Focusing the laser-scanator module of the SLM printer using an optical control system

Selective laser melting (SLM) is a promising technology for additive manufacturing of complex-shaped parts. Metal powder is used as a starting material, and a laser is used to melt and build up parts layer by layer. During the growth of parts, defects may occur that can only be detected after the manufacturing process is completed using third-party equipment, but which have a strong impact on the quality of the parts. Therefore, methods of non-destructive in situ quality control of the product are being developed, e.g. optical methods. But the use of such tools is only possible when all machine components of the printer's SLM, on which the optical control (OCS) and feedback systems rely on, operate normally. This paper presents a new technique for calibration laser-scanator systems using an optical tomography system, one of the optical control systems. Thus, a SLM printer equipped with OCS can become an automatically calibrating tool capable of operating with minimal involvement of a technologist.