Wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction
The paper examines the method of conducting tribological studies in the dry mode of friction of nitrided and unhardened structural steels 20 and 45 in order to achieve comparable results of laboratory tests with operational characteristics. Preliminary studies of anodized steels of the same steels i...
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| Format: | Article |
| Language: | English |
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Khmelhitsky National University, Lublin University of Technology
2023-03-01
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| Series: | Проблеми трибології |
| Subjects: | |
| Online Access: | https://tribology.khnu.km.ua/index.php/ProbTrib/article/view/899 |
| _version_ | 1797794831998648320 |
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| author | M.S. Stechyshyn M. Ye. Skyba A.V. Martynyuk D.V. Zdorenko |
| author_facet | M.S. Stechyshyn M. Ye. Skyba A.V. Martynyuk D.V. Zdorenko |
| author_sort | M.S. Stechyshyn |
| collection | DOAJ |
| description | The paper examines the method of conducting tribological studies in the dry mode of friction of nitrided and unhardened structural steels 20 and 45 in order to achieve comparable results of laboratory tests with operational characteristics. Preliminary studies of anodized steels of the same steels indicate that under conditions of extreme friction it is extremely difficult, and in some cases impossible, to use such values of specific pressure on the friction surface, at which it would be realistic to compare the results obtained for different samples made of different brands materials and processed using various technological processes. Since during the tests, constant lubrication of the friction zone was ensured, a layer of lubricant was present on the friction surface up to a certain pressure value, which led to extremely small indicators of linear wear. However, depending on the characteristics of the modified surface, there was a critical value of pressure at which the layer of lubricant was squeezed out of the friction zone, which led to instant adhesion of the surfaces. Thus, the study of wear resistance in the dry mode of friction ensures a significantly higher productivity of experiments.
Unlike experiments with limit friction, dry friction can be used for different steels at the same pressure value, which eliminates the problem of comparability of results and contributes to the objectivity of conclusions regarding the effectiveness of various modification processes.
According to the results of previous experiments, such a compromise pressure value can be 16 MPa.
Another important phenomenon for the analysis of the influence of the modification results on the wear resistance characteristics of the surface is established - the effect of relaxation processes in the near-surface layers, which have already acquired structural transformations under the influence of pressure in the friction zone.
For all steels, there is some slowing down of the intensity of wear after a break with a gradual return to the intensity characteristic of a certain brand of steel. The reason for such a phenomenon can only be the relaxation of stresses and the equalization of the characteristics of the structure in the near-surface layers. At the same time, the result is the strengthening of the surface, which explains the decrease in the intensity of the wear process. over time, as the strengthened layer breaks down, the indicators of the surface condition become equal to those before the break and the intensity of wear is restored. |
| first_indexed | 2024-03-13T03:08:44Z |
| format | Article |
| id | doaj.art-524f5a7d70054efda16a86ab12cefa57 |
| institution | Directory Open Access Journal |
| issn | 2079-1372 |
| language | English |
| last_indexed | 2024-03-13T03:08:44Z |
| publishDate | 2023-03-01 |
| publisher | Khmelhitsky National University, Lublin University of Technology |
| record_format | Article |
| series | Проблеми трибології |
| spelling | doaj.art-524f5a7d70054efda16a86ab12cefa572023-06-26T16:33:04ZengKhmelhitsky National University, Lublin University of TechnologyПроблеми трибології2079-13722023-03-01281/107202410.31891/2079-1372-2023-107-1-20-24805Wear resistance of structural steels nitrided in a cyclically switched discharge with dry frictionM.S. Stechyshyn0M. Ye. Skyba1A.V. Martynyuk2D.V. Zdorenko3Khmelnitskyi National UniversityKhmelnitskyi National UniversityKhmelnitskyi National UniversityKhmelnitskyi National UniversityThe paper examines the method of conducting tribological studies in the dry mode of friction of nitrided and unhardened structural steels 20 and 45 in order to achieve comparable results of laboratory tests with operational characteristics. Preliminary studies of anodized steels of the same steels indicate that under conditions of extreme friction it is extremely difficult, and in some cases impossible, to use such values of specific pressure on the friction surface, at which it would be realistic to compare the results obtained for different samples made of different brands materials and processed using various technological processes. Since during the tests, constant lubrication of the friction zone was ensured, a layer of lubricant was present on the friction surface up to a certain pressure value, which led to extremely small indicators of linear wear. However, depending on the characteristics of the modified surface, there was a critical value of pressure at which the layer of lubricant was squeezed out of the friction zone, which led to instant adhesion of the surfaces. Thus, the study of wear resistance in the dry mode of friction ensures a significantly higher productivity of experiments. Unlike experiments with limit friction, dry friction can be used for different steels at the same pressure value, which eliminates the problem of comparability of results and contributes to the objectivity of conclusions regarding the effectiveness of various modification processes. According to the results of previous experiments, such a compromise pressure value can be 16 MPa. Another important phenomenon for the analysis of the influence of the modification results on the wear resistance characteristics of the surface is established - the effect of relaxation processes in the near-surface layers, which have already acquired structural transformations under the influence of pressure in the friction zone. For all steels, there is some slowing down of the intensity of wear after a break with a gradual return to the intensity characteristic of a certain brand of steel. The reason for such a phenomenon can only be the relaxation of stresses and the equalization of the characteristics of the structure in the near-surface layers. At the same time, the result is the strengthening of the surface, which explains the decrease in the intensity of the wear process. over time, as the strengthened layer breaks down, the indicators of the surface condition become equal to those before the break and the intensity of wear is restored.https://tribology.khnu.km.ua/index.php/ProbTrib/article/view/899nitriding, dry friction, limit friction, wear |
| spellingShingle | M.S. Stechyshyn M. Ye. Skyba A.V. Martynyuk D.V. Zdorenko Wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction Проблеми трибології nitriding, dry friction, limit friction, wear |
| title | Wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction |
| title_full | Wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction |
| title_fullStr | Wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction |
| title_full_unstemmed | Wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction |
| title_short | Wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction |
| title_sort | wear resistance of structural steels nitrided in a cyclically switched discharge with dry friction |
| topic | nitriding, dry friction, limit friction, wear |
| url | https://tribology.khnu.km.ua/index.php/ProbTrib/article/view/899 |
| work_keys_str_mv | AT msstechyshyn wearresistanceofstructuralsteelsnitridedinacyclicallyswitcheddischargewithdryfriction AT myeskyba wearresistanceofstructuralsteelsnitridedinacyclicallyswitcheddischargewithdryfriction AT avmartynyuk wearresistanceofstructuralsteelsnitridedinacyclicallyswitcheddischargewithdryfriction AT dvzdorenko wearresistanceofstructuralsteelsnitridedinacyclicallyswitcheddischargewithdryfriction |