INFLUENCE OF THE TYPE OF KINETIC FUNCTIONS ON CONVERSION IN A THIN LAYER PLACED ON A SUBSTRATE UNDER THE CONTROL OF A MOVING HEAT SOURCE

Advanced combined laser technologies assume a conjunction of surface treatment capabilities with material synthesis. In this case, preliminary temperature estimations based only on thermophysical models are unreasonable. It is necessary to consider chemical reactions that can take place both in solid and liquid phases. For this purpose, we present a brief review of reactions involving solids and types of kinetic functions that are used to process experiments in chemistry and chemical kinetics. A variety of kinetic functions provides a wide range of possibilities for analyzing experiments, which contributes to a deeper understanding of the processes involved. Further, on the basis of a one-dimensional reduced model with a total chemical reaction and taking into account the accumulation of the liquid phase, we show that the type of kinetic function, which reflects the reaction mechanism at the microlevel, affects both the maximum temperature and the degree of the reaction’s completion. Reduced models allow us to investigate each factor under study more effectively, which can subsequently be useful for the process optimizations. For the Al+TiO2 system, we present dependences of characteristics of the quasistationary stage on parameters reflecting the role of the synthesis conditions. In this system, the transformations can be described with two total reactions: the first gives the hardening phase, the second leads to a change in the matrix composition. The dependence of the maximum temperature on the power density of the heat source appears to be linear. After processing, the coating contains both reaction products and initial substances. The specific composition is determined by the processing conditions.