The Thermal Damage Research Of Optical Materias Under Millisecond-pulsed Laser Irradiations

The thermal damage of high energy laser has important application in modern times industry and military. The technique of using laser thermal damage to melt or boil away port of materials and then cooling fuse is called laser jointing. High-speed assistant airflow blows the melted or boiled materials in order to form incision or aperture, which is defined laser incision or laser stiletto. Laser has incomparable power in weapon manipulative system, high power laser weapon can destroy airplane or tank in a millisecond, and can demolish the exploring portion of the missile being accurately controlled and guided. Many domestic and overseas researchers have investigated laser thermal damage under nanosecond-pulsed, but there has been few report of laser thermal damage under millisecond-pulsed laser irradiations. The thermal damage under millisecond-pulsed laser irradiations has been investigated in this thesis in detail. The temperature of some metal materials and semiconductor materials have been described, and the melting damage threshold and boiling damage threshold were calculated. The main results have been summarized as follows:1. The factors that affect the damage conformation and damage threshold have been studied, and damage mechanism has been analyzed in the thesis.2. A simple approximate mathematic model of one-dimensional laser thermal damage has been discovered, the temperature field and melting damage threshold and boiling damage threshold of metal materials have been accounted.3. The analytic method of the problem of thermal conductor equations has faulty...