Inverse dependence of heat accumulation on pulse duration in laser surface processing with ultrashort pulses

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F49777513%3A23210%2F23%3A43969043" target="_blank" >RIV/49777513:23210/23:43969043 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/49777513:23640/23:43969043

Výsledek na webu

<a href="https://doi.org/10.1016/j.ijheatmasstransfer.2023.124328" target="_blank" >https://doi.org/10.1016/j.ijheatmasstransfer.2023.124328</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ijheatmasstransfer.2023.124328" target="_blank" >10.1016/j.ijheatmasstransfer.2023.124328</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Inverse dependence of heat accumulation on pulse duration in laser surface processing with ultrashort pulses

Popis výsledku v původním jazyce

Laser pulse duration is one of the important parameters that is able to dramatically change ablation efficiency. Shorter laser pulse duration leads to deeper transport of absorbed energy in subsurface material layers. Ultra-fast and non-equilibrium processes are able to remarkably affect residual energy, which is accumulated in the deeper subsurface layers after ablation. On the other hand, undesirably high heat accumulation leads to material overheating with surface oxidation, appearance of liquid phase and, as a result, low processing quality. In this paper, the influence of laser pulse duration on the heat accumulation value was experimentally evaluated for the first time. Heat accumulation was measured with a highly sensitive fast infrared detector. The results were presented in comparison with surface structure analysis, material ablation rate and optical reflectivity. Unexpected inverse dependence of heat accumulation on laser pulse duration was detected. An optimal laser pulse duration near 1 ps corresponds to the maximum heat accumulation value and also highest ablation efficiency in contrast to longer laser pulses. The same optimal pulse duration value was detected for low frequency (250 kHz) and for high frequency (1 MHz) laser surface processing regimes. The maximum heat accumulation value was expected at the longest laser pulses. The results are discussed from the point of view of the two-temperature model.

Název v anglickém jazyce

Inverse dependence of heat accumulation on pulse duration in laser surface processing with ultrashort pulses

Popis výsledku anglicky

Laser pulse duration is one of the important parameters that is able to dramatically change ablation efficiency. Shorter laser pulse duration leads to deeper transport of absorbed energy in subsurface material layers. Ultra-fast and non-equilibrium processes are able to remarkably affect residual energy, which is accumulated in the deeper subsurface layers after ablation. On the other hand, undesirably high heat accumulation leads to material overheating with surface oxidation, appearance of liquid phase and, as a result, low processing quality. In this paper, the influence of laser pulse duration on the heat accumulation value was experimentally evaluated for the first time. Heat accumulation was measured with a highly sensitive fast infrared detector. The results were presented in comparison with surface structure analysis, material ablation rate and optical reflectivity. Unexpected inverse dependence of heat accumulation on laser pulse duration was detected. An optimal laser pulse duration near 1 ps corresponds to the maximum heat accumulation value and also highest ablation efficiency in contrast to longer laser pulses. The same optimal pulse duration value was detected for low frequency (250 kHz) and for high frequency (1 MHz) laser surface processing regimes. The maximum heat accumulation value was expected at the longest laser pulses. The results are discussed from the point of view of the two-temperature model.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20506 - Coating and films

Projekt

<a href="/cs/project/TH75020001" target="_blank" >TH75020001: Pokročilá příprava podkladového materiálu pro povlaky posuvným a ultrarychlým laserovým texturováním</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2023

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER

ISSN

0017-9310

e-ISSN

1879-2189

Svazek periodika

213

Číslo periodika v rámci svazku

OCT 2023

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

8

Strana od-do

—

Kód UT WoS článku

001010729800001

EID výsledku v databázi Scopus

2-s2.0-85162192326