Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process
The interactive effect of grain size and specimen dimensions on the material flow and microstructural evolution was studied in a progressive open-die microforming process. Particular interest was paid on the effect of the number of grains over the initial specimen thickness, on the evolution of the...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Journal Article |
| Language: | English |
| Published: |
2016
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| Online Access: | https://hdl.handle.net/10356/85028 http://hdl.handle.net/10220/39614 |
| _version_ | 1811684259805528064 |
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| author | Ghassemali, Ehsan Tan, Ming-Jen Wah, Chua Beng Jarfors, Anders E.W. Lim, S.C.V. |
| author2 | School of Mechanical and Aerospace Engineering |
| author_facet | School of Mechanical and Aerospace Engineering Ghassemali, Ehsan Tan, Ming-Jen Wah, Chua Beng Jarfors, Anders E.W. Lim, S.C.V. |
| author_sort | Ghassemali, Ehsan |
| collection | NTU |
| description | The interactive effect of grain size and specimen dimensions on the material flow and microstructural evolution was studied in a progressive open-die microforming process. Particular interest was paid on the effect of the number of grains over the initial specimen thickness, on the evolution of the dead metal zone (DMZ) in the final micro-component's microstructure. Such a DMZ is deemed unfavorable for mechanical properties of the pin. Interestingly, experimental results revealed that the DMZ can be removed at the pin surface by increasing the initial grain size. This behavior was attributed to the role of the strain gradient on the deformation. In the aspects of the forming load and dimensional measurements of the final parts, there were no significant size-effects observed in this process. This is because the neutral plane, which demarcates the two directions of material flow in the open-die forging/extrusion process, determines the amount of material flow towards the die orifice, regardless of the initial grain size. |
| first_indexed | 2024-10-01T04:25:47Z |
| format | Journal Article |
| id | ntu-10356/85028 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2024-10-01T04:25:47Z |
| publishDate | 2016 |
| record_format | dspace |
| spelling | ntu-10356/850282020-09-26T22:10:26Z Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process Ghassemali, Ehsan Tan, Ming-Jen Wah, Chua Beng Jarfors, Anders E.W. Lim, S.C.V. School of Mechanical and Aerospace Engineering A*STAR SIMTech Subgrain Size effect Dislocation cells Microforming Dead metal zone The interactive effect of grain size and specimen dimensions on the material flow and microstructural evolution was studied in a progressive open-die microforming process. Particular interest was paid on the effect of the number of grains over the initial specimen thickness, on the evolution of the dead metal zone (DMZ) in the final micro-component's microstructure. Such a DMZ is deemed unfavorable for mechanical properties of the pin. Interestingly, experimental results revealed that the DMZ can be removed at the pin surface by increasing the initial grain size. This behavior was attributed to the role of the strain gradient on the deformation. In the aspects of the forming load and dimensional measurements of the final parts, there were no significant size-effects observed in this process. This is because the neutral plane, which demarcates the two directions of material flow in the open-die forging/extrusion process, determines the amount of material flow towards the die orifice, regardless of the initial grain size. ASTAR (Agency for Sci., Tech. and Research, S’pore) Accepted version 2016-01-07T06:43:54Z 2019-12-06T15:55:53Z 2016-01-07T06:43:54Z 2019-12-06T15:55:53Z 2013 Journal Article Ghassemali, E., Tan, M.-J., Wah, C. B., Jarfors, A. E. W., & Lim, S. C. V. (2013). Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process. Materials Science and Engineering: A, 582, 379-388. 0921-5093 https://hdl.handle.net/10356/85028 http://hdl.handle.net/10220/39614 10.1016/j.msea.2013.06.023 en Materials Science and Engineering: A © 2013 Elsevier B.V. This is the author created version of a work that has been peer reviewed and accepted for publication by Materials Science and Engineering: A, Elsevier B.V. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1016/j.msea.2013.06.023]. 30 p. application/pdf |
| spellingShingle | Subgrain Size effect Dislocation cells Microforming Dead metal zone Ghassemali, Ehsan Tan, Ming-Jen Wah, Chua Beng Jarfors, Anders E.W. Lim, S.C.V. Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process |
| title | Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process |
| title_full | Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process |
| title_fullStr | Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process |
| title_full_unstemmed | Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process |
| title_short | Grain size and workpiece dimension effects on material flow in an open-die micro-forging/extrusion process |
| title_sort | grain size and workpiece dimension effects on material flow in an open die micro forging extrusion process |
| topic | Subgrain Size effect Dislocation cells Microforming Dead metal zone |
| url | https://hdl.handle.net/10356/85028 http://hdl.handle.net/10220/39614 |
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