Damage and thermal response of materials to pulsed thermonuclear irradiation

This thesis is devoted to the development of more precise models for the calculation of damage and thermal responses of materials to the irradiation and implantation of different radiation species. The radiation species of concern are the X-rays and ions generated in inertial confinement fusion (ICF) reactors.; D-PULSE is a computer program developed to study the damage response of materials to energetic ions. The materials can be pure or multi-component. The program can analyze low ion fluence cases in which the modification of the target materials due to the implanted ions is negligible. With the inclusion of preferential sputtering and implanted ions accumulation effects, the program can also analyze high ion fluence cases. The thermally activated processes (such as radiation enhanced diffusion and radiation induced segregation) and the temperature rise due to the energy deposition of the implanted ions are also featured in the program.; T-PULSE is a computer program proposed for a general analysis of the thermal responses of materials to pulsed X-rays and ions. The energy deposition rate can be of a single pulse form or a multi-pulse sequence, which allows simultaneous combinations of X-rays and ions with various spectra and energy ranges. In essence, this program solves the heat conduction equation by use of a finite-difference method. Variations of thermophysical properties with temperature for both liquid and solid phases are included. The simulation of two moving boundaries due to melting or solidification at the solid-liquid interface and evaporation or condensation at the exposed surface is also incorporated into the program.; D-PULSE has been compared extensively with experimental data and two well-known computer codes, TRIM and BRICE. In addition to a satisfactory agreement with those experiments, D-PULSE presents better predictions than those obtained from TRIM and BRICE. Similarly, comparisons with exact analytical solutions, other available computer codes (A*THERMAL and DSTAR), and experimental data have been made to validate the reliability of T-PULSE and all show good agreement. The applications of D-PULSE and T-PULSE have been demonstrated by parametrically analyzing thermal and damage responses of materials during pulsed ICF irradiation conditions. These results can also be extended to other more practical applications.