The influence of pulse duration on the stress levels in ablation of ceramics: A finite element study

• Autor(a) principal: Vila Verde, A.
• Data de Publicação: 2006
• Outros Autores: Ramos, Marta M. D.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/1822/5062
• topic: Mesoscopic modelling; Laser ablation; Enamel; Finite elements; CO2 laser; Pulse; pulse duration; stress transients; CO laser 2; Science & Technology

We present a finite element model to investigate the dynamic thermal and mechanical response of ceramic materials to pulsed infrared radiation. The model was applied to the specific problem of determining the influence of the pulse duration on the stress levels reached in human dental enamel irradiated by a CO2 laser at 10.6 mm with pulse durations between 0.1 and 100 ms and sub-ablative fluence. Our results indicate that short pulses with durations much larger than the characteristic acoustic relaxation time of the material can still cause high stress transients at the irradiated site, and indicate that pulse durations of the order of 10 ms may be more adequate both for enamel surface modification and for ablation than pulse durations up to 1 ms. The model presented here can easily be modified to investigate the dynamic response of ceramic materials to mid-infrared radiation and help determine optimal pulse durations for specific procedures.