Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laser
Considerable surface roughness, dimensional deviation, and non-uniform microstructure are a few of the characteristics found on thin or micro-scale features fabricated via laser powder bed fusion (LPBF) that yield inferior and/or inconsistent mechanical properties. Femtosecond laser micromachining c...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2021-11-01
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| Series: | Materials & Design |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S0264127521006006 |
| _version_ | 1818719322862780416 |
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| author | Abhi Ghosh Sanchari Biswas Tiffany Turner Anne-Marie Kietzig Mathieu Brochu |
| author_facet | Abhi Ghosh Sanchari Biswas Tiffany Turner Anne-Marie Kietzig Mathieu Brochu |
| author_sort | Abhi Ghosh |
| collection | DOAJ |
| description | Considerable surface roughness, dimensional deviation, and non-uniform microstructure are a few of the characteristics found on thin or micro-scale features fabricated via laser powder bed fusion (LPBF) that yield inferior and/or inconsistent mechanical properties. Femtosecond laser micromachining can aid in fabricating micro-scale parts with ultra-high dimensional precision. In this work, the surface and tensile behavior of microstruts of 500μm nominal diameter micromachined with Gaussian laser pulses of <100fs duration are characterized. Roughness parameters such as Ra=0.9±0.2μm and Rz=3.4±1.3μm are achieved on the micromachined faces. Surface-associated grains are successfully ablated with negligible microstructural damage to the microstruts. As a result, the average uniform strain under quasi-static tensile loading is measured as 0.54±0.02 compared to 0.42±0.01 for the as-built microstruts. Uniform and non-uniform deformation strain portions are separated analytically and characterized primarily via in-situ imaging. Progressive degradation of the surface and dimensional variance is observed on the micromachined test specimens. Post necking initiation, ablation-associated asperities on the micromachined surfaces evolve into notches, leading to tensile failure. |
| first_indexed | 2024-12-17T20:05:06Z |
| format | Article |
| id | doaj.art-33ed48d2be524abea7bf1f76207d98d8 |
| institution | Directory Open Access Journal |
| issn | 0264-1275 |
| language | English |
| last_indexed | 2024-12-17T20:05:06Z |
| publishDate | 2021-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Materials & Design |
| spelling | doaj.art-33ed48d2be524abea7bf1f76207d98d82022-12-21T21:34:21ZengElsevierMaterials & Design0264-12752021-11-01210110045Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laserAbhi Ghosh0Sanchari Biswas1Tiffany Turner2Anne-Marie Kietzig3Mathieu Brochu4Department of Mining and Materials Engineering, McGill University, Rm 2140, Wong Building, 3610 University St., Montreal, QC H3A 0C5, CanadaDepartment of Chemical Engineering, McGill University, Wong Building, 3610 University St., Montreal, QC H3A 0C5, CanadaDepartment of Mining and Materials Engineering, McGill University, Rm 2140, Wong Building, 3610 University St., Montreal, QC H3A 0C5, CanadaDepartment of Chemical Engineering, McGill University, Wong Building, 3610 University St., Montreal, QC H3A 0C5, CanadaDepartment of Mining and Materials Engineering, McGill University, Rm 2140, Wong Building, 3610 University St., Montreal, QC H3A 0C5, Canada; Corresponding author at: Rm 2140, Wong Building, 3610 University St., Montreal, QC H3A 0C5, Canada.Considerable surface roughness, dimensional deviation, and non-uniform microstructure are a few of the characteristics found on thin or micro-scale features fabricated via laser powder bed fusion (LPBF) that yield inferior and/or inconsistent mechanical properties. Femtosecond laser micromachining can aid in fabricating micro-scale parts with ultra-high dimensional precision. In this work, the surface and tensile behavior of microstruts of 500μm nominal diameter micromachined with Gaussian laser pulses of <100fs duration are characterized. Roughness parameters such as Ra=0.9±0.2μm and Rz=3.4±1.3μm are achieved on the micromachined faces. Surface-associated grains are successfully ablated with negligible microstructural damage to the microstruts. As a result, the average uniform strain under quasi-static tensile loading is measured as 0.54±0.02 compared to 0.42±0.01 for the as-built microstruts. Uniform and non-uniform deformation strain portions are separated analytically and characterized primarily via in-situ imaging. Progressive degradation of the surface and dimensional variance is observed on the micromachined test specimens. Post necking initiation, ablation-associated asperities on the micromachined surfaces evolve into notches, leading to tensile failure.http://www.sciencedirect.com/science/article/pii/S0264127521006006Laser powder bed fusionStainless steel 316LMicrostrutsSurface roughnessFemtosecond laserMicromachining |
| spellingShingle | Abhi Ghosh Sanchari Biswas Tiffany Turner Anne-Marie Kietzig Mathieu Brochu Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laser Materials & Design Laser powder bed fusion Stainless steel 316L Microstruts Surface roughness Femtosecond laser Micromachining |
| title | Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laser |
| title_full | Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laser |
| title_fullStr | Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laser |
| title_full_unstemmed | Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laser |
| title_short | Surface, microstructure, and tensile deformation characterization of LPBF SS316L microstruts micromachined with femtosecond laser |
| title_sort | surface microstructure and tensile deformation characterization of lpbf ss316l microstruts micromachined with femtosecond laser |
| topic | Laser powder bed fusion Stainless steel 316L Microstruts Surface roughness Femtosecond laser Micromachining |
| url | http://www.sciencedirect.com/science/article/pii/S0264127521006006 |
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