Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail
Although several studies have been conducted on the mechanism of the formation of white layer by cyclic large shear deformation, and its effect on rolling contact fatigue, limited research has been carried out to find a correlation between sub-superficial layer of running contact surface and the cry...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2019-11-01
|
| Series: | Journal of Materials Research and Technology |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2238785419308270 |
| _version_ | 1818309695830491136 |
|---|---|
| author | Mohammad Masoumi Nelson Batista de Lima Gustavo Tressia Amilton Sinatora Hélio Goldenstein |
| author_facet | Mohammad Masoumi Nelson Batista de Lima Gustavo Tressia Amilton Sinatora Hélio Goldenstein |
| author_sort | Mohammad Masoumi |
| collection | DOAJ |
| description | Although several studies have been conducted on the mechanism of the formation of white layer by cyclic large shear deformation, and its effect on rolling contact fatigue, limited research has been carried out to find a correlation between sub-superficial layer of running contact surface and the crystallographic orientation, microstructural changes, and distribution of shear deformation and dislocation density. In order to understand the microstructural evolution (i.e., microstructure and crystallographic orientation) a used pearlitic rail sample removed from the heavy-haul railroad was investigated in the current work. A very thin superficial white layer was observed, approximately 15 μm below the running contact surface. X-ray diffraction analysis confirmed the formation of a supersaturated ferrite phase with carbon content of approximately 3.78 C wt%. It could be attributed to the cementite dissolution due to severe shear and compressive stresses, during intense shear plastic deformation, from the rail-wheel interaction. The dominance of {110} ferrite grains parallel to the rail direction was characterised, in the transition layer between white layer and non-deformed pearlite structure, by X-ray diffraction and electron backscattered diffraction techniques. Formation of these grains, corresponding to the closed-pack plane of the ferrite matrix at the transition region, leads to great ductility and retarded crack formation. Keywords: Severe plastic deformation, White layer, Crystallographic texture, EBSD |
| first_indexed | 2024-12-13T07:34:16Z |
| format | Article |
| id | doaj.art-b45e8246595a4f37809874f3476fcef4 |
| institution | Directory Open Access Journal |
| issn | 2238-7854 |
| language | English |
| last_indexed | 2024-12-13T07:34:16Z |
| publishDate | 2019-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Materials Research and Technology |
| spelling | doaj.art-b45e8246595a4f37809874f3476fcef42022-12-21T23:55:08ZengElsevierJournal of Materials Research and Technology2238-78542019-11-018662756288Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic railMohammad Masoumi0Nelson Batista de Lima1Gustavo Tressia2Amilton Sinatora3Hélio Goldenstein4Universidade Federal do ABC, Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas, Santo André, SP 09210-580 Brazil; Corresponding author.Instituto de Pesquisas Energéticas e Nucleares-IPEN, São Paulo, SP, 05508-900 BrazilInstituto Tecnológico Vale, Av. Juscelino Kubitschek 31, Bauxita, Ouro Preto, MG 35400-000, BrazilInstituto Tecnológico Vale, Av. Juscelino Kubitschek 31, Bauxita, Ouro Preto, MG 35400-000, BrazilEscola Politécnica da Universidade de São Paulo, Departamento de Engenharia Metalúrgica e de Materiais, São Paulo, SP, 05508-030, BrazilAlthough several studies have been conducted on the mechanism of the formation of white layer by cyclic large shear deformation, and its effect on rolling contact fatigue, limited research has been carried out to find a correlation between sub-superficial layer of running contact surface and the crystallographic orientation, microstructural changes, and distribution of shear deformation and dislocation density. In order to understand the microstructural evolution (i.e., microstructure and crystallographic orientation) a used pearlitic rail sample removed from the heavy-haul railroad was investigated in the current work. A very thin superficial white layer was observed, approximately 15 μm below the running contact surface. X-ray diffraction analysis confirmed the formation of a supersaturated ferrite phase with carbon content of approximately 3.78 C wt%. It could be attributed to the cementite dissolution due to severe shear and compressive stresses, during intense shear plastic deformation, from the rail-wheel interaction. The dominance of {110} ferrite grains parallel to the rail direction was characterised, in the transition layer between white layer and non-deformed pearlite structure, by X-ray diffraction and electron backscattered diffraction techniques. Formation of these grains, corresponding to the closed-pack plane of the ferrite matrix at the transition region, leads to great ductility and retarded crack formation. Keywords: Severe plastic deformation, White layer, Crystallographic texture, EBSDhttp://www.sciencedirect.com/science/article/pii/S2238785419308270 |
| spellingShingle | Mohammad Masoumi Nelson Batista de Lima Gustavo Tressia Amilton Sinatora Hélio Goldenstein Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail Journal of Materials Research and Technology |
| title | Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail |
| title_full | Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail |
| title_fullStr | Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail |
| title_full_unstemmed | Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail |
| title_short | Microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail |
| title_sort | microstructure and crystallographic orientation evolutions below the superficial white layer of a used pearlitic rail |
| url | http://www.sciencedirect.com/science/article/pii/S2238785419308270 |
| work_keys_str_mv | AT mohammadmasoumi microstructureandcrystallographicorientationevolutionsbelowthesuperficialwhitelayerofausedpearliticrail AT nelsonbatistadelima microstructureandcrystallographicorientationevolutionsbelowthesuperficialwhitelayerofausedpearliticrail AT gustavotressia microstructureandcrystallographicorientationevolutionsbelowthesuperficialwhitelayerofausedpearliticrail AT amiltonsinatora microstructureandcrystallographicorientationevolutionsbelowthesuperficialwhitelayerofausedpearliticrail AT heliogoldenstein microstructureandcrystallographicorientationevolutionsbelowthesuperficialwhitelayerofausedpearliticrail |