callout id="0" label="h" filenames="00000023.png,00000024.png" state="{{state}}">h</figure-callout>}}{\text{0}\text{.fourteen}}$$

[μm] - the diagonal size of the print 4,

m = F _N · 10 ^-3 · g≈F _N · 10 ^-2 , [g] is the equivalent mass of the sample for installing the indenter tool.

Based on (2), it is possible to construct a dependence

$${\text{H}}_{\text{μ}}=\text{f (h)}\text{,}\text{(3)}$$

reflecting the gradient of the mechanical properties of the sample along the depth h of indent 4. When evaluating the activation energy of plastic deformation, it is also possible to use the standard Vickers 3 diamond indenter (Figure 2) with an angle at the vertex of 60 ° of the tetrahedral pyramid. The tool-indenter is notified of the normal force F _N to a predetermined value. Sample 2 can move in the longitudinal direction. A scratch 4 of a given depth h is formed on sample 2. Simultaneously with scratching, it is possible to measure the scratching force F and calculate the activation energy of plastic deformation.

When evaluating the tribotechnical properties of the material of the surface layer of sample 2, the tool 3 — the spherical indenter, is informed of the normal load F _N to a predetermined value. Sample 2 (Figure 3) is informed of a predetermined speed V and amplitude of movement. In this case, the friction force Fτ acts. A scratch of depth h occurs on sample 2. The amount of linear wear is defined as the difference between the current and initial readings of the sensor of vertical movements of the tool-indenter 3.

When assessing the roughness of the profilogram of surface 1 (Figure 4), it is possible to use a tool - a diamond needle 3 with an angle at the apex of 60 °. She can inform longitudinal movement with a given speed V for a given length equal to a given base length in the range of 0.25 ... 8 mm. In this case, the normal force is zero, that is, F _N = 0.

When assessing the waviness of the surface 1 of sample 2 (Figure 5), it is possible to use a tool - a diamond or carbide needle 3 with a spherical end. Only normal movement can be reported to it, and longitudinal movement at a given speed over the entire given length of surface 1 of sample 2 can be given to sample 2.

When evaluating the prediction of the residual resource of the material of the surface layer of the sample, it is possible to predict the activation energy of plastic deformation from the current value, or the kinematics of the change in the activation energy of plastic deformation.

When using the first option, that is, predicting the current value of the activation energy of plastic deformation, it is possible to determine the expected time of fracture _tres and the residual life of the material 5 as a percentage of the previous operating time

$${\text{t}}_{\text{pec}}=\frac{\text{one hundred}}{\text{one hundred}-\text{δ}}{\text{t}}_{\text{exp}},(\mathrm{four})$$

$$\text{δ}=\text{one hundred}\cdot \text{(one}-\frac{{\text{U}}_{\text{0}}-{\text{<figure-callout id="0" label="U" filenames="00000023.png,00000024.png" state="{{state}}">U</figure-callout>}}_{\text{0}}^{\text{out}}}{{\text{<figure-callout id="0" label="U" filenames="00000023.png,00000024.png" state="{{state}}">U</figure-callout>}}_{\text{0}}^{\text{cr}}-{\text{<figure-callout id="0" label="U" filenames="00000023.png,00000024.png" state="{{state}}">U</figure-callout>}}_{\text{0}}^{\text{out}}}\text{)}\text{(5)}$$

, $${\text{U}}_{\text{0}}^{\text{кр}}$$

- текущее, исходное, критическое (предельно допустимое) значение энергии активации пластической деформации материала, соответственно.where t _exp - the duration of the time the material in units of time; U ₀ $${\text{U}}_{\text{0}}^{\text{out}}$$

, $${\text{<figure-callout id="0" label="U" filenames="00000023.png,00000024.png" state="{{state}}">U</figure-callout>}}_{\text{0}}^{\text{cr}}$$

- current, initial, critical (maximum permissible) value of the activation energy of plastic deformation of the material, respectively.

As the current value of the activation energy of plastic deformation, the last measured value of the activation energy of plastic deformation using the device is taken.

If we predict from the kinetics of changes in the activation energy of plastic deformation (if there is data on the initial portion of the kinetics of accumulation of activation energy of plastic deformation of the test material), then it is possible to construct a table of initial data that includes previously determined values of the activation energy of plastic deformation related to this material and operating time values corresponding to them. It is possible to select the type of approximation: linear or nonlinear. The program according to the experimental data of the table has the ability to automatically build on the computer screen a dependence in the coordinates "running hours - activation energy of plastic deformation", approximated using the least squares method. Also, horizontal lines corresponding to the initial and critical energy levels of activation of plastic deformation of the material can be displayed on the screen. The accuracy of calculating the operating time is up to 1 s., The activation energy is up to 0.1 kJ / mol. The coefficients of a linear approximation of the form P1 (x) = a ₀ + a ₁ · x can be determined from a system of equations:

$$\begin{array}{l}(n+\mathrm{one})\cdot a_0+\left[{\displaystyle \sum _{i=0}^n{x}_i}\right]\cdot a_{\mathrm{one}}={\displaystyle \sum _{i=0}^n{y}_i;}\\ \left[{\displaystyle \sum _{i=0}^n{x}_i}\right]\cdot a_0+\left[{\displaystyle \sum _{i=0}^n{x}_i^2}\right]\cdot a_{\mathrm{one}}={\displaystyle \sum _{i=0}^n{y}_i\cdot x_i.(6)}\end{array}$$

The coefficients for a nonlinear approximation of the form P2 (x) = a ₀ + a ₁ · x + a ₂ · x ₂ can be found from a system of other equations:

$$\begin{array}{l}(n+\mathrm{one})\cdot a_0+\left[{\displaystyle \sum _{i=0}^n{x}_i}\right]\cdot a_{\mathrm{one}}+\left[{\displaystyle \sum _{i=0}^n{x}_i^2}\right]\cdot a_2={\displaystyle \sum _{i=0}^n{y}_i;}\\ \left[{\displaystyle \sum _{i=0}^n{x}_i}\right]\cdot a_0+\left[{\displaystyle \sum _{i=0}^n{x}_i^2}\right]\cdot a_{\mathrm{one}}+\left[{\displaystyle \sum _{i=0}^n{x}_i^3}\right]\cdot a_2={\displaystyle \sum _{i=0}^n{y}_i\cdot x_i,(7)}\\ \left[{\displaystyle \sum _{i=0}^n{x}_i^2}\right]\cdot a_0+\left[{\displaystyle \sum _{i=0}^n{x}_i^3}\right]\cdot a_{\mathrm{one}}+\left[{\displaystyle \sum _{i=0}^n{x}_i^{\mathrm{four}}}\right]\cdot a_2={\displaystyle \sum _{i=0}^n{y}_i\cdot x_{\mathrm{<figure-callout\; id="2"\; label="i"\; filenames="00000020.png,00000021.png"\; state="\{\{state\}\}">i</figure-callout>}}^2;}\end{array}$$

where a ₀ , a ₁ , a ₂ - approximation coefficients; n + 1 is the number of experimental points in the coordinates "activation energy of plastic deformation - running hours"; x - material production time; y are the experimental values of the activation energy of plastic deformation obtained from the approximated dependences of the first and second order, respectively.

It is possible to automatically determine the intersection point of the approximated dependence with a critical value of activation energy. The value of the axis at the intersection point indicates the predicted value of the material production time corresponding to the moment of its destruction.

Description of the method and device in statics.

To implement the possible six operations are measuring and actuating systems of the device (Fig.6). The measuring system of the results of the impact on the sample 1 of the tool 3 includes: tangential force sensor 5; normal force sensor 6; vertical (normal) displacement sensor 7; sensor of horizontal (tangential) displacements 8; an amplifier block 9, the input of which can receive signals from sensors 5 ... 8, an analog-to-digital converter 10, connected at the input to the output of the amplifier block 9, and at the output, to the input of the computer 11.

The executive system contains a driver block 12, which is able to receive control signals from the computer 11 at the input, and connected to the actuating elements at the output. As actuating elements, it is possible to use stepper motors, including a normal loading motor 13, a carriage displacement motor 14, a traverse vertical displacement motor 15, a stage 17 displacement motor 16 (the motor 16 is conventionally shown without a gearbox).

The structural arrangement of the device shown in Fig.7-11. The device also consists of a housing 18 (Figs. 7, 8, 9), a box-shaped hollow shape, on which two parallel columns 19 are installed, hollow with vertical grooves. On the columns 19, the sprockets 20 are able to move with the traverse 21 fixedly on them and the traverse 21 fixing mechanisms on the columns 19. The traverse 21 fixing mechanisms contain handles 22, screws 23 and clips 24. A tool head 25 is installed on the traverse 21, closed by a casing 26. The housing 18 inside contains a drive to move the traverse 21 along the columns 19, including a stepper motor 27 mounted on an elbow 28, a belt drive 29, 30, 31 on the shaft 32 with worms 33 at its ends, engaged with worm gears 34. Worms The primary gears 34 are mounted on vertical screws 35 screwed into threaded holes in the spiders 20. Vertical screws 35 are mounted on bearings in the columns 19 for rotation. A plate 36 is installed on the body 18, a supporting mechanism and a table for installing and thermally stabilizing the sample (not shown conditionally), stage 17, the mechanism for rotating the sample in a vertical plane, the mechanism of tangential (longitudinal) movement of the sample. The tangential movement of the sample is made in the form of a lower case 37 connected to the plate 36 with the possibility of movement along its longitudinal guides (not shown conditionally) by means of a stepping motor 16 located in the lower case 37 and a rack and pinion gear, the pinion gear 38 of which is mounted on the rotor 39 a stepper motor 16, and the rail 40 - on the plate 36. The mechanism of normal movement of the sample in a vertical plane, fastened with a table 17, is made in the form of an upper wedge 41 and a lower wedge 42 installed on the upper case 43 with the possibility of moving along its guides (not shown conditionally), by rotation of the handle 44 of the lead screw 45, mounted in the bearing 46 of the upper case 43 and connected with the threaded hole of the lower wedge 42. In the mechanism of rotation of the sample in the vertical plane, the upper case 43 connected by means of a flat 47 and twisted 48 springs to the lower case with the possibility of rotation relative to it by means of a sample rotation mechanism in a vertical plane, consisting of a handwheel-handle 49 of a screw 50 having zmozhnost rotation in the nut 51 fixed to the lower housing 37 and abut a spherical end heel 52, attached to upper housing 43. The tool head 25 is designed to install the tool 3 (11) on the tool holder 53 by means of screws. The holder 53 is connected to the suspension 54. The suspension 54 is resiliently suspended on the carriage 55 by means of two pairs of flat springs 56 and 57. The springs 56 enable the suspension 54 to move in parallel (vertical) direction and the springs 57 in the horizontal (tangential) direction, respectively .

Tool 3 has the ability to carry out the named movements by means of two linear stepper motors 13 and 14 having the ability to move the carriage 55 in two mutually perpendicular directions: vertically and horizontally, respectively.

The tool head 25 is equipped with a mechanism for the normal movement of the tool 3, consisting of a disk cam 58, which has the ability to rotate on its own axis 59 under the action of the handle 60.

Description of the method and device in dynamics.

They turn on the device’s power supply from a single-phase AC network of industrial frequency. Include the information processing unit, implemented on the basis of a personal computer 11. Download the work program. Turn the knob 60 of the fixation of the tool 3 to the "measurement" position. In this case, the cam 58 is diverted from the suspension 54, freeing it. Suspension 54 is suspended from a system of four plane-parallel springs 56, 57.

The sample 2 to be tested, after degreasing and drying, is installed on the table 17 so that the test surface 1, using the mechanism of rotation of the sample in a vertical plane (handle 49), occupies a horizontal position under the tool. Using the work program, select the type of test from among the methods implemented by the device:

- preparation for testing (private algorithm A);

- microhardness assessment (private B algorithm);

- roughness assessment during profiling, profiling (algorithm private B);

- assessment of the activation energy of plastic deformation (private algorithm G);

- assessment of tribological properties of the material (private algorithm D);

- prediction of residual life (private algorithm E);

- assessment of waviness during profiling-profiling (algorithm private F).

(блок 5); максимальную нормальную нагрузку F_Nmax (блок 6); критическое значение энергии активации пластической деформации $${\text{U}}_{\text{0}}^{\text{кр}}$$

(блок 7); ставится вопрос: следует ли калибровать датчик вертикальных перемещений? (блок 8). Если да, то фиксируют напряжение, соответствующее «нулевому» уровню инструмента-индентора (блок 9); опускают инструмент-индентор на 10 мкм и фиксируют соответствующее напряжение (блок 10); рассчитывают калибровочные коэффициенты датчика вертикальных перемещений (блок 11); ставят вопрос: следует ли выйти из режима подготовки к испытаниям? (блок 12). Если да, то выводят на печать (блок 96). Если нет, то следует возврат к началу алгоритма А. Если в блоке 8 получают отрицательный ответ, то ставится второй вопрос: калибровать ли датчик тангенциальной силы? (блок 13). Если да, то фиксируют напряжение, соответствующее «нулевому» уровню тангенциальной силы (блок 14); нагружают датчик силой 1Н и фиксируют соответствующее напряжение (блок 15). Рассчитывают калибровочные коэффициенты датчика тангенциальной силы (блок 16). Если следует выйти из режима подготовки к испытаниям (блок 12), то выводят на печать (блок 96), если нет, то возвращаются на начало частного алгоритма А. Если в блоке 13 получают отрицательный ответ, то ставят третий вопрос: Калибровать ли датчик нормальной силы? (блок 17). Если да, то фиксируют напряжение, соответствующее «нулевому» уровню нормальной силы (блок 18). Нагружают датчик силой 1Н и фиксируют соответствующее напряжение (блок 19). Рассчитывают калибровочные коэффициенты датчика нормальной силы (блок 20). Снова ставится вопрос о выходе из режима подготовки к испытаниям? (блок 12). Если да, то вывод на печать (блок 96). Если нет, то следует возврат к началу алгоритма А. Если в блоке 17 получают отрицательный ответ, то следует возврат к началу алгоритма А.When implementing the private algorithm A: enter the molar volume of the material V _m (block 4); the initial value of the activation energy of plastic deformation $${\text{U}}_{}^{}$$$${}_{\text{0}}^{\text{out}}$$

(block 5); maximum normal load F _Nmax (block 6); critical value of activation energy of plastic deformation $${\text{U}}_{}^{}$$$${}_{\text{0}}^{\text{cr}}$$

(block 7); the question is: should the vertical displacement sensor be calibrated? (block 8). If yes, then fix the voltage corresponding to the "zero" level of the tool-indenter (block 9); lower the indenter tool by 10 μm and fix the corresponding voltage (block 10); calculate the calibration coefficients of the vertical displacement sensor (block 11); pose the question: should I exit the test preparation mode? (block 12). If yes, then print (block 96). If not, then return to the beginning of algorithm A. If in block 8 you get a negative answer, then the second question is posed: should the tangential force sensor be calibrated? (block 13). If yes, then fix the voltage corresponding to the "zero" level of tangential force (block 14); load the sensor with a force of 1H and fix the corresponding voltage (block 15). Calculate the calibration coefficients of the tangential force sensor (block 16). If you want to exit the test preparation mode (block 12), then print it (block 96), if not, then return to the beginning of the private algorithm A. If you get a negative answer in block 13, then the third question is posed: Is the sensor calibrated normal strength? (block 17). If yes, then fix the voltage corresponding to the "zero" level of normal force (block 18). The sensor is loaded with a force of 1 N and the corresponding voltage is recorded (block 19). The calibration coefficients of the normal force sensor are calculated (block 20). Again, the question arises of leaving the test preparation mode? (block 12). If so, print output (block 96). If not, then return to the beginning of algorithm A. If in block 17 you get a negative answer, then you should return to the beginning of algorithm A.

When implementing private algorithm B, the maximum value of the depth of implementation of the indenter tool is entered (block 23); turn on the carriage displacement motor and shift the indenter tool forward by 20 μm (block 24); zero the readings of the vertical displacement sensor (block 25); turn on the engine of normal loading (block 26); collect data (during loading) from the sensors of vertical displacements of the tool-indenter and normal load on the tool-indenter with the output of values to the monitor (block 27); calculate and display on the monitor screen a plot of microhardness changes in depth (block 28). If the penetration depth has reached a predetermined value (block 29), then the indenter tool (block 30) and printing output (block 96) are unloaded. If not, they find out: has the load reached its maximum value? (block 31). If so, unload the indenter tool (block 30) and print (block 96).

If not, then return to the calculation of the plot of the microhardness changes in depth (block 28).

When implementing a private algorithm B: enter the value of the base length (block 34); turn on the carriage moving engine and shift the tool — the diamond needle forward by 20 microns (block 35); zero the readings of the vertical displacement sensor (block 36); include a carriage displacement engine (block 37); collect data from the sensor of vertical movements of the tool - a diamond needle (in the process of carriage movement) with a horizontal step of 1 μm and display the profilogram on the monitor screen (block 38). Find out: the carriage has reached the specified base length? (block 39). If so, then return the carriage to its original position (block 40); calculate and display the middle line of the profile, the line of depressions and protrusions (block 41); calculate and display the curve of the supporting surface (block 42); calculate and display on the monitor screen the parameters Rmax, Rp, Rz, Ra, tm, Rpk, RVk (block 43); save the received data in a file (block 44); printing (block 96). If not (block 39), then return to block 38.

When implementing private algorithm D: enter the maximum scratching depth and the length of the scratch (block 47; turn on the carriage displacement motor and move the indenter tool forward by 20 μm (block 48; zero the readings of the vertical displacement sensor of the indenter tool (block 49; turn on the normal loading motor tool-indenter (block 50); collect data from the sensor of vertical displacement (during loading) and normal load (block 51); if the penetration depth has reached a predetermined value (block 52), then turn off the engine but indenter loading and turn on the carriage displacement engine (block 53); collect data from sensors of vertical displacements, normal and tangential loads, calculate the value of activation energy of plastic deformation (block 54); display sensor readings and calculated values of activation energy on the monitor screen (block 55 ); unload the indenter tool (block 56); return the carriage to its original position (block 57); save the received data (block 58); print (block 96). If in block 52 the answer is no, then when the load reaches its maximum value (block 59) they go to block 53. If in block 59 they get a negative answer, then they return to block 51 and continue collecting data.

When implementing the private algorithm D: enter the amplitude of displacements, the number of double strokes of the tool - a spherical tip, normal load, maximum allowable linear wear (block 62); turn on the engine of normal loading, load the tool - a spherical tip to a predetermined value (block 63);

turn on the carriage displacement engine, shift the tool — the spherical tip forward by 20 microns (block 64); zero the readings of the vertical displacement sensor (block 65); include a carriage displacement engine in the reciprocating motion mode with a predetermined amplitude (block 66); collect data from sensors of vertical displacements, normal and tangential loads (block 67); display data on normal load, friction force and linear wear on the monitor screen (block 68); if the number of double strokes has reached a predetermined value (block 69), then the carriage is returned to its original position and the carriage displacement motor is turned off (block 70); save the received data in a file (block 71); print (block 96); if in block 69 they get a negative answer, they ask the second question (block 72): did the linear wear reach the set value? If so, then continue - returning the carriage to its original position, etc. (block 70). If not, then return to block 67.

When implementing a particular algorithm E: they pose the question of choosing a prediction mode — according to the kinetics of changes in the activation energy of plastic deformation? (block 74). If the answer is yes, the current values of the activation energy of plastic deformation and the corresponding values of the operating time of the test sample are entered (block 75); approximate the experimental data by the least squares method, find the coefficients of the approximated dependence (block 76); the dependence “activation energy of plastic deformation - running hours” is displayed on the monitor screen, the initial and critical level of activation energy of plastic deformation for a given material, experimental points, and an approximated curve are displayed on it (block 77); extrapolate the approximated curve to the intersection with the critical level of activation energy of plastic deformation, at this point find the corresponding operating time (block 78); calculate the predicted residual resource of the material in production units (block 79); save the received data in a file (block 80); print (block 96). If the answer is no, the current value of the activation energy of plastic deformation is displayed in block 74 (the last experimental value found is entered - by default) (block 81); calculate the predicted residual resource of the material in percent (block 82); go to block 80 - saving data in a file and printing (block 96).

When implementing the private algorithm W, the surface scanning length is entered (block 85); turn on the carriage moving engine, shift the tool — the diamond needle forward by 20 microns (block 86); zero the readings of the vertical displacement sensor (block 87); turn on the engine moving the table with the sample (block 88); collect data from the sensor of vertical movements of the tool - a diamond needle with a horizontal step of 10 microns, display a waveogram on the monitor screen (block 89); if the movement of the table with the sample has reached a predetermined value? (block 90), then return the table with the sample to its original position (block 91); calculate and display on the monitor screen lines of the peaks, the middle profile, the line of troughs (block 92); calculate and display on the monitor screen the parameters W ₂ , S _B (block 93); save the received data in a file (block 94), print it (block 96). If a negative response is received in block 90, then they are returned to block 89.

Examples of the implementation of the proposed method and device.

The surface quality of the silver-plated bronze washer of the sealed drill bit support was investigated. The coating is nanostructured silver-diamond (thickness 20 microns), the base is BrB2 beryllium bronze GOST 18175-78 (hardness after aging HB 350), the sublayer is copper (thickness 1 micron). Washer dimensions: outer diameter - 50 mm, hole diameter - 20 mm, thickness - 2.5 mm.

We installed the washer on the device’s table, grabbing the washer on two opposite sides with plasticine to exclude tangential movements of the washer on the table during testing. They turned on the device, started the computer and warmed up for 15 minutes. They started the working program on the computer, and the main window of the working program opened, on which the main menu with options for choosing the options for the device’s functioning is shown: “Preparing for testing”; "Assessment of microhardness"; "Profiling - roughness"; "Sclerometry"; "Tribometry"; "Resource Prediction"; "Profiling - waviness"; "Close the program." The portal bar was lowered until the indenter touched the surface of the washer. Reset the vertical displacement sensor.

Example No. 1 of the implementation of the private algorithm “A”.

They included the test preparation mode. They entered into the corresponding windows of the work program: the molar volume of silver V _m = 10300 kJ / mol; the initial value of the activation energy of plastic deformation u _n = 64 kJ / mol; maximum normal load on the indenter tool F _Nmax = 3 N; the critical value of the activation energy of plastic deformation u * = 110 kD / mol. Saved the entered data in computer memory. They clicked on the “Main Menu” button and went to the main window of the work program.

Example No. 2 of the implementation of the private algorithm "B".

The microhardness assessment mode was turned on. A tool was installed in the holder - a standard Vickers diamond tip with a square base and an inter-facet angle at an apex of 136 °. We introduced the value of the penetration depth of the tool - indenter h = 3 μm. Clicked on the "Start" button. The device automatically moved the indenter 20 μm to the left and zeroed the readings of the vertical displacement sensor. Then, the engine of normal loading turned on automatically. In this case, the dependence of the microhardness Нµ on the penetration depth of the tool-indenter h began to be built on the computer screen. After reaching the specified value h = 3 μm, the normal loading engine stopped and began to return to its original state until the tool - indenter was completely unloaded. The microhardness at a depth of 1 μm was 102 kgf / mm ² , at a depth of 2 μm - 87 kgf / mm ² , at a depth of 3 μm - 85 kgf / mm ² . Saved the data in computer memory. They clicked on the “Main Menu” button and went to the main window of the work program.

Example No. 3 of the implementation of the private algorithm "Zh".

We turned on the mode of profiling waviness. A tool was installed in the holder - a spherical steel indenter (⌀ 3 mm). Move the table with the sample 1 mm to the right relative to the indenter. In the dialog box, we selected the waveogram construction mode. Enter the scan length of the surface L = 20 mm and click on the "Start" button. The device automatically moved the tool 20 μm to the left and reset the vertical encoder to zero. Then the device automatically scanned the profile of the surface of the washer for 37 seconds (along the chord). In the process of scanning, a waveogram of the surface was built on a computer screen. After the scan is completed, the instrument returned to its original state. On the monitor screen, the average profile line, the lines of the peaks and troughs, and the parameters of the undulation of the surface of the washer were automatically constructed: the height of the undulation W _Z = 4.2 μm; waviness step S _W = 5431 μm. Saved the received data in computer memory. They clicked on the “Main Menu” button and went to the main window of the work program.

Example No. 4 of the implementation of the private algorithm "B".

We switched on the profiling mode - roughness. We installed a tool in the holder - a conical indenter with an angle at the apex of 60 °. Move the table with the sample 1 mm to the right relative to the indenter tool. In the dialog box, the waveogram construction mode was abandoned. Enter the base length l _b = 1.6 mm and click on the "Start" button. The device automatically scanned the surface profile for 3 seconds. During scanning, a surface profilogram was built on a computer screen. After the scan is completed, the instrument returned to its original state. The curve of the supporting surface and the roughness parameters of the washer surface were displayed on the monitor screen: R _max = 24 μm; R _p = 1.3 μm; R _Z = 1.1 μm; R _a = 0.3 μm. Saved the received data in computer memory. They clicked on the “Main Menu” button and went to the main window of the work program.

Example No. 5 of the implementation of the private algorithm "G".

We included the sclerometry mode. A tool was installed in the holder - a standard Vickers diamond tip with a square base and an inter-facet angle at an apex of 136 °. We moved the table with the sample 1 mm to the right relative to the tool - indenter. We entered the values of the depth of scratching h = 3 μm, the length of the scratch L _c = 400 μm and clicked on the "Start" button. The device automatically moved the indenter tool 20 microns to the left and zeroed the readings of the vertical displacement sensor. Then, the engine of normal loading automatically turned on, and on the computer screen the display of the readings of the normal force sensor began. After reaching the specified value of the depth of penetration of the tool-indenter h = 3 μm, the engine of normal loading stopped. Next, the carriage displacement motor automatically turned on and began to move the indenter tool to the left by a predetermined value of the scratch length. At the same time, the graphs of the dependences of the penetration depth of the indenter tool, normal and tangential forces on the tangential displacement of the indenter tool were displayed on the monitor screen, and the calculated dependence of the activation energy of plastic deformation on the tangential displacement of the indenter tool was also displayed. After reaching the specified scratch length, the engine of normal loading of the tool-indenter returns to its original state, unloading the tool-indenter, and the motor for moving the carriage returns the carriage to its original state. In the corresponding window, the average value of the activation energy of plastic deformation was highlighted. The obtained value of the activation energy of plastic deformation (u _m = 70 kJ / mol) was stored in computer memory. They clicked on the “Main Menu” button and went to the main window of the work program.

Example No. 6 of the implementation of the private algorithm "D".

The tribometry mode is on. A tool was installed in the holder - a spherical steel tip (⌀ 3 mm). Lubricated the surface of the washer with Tsiatim-201 grease. The value of the tip movement amplitude A = 1.5 mm, the number of double strokes N = 1000, the normal load F _N = 0.5 H, and the maximum linear wear W _h = 10 μm were introduced. Move the table with the sample 1 mm to the right relative to the indenter. Clicked on the "Start" button. Then, the engine of normal loading automatically turned on until the specified value of the normal load acting through the tip on the test surface appears.

The device automatically moved the spherical tip to 20 μm to the left and reset the readings of the vertical displacement sensor. Then, the carriage displacement motor automatically switched on in the reciprocating motion mode with a given amplitude. At the same time, diagrams of readings of sensors of normal and tangential forces, as well as vertical displacements (linear wear) began to be built on the computer screen. After reaching the set value of the number of double strokes, the normal loading motor unloaded the indenter. The achieved linear wear was W _h = 6.5 μm, the amplitude of the friction force was 0.11 N. Saved the received data in computer memory. They clicked on the “Main Menu” button and went to the main window of the work program.

Example No. 7 of the implementation of the private algorithm "E".

Enabled resource prediction mode. They abandoned the resource prediction mode according to the kinetics of changes in the activation energy of plastic deformation. In the input window of the current value of the activation energy of plastic deformation, the last measured value of the activation energy of plastic deformation, u _m = 70 kJ / mol, entered there by default, was left unchanged. Clicked on the "Start" button. The program automatically calculated the predicted residual resource of the material of the surface layer of the investigated washer, which was δ = 87%. Saved the received data in computer memory. They clicked on the “Main Menu” button and went to the main window of the work program.

The tests carried out confirmed the achievement of the assigned technical tasks in the claimed method and device.

The economic efficiency of the proposed method and device is manifested in two directions: a sharp decrease in material costs due to the elimination of the need to use several different devices and devices; the possibility of obtaining qualitatively new results with an investment of time that is several times smaller compared to the application of known methods, that is, with a sharp increase in the productivity of the process of testing samples. Graphic materials of the application contain:

Figure 1 - diagram of the contacting tool indenter with the surface of the sample to assess microhardness;

Figure 2 - scheme of contacting the tool indenter with the surface of the sample to assess the activation energy of plastic deformation;

Figure 3 - diagram of the contacting of the tool indenter with the surface of the sample to assess the tribological properties of the material of the surface layer of the sample;

4 is a diagram of the contacting of the tool with the surface of the sample to assess the roughness;

5 is a diagram of the contacting of the tool with the surface of the sample to assess the waviness;

6 is a functional diagram of the measuring and Executive systems of the device;

7 is a front view of the device;

Fig - section aa device;

Fig.9 is a section bB of the device;

Figure 10 is a longitudinal vertical section through the mechanisms of rotation of the sample in a vertical plane, the mechanism of tangential movement of the sample;

11 - mechanisms for installing and moving the tool;

12 is a flowchart of an implementation of operations of a method for determining the strength characteristics of a material (general algorithm);

Fig - the same, a private algorithm "A";

Fig - the same, a private algorithm "B";

Fig - the same, a private algorithm "B";

Fig - the same, a private algorithm "G";

Fig - the same, a private algorithm "D";

Fig - the same, a private algorithm "E";

Fig - the same, a private algorithm "G".

Used Books

1. RF patent №2166745. The method of evaluating the activation energy of the destruction of the material of the surface layer deformed by friction / D.G. Gromakovsky, E.V. Belenkikh, I.D. Ibatullin et al. Publ. 05/10/2001.

2. RF patent No. 2080581. A method for determining the strength characteristics of metals and their alloys / A.E. Kubarev, L.Kh. Annaberdiev. Publ. 05/27/1997, bull. No. 15.

3. RF patent No. 2277232. A method for determining the strength characteristics of a material and a device for its implementation / M.B. Bakirov, S.Yu. Ganigin, D.G. Gromakovsky, V.V. Dikop, A.V. Dynnikov, I.D. Ibatullin et al. Publ. 05/27/2006, bull. No. 15.

4. RF patent No. 2093814. Device for monitoring the technical condition of the rim of a railway wheel / Bernard Kato, Valerio Del Fabro, Guy Steveno, Publ. 10/20/1997, bull. No. 29.

5. RF patent No. 2067753. A device for determining the hardness of the studs of steam turbines / I.A. Permitin, G.A. Bologov, A.A. Aznabaev, V.A. Agafonov. Publ. 10/10/1996, bull. No. 28.

6. Matyunin V.M. Methods and means of an exemplary rapid assessment of the mechanical properties of structural materials. Textbook for the course "Diagnostics of the structural-mechanical state of metal" / Ed. V.G. Borisov. - M.: Publishing House MPEI. 2001 .-- 94 p. S.77-78, Fig. 7.12.

Claims (8)

1. The method of determining the strength characteristics of the material, in which the test is carried out on the surface of the samples, characterized in that they use a program to select the type of study and conduct it from several possible automatically implemented on the same device, as profiling - profiling of the roughness of the sample; microhardness assessment of a sample surface; assessment of the activation energy of plastic deformation; tribometry; prediction of residual life (at the current value or kinetics of changes in the activation energy of plastic deformation); profiling - profilometry waviness of the surface of the sample; include a personal computer information processing unit, download a work program for selecting a type of study and its conduct; turn the knob of fixing the tool to the "measurement" position, moving the suspension away with the cam; fat-free and dried sample is placed on the table with the studied surface perpendicular to the axis of movement of the tool; install the appropriate tool in the holder; enter the required initial data and study modes into the work program for selecting the type of study and its conduct; press the "start" button of the window of the work program for selecting the type of study and its conduct; lower the traverse with the tool head until the tool touches the test surface of the sample, determining its moment of contact according to the readings of the sensor of vertical movements of the tool; the engine for horizontal movement of the carriage moves the carriage to the distance of the exit of the top of the tool from the deformed region of the investigated surface to zero readings of the sensor of vertical movements of the tool; implement the algorithm for further actions according to the result of the choice of research types. 2. The method according to claim 1, characterized in that after selecting the type of research - the assessment of the microhardness of the surface of the sample enter the required number of measurements, the value of the normal load; install the tool - a standard Vickers diamond indenter (a tetrahedral pyramid with an angle at the apex of 136 °); include a loading engine; press on the free end of the flat spring of the suspension load sensor; at the same time, they plot the dependence “normal load F _N [H] - the value of the penetration of the tool-indenter h [μm] into the test surface” (h = f (F _N )); simultaneously calculate the microhardness value by the formula $${\text{H}}_{\text{μ}}=\frac{\text{1854}\text{,four}\cdot \text{m}}{{\text{D}}^{\text{2}}}$$

, [kgf / mm ² ], where D = h / 0.14 [μm] is the diagonal size of the print, m = F _N · 10 ^-3 · g ^-1 ≈F _N · 10 ^-2 , [g] is the equivalent mass hinges; plotting the dependence Hµ = f (h); save the results of the calculations in the memory of the information processing unit. 3. The method according to claim 1, characterized in that after selecting the type of research - profiling - profiling of the surface roughness of the sample when choosing the desired research mode, set the base length of the surface scan path; set the tool - a diamond needle with an angle at the apex of 60 ° in the holder; automatically turn on the engine of horizontal movement of the carriage; move the tool - a diamond needle along the surface under investigation in the scanning mode (without applying a normal load) by the value of the base length; at the same time, a graph of the dependence “vertical movement of the tool — diamond needle — horizontal movement of the test sample” in real time is plotted; when setting several numbers of specified measurements, the action is repeated a specified number of times; display the middle line of the profile, the lines of the depressions and protrusions, the curve of the supporting surface; parameters R2 are calculated and displayed on the screen of the monitor — roughness height, Ra — arithmetic mean deviation, tm — step; the found values of the roughness profile criteria of the studied surface of the sample are stored in the memory of the information processing unit; return the carriage to its original position; turn the knob for fixing the tool - the diamond needle to the "storage" position, while raising the suspension; save the results of the calculations in the memory of the information processing unit. 4. The method according to claim 1, characterized in that after selecting the type of research - evaluation of the activation energy of plastic deformation, select the required measurement criterion - for a given value of the normal load or the introduction of an indenter tool; depending on the choice of the required measurement criterion, the value of the normal load or the penetration depth of the indenter tool when scratching is entered, the value of the molar volume of the material of the test sample, the number of measurements, the required length of the scratch; set the tool - a tetrahedral pyramid with an angle at the apex of 136 ° into the holder; turn on the engine of normal loading; load the suspension normal to a predetermined value of the normal load or to a predetermined amount of penetration of the indenter tool into the surface of the test sample, depending on the choice of the required measurement criterion; turn on the engine for horizontal movement of the carriage; scratch the surface of the test sample by the indenter tool by a predetermined amount; simultaneously measure the force of scratching; calculate the activation energy of plastic deformation; return the carriage to its original position; save the current value of the activation energy of plastic deformation in the memory of the information processing unit. 5. The method according to claim 1, characterized in that after selecting the type of research - forecasting the residual life, the initial value of the activation energy of plastic deformation of the surface layer and the value of the activation energy of the destruction of the material of the surface layer are set; choose the type of prediction (according to the current value of the activation energy of plastic deformation or the kinetics of changes in the activation energy of plastic deformation); when predicting the current value of the activation energy of plastic deformation, determine the expected time of fracture t _pec and the residual life of the material δ by the formulas:
$${\text{t}}_{\text{pec}}=\frac{\text{one hundred}}{\text{one hundred}-\text{δ}}{\text{t}}_{\text{exp}},$$

$$\text{δ}=\text{one hundred}\cdot \text{(one}-\frac{{\text{U}}_{\text{0}}-{\text{U}}_{\text{0}}^{\text{out}}}{{\text{U}}_{\text{0}}^{\text{cr}}-{\text{U}}_{\text{0}}^{\text{out}}}\text{)}\text{,}$$

where t _exp - the duration of the time the material in units of time; U ₀ $${\text{U}}_{\text{0}}^{\text{out}}$$

, $${\text{U}}_{\text{0}}^{\text{cr}}$$

- current, initial, critical (maximum permissible) value of the activation energy of plastic deformation of the material, respectively; when predicting the kinetics of changes in the activation energy of plastic deformation, a table of initial data is constructed containing the previously found values of the activation energy of plastic deformation of the material under study and the corresponding operating time values; choose the type of approximation (linear or non-linear); using a work program, a dependency is automatically built on the computer screen in the coordinates "running hours - activation energy of plastic deformation" approximated by the least squares method and horizontal lines corresponding to the initial and critical levels of activation energy of plastic deformation of the material; automatically determine the intersection point of the approximated dependence with a critical value of activation energy; the axis value at the intersection point is taken as the predicted value of the material production time corresponding to its destruction, the predicted value of the material production time is stored in the memory of the information processing unit. 6. The method according to claim 1, characterized in that after selecting the type of research - tribometrics specify the magnitude of the normal load, speed, amplitude and time of movement of the carriage; set the tool - a spherical indenter in the holder; applying a layer of lubricant to the surface of the test sample; automatically turn on the loading engine; press on the tool - a spherical indenter with a normal force to a predetermined value with fixing by the load sensor of the suspension with a normal force; turn on the longitudinal motion engine in the reciprocating motion mode with a given speed, amplitude and test time; measure the friction force according to the readings of the tangential force sensor, the normal force acting on the tool-indenter, the displacement of the tool-indenter relative to the surface of the test sample, the linear wear on the difference of the readings of the sensor of vertical displacements of the tool-indenter; return the tool-indenter and the carriage to its original position; save the result of the calculations in the memory of the information processing unit. 7. The method according to claim 1, characterized in that after selecting the type of research - profiling - profilometry of the undulation of the surface of the sample when choosing the desired research mode, set the length of the scan path of the surface of the sample; set the tool - a diamond needle with an angle at the apex of 60 ° in the holder; automatically turn on the engine for horizontal movement of the table along with the sample by the length of the scan path (without applying a normal load); simultaneously with the movement of the sample, a graph is plotted on the computer screen of the dependence "vertical movement of the tool - horizontal movement of the test sample" in real time; when setting several numbers of specified measurements, the action is repeated a specified number of times; display the middle line of the profile, the line of depressions and protrusions; calculate the parameters W _z - height of undulation S _w - step of undulation; the found values of the criteria for the undulation profile of the investigated surface of the sample are stored in the memory of the information processing unit; return the carriage and the tool - the diamond needle to its original position; turn the knob for fixing the tool - the diamond needle to the "storage" position, while raising the suspension; save the results of the calculations in the memory of the information processing unit. 8. A device for determining the strength characteristics of a material according to claim 1, comprising a box-shaped hollow body with an electric motor and a gearbox inside it; two parallel columns mounted on the casing with installed on them with the possibility of moving a traverse along them together with mechanisms for fixing it on the columns and a tool fixed on it; a tool head, a tool mounting mechanism, a mechanism for bringing the tool in and out of the sample surface, a measuring instrument for normal tool movements, a normal force sensor, a mechanism and a table for installing and thermally stabilizing the sample; mechanism of normal tool loading; an automated system for setting a program for loading and unloading, reading, writing and processing information from test results together with a personal computer, characterized in that it is additionally equipped with a mechanism for tangential movement of the sample; the mechanism of rotation of the sample in a vertical plane; the mechanism of thin movement of the sample in a vertical plane; a mechanism for accelerated movement and fixation of the tool; tangential force sensor; the mechanism of vertical movement of the traverse; while the mechanism and the table for installing and thermal stabilization of the sample is made in the form of a table and a plate mounted on the device’s body, interconnected by a tangential movement mechanism of the sample, made, in turn, in the form of a lower case connected to the plate with the possibility of moving along its longitudinal guide by means of a stepper motor located in the lower case and a rack and pinion gear, the rack gear of which is fixed to the rotor of the stepper motor, and the rack is mounted on a plate, and the mechanism the sample is rotated in a vertical plane, fastened by a table made in the form of an upper wedge and a lower wedge mounted on the upper case with the possibility of moving along its guides by rotation of the spindle handle fixed in the bearing of the upper case and connected with the threaded hole of the lower wedge; moreover, the upper wedge is connected by means of a flat and twisted springs to the lower body with the possibility of rotation relative to it by means of a sample rotation mechanism in a vertical plane, consisting of a flywheel - a screw handle that can rotate in a nut fixed to the lower body and rest against the heel with a spherical end, fixed in the upper case; and the mechanism of vertical movement of the traverse is made in the form of a stepper motor, a reducer, including a belt drive, an intermediate shaft with two worms at its ends and two worm gears on two lead screws, passed inside the corresponding two columns and inside the case, two lead nuts mounted on two cradles rigidly fixed to the traverse, mounted on the respective columns in a movable landing with the possibility of fixing on them by means of the traverse fixing mechanisms; the mechanism of accelerated movement and fixation of the tool is made in the form of a disk cam and a handle for its rotation; the mechanism of normal tool loading and the mechanism of tangential movement of the tool are made in the form of a carriage suspended on pairwise plane-parallel springs with the possibility of movement, in two mutually perpendicular directions, by means of the respective two perpendicularly mounted linear step motors.

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