Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded Preform
Using a preform fabricated by a cold forward extrusion process, the present study numerically predicted and experimentally investigated its residual stress and microstructural characteristics, as well as its plastic deformation damage and hardness. Prior to realizing the preform, AISI 1035 cold-draw...
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| Language: | English |
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MDPI AG
2023-03-01
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| Online Access: | https://www.mdpi.com/1996-1944/16/6/2448 |
| _version_ | 1797610445397295104 |
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| author | Tae-Wan Ku |
| author_facet | Tae-Wan Ku |
| author_sort | Tae-Wan Ku |
| collection | DOAJ |
| description | Using a preform fabricated by a cold forward extrusion process, the present study numerically predicted and experimentally investigated its residual stress and microstructural characteristics, as well as its plastic deformation damage and hardness. Prior to realizing the preform, AISI 1035 cold-drawn medium carbon steel material with a diameter of 50.0 mm and a height of 121.0 mm is first spheroidized and annealed, after which phosphophyllite is used to coat its outer surface. To identify the influence of the spheroidizing and annealing on the mechanical properties and the microstructural phase, uniaxial compression tests and microscopic observations are carried out. After assuming the deformation behavior of the workpiece during the cold forward extrusion with a plastic material model and with an elasto-plastic material model, separately, three-dimensional finite element simulations are adopted to visualize the residual stress and the plastic deformation damage. The preform produced by cold forward extrusion is fully scanned by using an optical 3D scanner, the Vickers micro-hardness is measured, and the residual stress through EBSD (electron backscatter diffraction) analysis is observed. Briefly, the results show that the ferrite and pearlite within the raw workpiece is well spheroidized by the heat treatment, and that there is a decrease in the KAM (kernel average misorientation) value of about 40%. In terms of the preform obtained by the cold forward extrusion, the dimensional requirement is more suitably met with the predicted layout when adopting the elasto-plastic material model than that of the plastic material one, and the numerically predicted residual stress agrees with the Vickers micro-hardness distribution. It can be verified that the dislocation density (or the internally stored strain energy) based on the IQ map and the IPF map is substantially increased around the extrusion region, and that the KAM value is increased by roughly 516% as the whole average of the observed values. |
| first_indexed | 2024-03-11T06:14:43Z |
| format | Article |
| id | doaj.art-7ae9aa0a0e92499bb9714a634ee75e52 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-11T06:14:43Z |
| publishDate | 2023-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-7ae9aa0a0e92499bb9714a634ee75e522023-11-17T12:22:26ZengMDPI AGMaterials1996-19442023-03-01166244810.3390/ma16062448Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded PreformTae-Wan Ku0Engineering Research Center of Innovative Technology on Advanced Forming, Pusan National University, Geumjeong-gu, Busan 46241, Republic of KoreaUsing a preform fabricated by a cold forward extrusion process, the present study numerically predicted and experimentally investigated its residual stress and microstructural characteristics, as well as its plastic deformation damage and hardness. Prior to realizing the preform, AISI 1035 cold-drawn medium carbon steel material with a diameter of 50.0 mm and a height of 121.0 mm is first spheroidized and annealed, after which phosphophyllite is used to coat its outer surface. To identify the influence of the spheroidizing and annealing on the mechanical properties and the microstructural phase, uniaxial compression tests and microscopic observations are carried out. After assuming the deformation behavior of the workpiece during the cold forward extrusion with a plastic material model and with an elasto-plastic material model, separately, three-dimensional finite element simulations are adopted to visualize the residual stress and the plastic deformation damage. The preform produced by cold forward extrusion is fully scanned by using an optical 3D scanner, the Vickers micro-hardness is measured, and the residual stress through EBSD (electron backscatter diffraction) analysis is observed. Briefly, the results show that the ferrite and pearlite within the raw workpiece is well spheroidized by the heat treatment, and that there is a decrease in the KAM (kernel average misorientation) value of about 40%. In terms of the preform obtained by the cold forward extrusion, the dimensional requirement is more suitably met with the predicted layout when adopting the elasto-plastic material model than that of the plastic material one, and the numerically predicted residual stress agrees with the Vickers micro-hardness distribution. It can be verified that the dislocation density (or the internally stored strain energy) based on the IQ map and the IPF map is substantially increased around the extrusion region, and that the KAM value is increased by roughly 516% as the whole average of the observed values.https://www.mdpi.com/1996-1944/16/6/2448residual stressplastic deformation damagehardnessmicrostructurefinite element simulationcold forward extrusion |
| spellingShingle | Tae-Wan Ku Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded Preform Materials residual stress plastic deformation damage hardness microstructure finite element simulation cold forward extrusion |
| title | Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded Preform |
| title_full | Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded Preform |
| title_fullStr | Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded Preform |
| title_full_unstemmed | Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded Preform |
| title_short | Numerical and Experimental Investigations on Residual Stress and Hardness within a Cold Forward Extruded Preform |
| title_sort | numerical and experimental investigations on residual stress and hardness within a cold forward extruded preform |
| topic | residual stress plastic deformation damage hardness microstructure finite element simulation cold forward extrusion |
| url | https://www.mdpi.com/1996-1944/16/6/2448 |
| work_keys_str_mv | AT taewanku numericalandexperimentalinvestigationsonresidualstressandhardnesswithinacoldforwardextrudedpreform |