Spatial chaos aspects of laser-material interaction

In the past decade the understanding of stability and chaotic behaviour of nonlinear systems has made significant progress. Such systems include: structure of turbulence, oscillations in mechanical structures, multistable biological systems, etc. Laser machining is now an established industrial production method for: prototyping, small batch manufacture, cutting refractory materials and specialist applications such as micromachining. Within narrowly bounded limits, many models exist that can be used to predict the necessary machining control parameters such as cutting rate, power, pulse repetition frequency, etc. However, in an unconstrained machining process, chaotic phenomena can be observed to occur. The objective of this paper is to prove the existence of chaos, for the laser-material interaction, which can be described by Poincaré-Birkhoff-Smale horseshoes. Furthermore, to exploit the phase portrait of the process to predict the optimal laser machining control parameters. © 1994