Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps
A non contact technique is presented, that provides information on thermal properties at the cubic micron scale in metal surfaces. It makes use of the appearance of bumps originated in the thermoelastic deformation of the surface induced by laser heating with a modulated beam. The heat diffusion and...
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2006
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_39013841_v_n_p490_Martinez http://hdl.handle.net/20.500.12110/paper_39013841_v_n_p490_Martinez |
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paper:paper_39013841_v_n_p490_Martinez2023-06-08T16:36:50Z Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps Martínez, Oscar Eduardo Mingolo, Nélida Alloys Deformation Heat treating furnaces Heat treatment Laser heating Lasers Liquid metals Metallic compounds Metallic glass Metals Modulation Quenching Surface analysis Surface diffusion Surface treatment Technology Thermal expansion Thermal spraying Thermodynamic properties Thermoelasticity Analytical modelling Beam diameters Critical frequencies Heat diffusions International Federation for Heat Treatment Knife edge Laser modulation Local heating Metal surfaces Metallic glasses Metallic surfaces Micron-scale Microscopic characterization Modulation period Non-contact Photo-induced Reflected signals Surface deformations Surface engineering Thermal properties Surface properties A non contact technique is presented, that provides information on thermal properties at the cubic micron scale in metal surfaces. It makes use of the appearance of bumps originated in the thermoelastic deformation of the surface induced by laser heating with a modulated beam. The heat diffusion and thermal expansion give rise to a surface deformation shaping a modulated bump at the laser modulation frequency. A second beam is reflected at the bump and the collected amplitude depends both on the change in reflectivity with temperature (thermoreflectance) and the deflection of the beam due to the surface deformation (photodeflection). Filtering the reflected signal with an adjusTable knife edge the photodeflection signal can be enhanced. A complete analytical model is presented that takes into account both mechanisms. A critical modulating frequency appears at which the heat diffuses the entire laser beam diameter in one modulation period. From the determination of that critical frequency the local heat diffusivity can be determined. Experimental results are presented on poor conducting metallic glasses, confirming the theoretical predictions. Fil:Martínez, O.E. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Mingolo, N. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2006 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_39013841_v_n_p490_Martinez http://hdl.handle.net/20.500.12110/paper_39013841_v_n_p490_Martinez |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Alloys Deformation Heat treating furnaces Heat treatment Laser heating Lasers Liquid metals Metallic compounds Metallic glass Metals Modulation Quenching Surface analysis Surface diffusion Surface treatment Technology Thermal expansion Thermal spraying Thermodynamic properties Thermoelasticity Analytical modelling Beam diameters Critical frequencies Heat diffusions International Federation for Heat Treatment Knife edge Laser modulation Local heating Metal surfaces Metallic glasses Metallic surfaces Micron-scale Microscopic characterization Modulation period Non-contact Photo-induced Reflected signals Surface deformations Surface engineering Thermal properties Surface properties |
| spellingShingle |
Alloys Deformation Heat treating furnaces Heat treatment Laser heating Lasers Liquid metals Metallic compounds Metallic glass Metals Modulation Quenching Surface analysis Surface diffusion Surface treatment Technology Thermal expansion Thermal spraying Thermodynamic properties Thermoelasticity Analytical modelling Beam diameters Critical frequencies Heat diffusions International Federation for Heat Treatment Knife edge Laser modulation Local heating Metal surfaces Metallic glasses Metallic surfaces Micron-scale Microscopic characterization Modulation period Non-contact Photo-induced Reflected signals Surface deformations Surface engineering Thermal properties Surface properties Martínez, Oscar Eduardo Mingolo, Nélida Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps |
| topic_facet |
Alloys Deformation Heat treating furnaces Heat treatment Laser heating Lasers Liquid metals Metallic compounds Metallic glass Metals Modulation Quenching Surface analysis Surface diffusion Surface treatment Technology Thermal expansion Thermal spraying Thermodynamic properties Thermoelasticity Analytical modelling Beam diameters Critical frequencies Heat diffusions International Federation for Heat Treatment Knife edge Laser modulation Local heating Metal surfaces Metallic glasses Metallic surfaces Micron-scale Microscopic characterization Modulation period Non-contact Photo-induced Reflected signals Surface deformations Surface engineering Thermal properties Surface properties |
| description |
A non contact technique is presented, that provides information on thermal properties at the cubic micron scale in metal surfaces. It makes use of the appearance of bumps originated in the thermoelastic deformation of the surface induced by laser heating with a modulated beam. The heat diffusion and thermal expansion give rise to a surface deformation shaping a modulated bump at the laser modulation frequency. A second beam is reflected at the bump and the collected amplitude depends both on the change in reflectivity with temperature (thermoreflectance) and the deflection of the beam due to the surface deformation (photodeflection). Filtering the reflected signal with an adjusTable knife edge the photodeflection signal can be enhanced. A complete analytical model is presented that takes into account both mechanisms. A critical modulating frequency appears at which the heat diffuses the entire laser beam diameter in one modulation period. From the determination of that critical frequency the local heat diffusivity can be determined. Experimental results are presented on poor conducting metallic glasses, confirming the theoretical predictions. |
| author |
Martínez, Oscar Eduardo Mingolo, Nélida |
| author_facet |
Martínez, Oscar Eduardo Mingolo, Nélida |
| author_sort |
Martínez, Oscar Eduardo |
| title |
Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps |
| title_short |
Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps |
| title_full |
Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps |
| title_fullStr |
Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps |
| title_full_unstemmed |
Microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps |
| title_sort |
microscopic characterization of metallic surfaces by photoinduced thermoelastic bumps |
| publishDate |
2006 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_39013841_v_n_p490_Martinez http://hdl.handle.net/20.500.12110/paper_39013841_v_n_p490_Martinez |
| work_keys_str_mv |
AT martinezoscareduardo microscopiccharacterizationofmetallicsurfacesbyphotoinducedthermoelasticbumps AT mingolonelida microscopiccharacterizationofmetallicsurfacesbyphotoinducedthermoelasticbumps |
| _version_ |
1768546467521232896 |