| Autor: |
Yasamin Khebreh Farshchi, Farzad Khodabakhshi, Maryam Mohri, Hassan Shirazi, Mahmoud Nili-Ahmadabadi |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Journal of Materials Research and Technology, Vol 28, Iss , Pp 490-499 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2238-7854 |
| DOI: |
10.1016/j.jmrt.2023.11.280 |
| Popis: |
The main object of the present study is focused on the systematic processing heat-input design based on directed energy deposition (DED) methodology, enrolling carbon steel phase transformation to control the mechanical properties. Three different 4-layer low-carbon alloy steel (ER70S-6) walls are fabricated to investigate this matter with varying heat-inputs. To justify heat-inputs, single layers by metal-inert gas (MIG) welding with different heat-inputs were carried out, and the results were used as input data to the 4-layers fabrication. In addition, to get a more homogenous structure, some walls' heat-inputs have descended from the first layer to the top layer. The microstructural studies show that reducing heat-input causes a higher solidification rate and the formation of finer columnar grains, which significantly affects the mechanical properties. Electron microscopy analysis reveals that a higher cooling rate in the wall with descending heat-input from bottom to top (496 J/mm to 382 J/mm), motivates formation of the acicular ferrite and bainite, which significantly enhances the mechanical properties. The exceptional tensile toughness of the wall, ∼28.86 GPa%, with an ultimate tensile strength (UTS) of ∼740 MPa, yield stress of ∼560 MPa, and an elongation to failure of ∼38 % depicted the impact of fine and multi-constituents' microstructure by heat-input control. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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