The direct write laser-machining process is based on CNC technology and therefore it is assumed that the laser beam focal spot scans the workpiece surface in conformance with the predetermined tool path. However, laser- machining experiments indicate that the geometric quality of the machined part is not only defined by the pre- determined tool path but is also largely influenced by the dynamics of the laser-material interactions. The geometry and surface profile of the machined part is the result of a combined effect of the complex dynamic processes accompanying the machining process. All laser-machining systems have unique dynamic characteristics, represented by random variations of process parameters, e.g., pulse energy, travel speed, etc. Thus, accurate prediction of part quality becomes very difficult, requiring a systematic experimental study for each specific material and the laser-machining system. The objective of this work is to experimentally investigate the effect of variations in laser pulse energy on the geometric quality of the machined parts in terms of accuracy, precision, and surface quality.
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