Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under Fatigue
Railway wheels are usually attached to axles by press-fitting; therefore, the mechanical processes taking place during operation can result in failure, with fatal consequences for the axle seats. This manuscript describes the effect of laser hardening on the residual stress state, microstructural pa...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-02-01
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| Series: | Metals |
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| Online Access: | https://www.mdpi.com/2075-4701/14/3/290 |
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| author | Jiří Čapek Karel Trojan Jan Kec Nikolaj Ganev Ivo Černý Tomáš Mužík |
| author_facet | Jiří Čapek Karel Trojan Jan Kec Nikolaj Ganev Ivo Černý Tomáš Mužík |
| author_sort | Jiří Čapek |
| collection | DOAJ |
| description | Railway wheels are usually attached to axles by press-fitting; therefore, the mechanical processes taking place during operation can result in failure, with fatal consequences for the axle seats. This manuscript describes the effect of laser hardening on the residual stress state, microstructural parameters (lattice defects—dislocations, crystallites, microstrains, etc.), and mechanical properties of laser-hardened EA1N steel railway axles under fatigue life conditions. Differences were found between ground, single-track, and multi-track hardened surfaces. Tensile residual stresses, low dislocation densities and hardnesses, and different microstructures (tempered cubic martensite) were found at the overlapped tracks and at the boundary of the heat-affected zone and bulk surface compared with the hardened zone. As a result, the surface treatment of axle seats by laser hardening improved the fatigue failure resistance compared with untreated seats. Optimal properties of the integrity of the axle seat surface were achieved, including fatigue resistance, which seems to be positively influenced mainly by sufficient hardness and the appropriate microstructure. The influence of the other investigated parameters was not evident, and was reduced by the presence of fretting corrosion and press-fitting. |
| first_indexed | 2024-04-24T18:01:55Z |
| format | Article |
| id | doaj.art-b3a7bd4fafc6418a8326de799528f260 |
| institution | Directory Open Access Journal |
| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-04-24T18:01:55Z |
| publishDate | 2024-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Metals |
| spelling | doaj.art-b3a7bd4fafc6418a8326de799528f2602024-03-27T13:54:20ZengMDPI AGMetals2075-47012024-02-0114329010.3390/met14030290Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under FatigueJiří Čapek0Karel Trojan1Jan Kec2Nikolaj Ganev3Ivo Černý4Tomáš Mužík5Department of Solid State Engineering, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Trojanova 13, 120 00 Prague, Czech RepublicDepartment of Solid State Engineering, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Trojanova 13, 120 00 Prague, Czech RepublicStrength Laboratory, SVÚM a.s., Tovární 2053, 250 88 Čelákovice, Czech RepublicDepartment of Solid State Engineering, Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Trojanova 13, 120 00 Prague, Czech RepublicStrength Laboratory, SVÚM a.s., Tovární 2053, 250 88 Čelákovice, Czech RepublicMATEX PM, s.r.o., Libušínská 618/60, 326 00 Pilsen, Czech RepublicRailway wheels are usually attached to axles by press-fitting; therefore, the mechanical processes taking place during operation can result in failure, with fatal consequences for the axle seats. This manuscript describes the effect of laser hardening on the residual stress state, microstructural parameters (lattice defects—dislocations, crystallites, microstrains, etc.), and mechanical properties of laser-hardened EA1N steel railway axles under fatigue life conditions. Differences were found between ground, single-track, and multi-track hardened surfaces. Tensile residual stresses, low dislocation densities and hardnesses, and different microstructures (tempered cubic martensite) were found at the overlapped tracks and at the boundary of the heat-affected zone and bulk surface compared with the hardened zone. As a result, the surface treatment of axle seats by laser hardening improved the fatigue failure resistance compared with untreated seats. Optimal properties of the integrity of the axle seat surface were achieved, including fatigue resistance, which seems to be positively influenced mainly by sufficient hardness and the appropriate microstructure. The influence of the other investigated parameters was not evident, and was reduced by the presence of fretting corrosion and press-fitting.https://www.mdpi.com/2075-4701/14/3/290railway axle seatsEA1N steellaser hardeningX-ray diffractionfatigueresidual stresses |
| spellingShingle | Jiří Čapek Karel Trojan Jan Kec Nikolaj Ganev Ivo Černý Tomáš Mužík Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under Fatigue Metals railway axle seats EA1N steel laser hardening X-ray diffraction fatigue residual stresses |
| title | Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under Fatigue |
| title_full | Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under Fatigue |
| title_fullStr | Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under Fatigue |
| title_full_unstemmed | Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under Fatigue |
| title_short | Residual Stresses and the Microstructure of Modeled Laser-Hardened Railway Axle Seats under Fatigue |
| title_sort | residual stresses and the microstructure of modeled laser hardened railway axle seats under fatigue |
| topic | railway axle seats EA1N steel laser hardening X-ray diffraction fatigue residual stresses |
| url | https://www.mdpi.com/2075-4701/14/3/290 |
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