Chapter 6 - Laser Processing Diagrams

Abstract

Charts and diagrams can be constructed for a range of engineering materials that describe the conditions required to achieve the principal thermal mechanisms of laser processing—heating, melting, or vaporization. The simplest are charts based on empirical data. The framework (axes) of an empirical chart can be established by considering the principal process variables. By plotting experimental data in such a framework, processes may be compared and groups of processing parameters that influence the processing mechanisms can be elucidated. Empirical charts provide insight into the principles of a process, and are often the first stage in understanding the underlying physical principles. But processing parameters can only be derived from empirical charts. The basis of a model-based diagram is a physical model that describes the functional relationships between the principal process variables (axes). The model provides a diagram with predictive capability. Such modeling reveals fundamental dimensionless groups of process variables, which simplify analysis while maintaining the level of accuracy required.