PROCEDURES AND REQUIREMENTS FOR OPTICAL QUALITY CONTROL IN LABORATORY SWITZERLAND

摘要

A procedure for optical quality control in laser application welding, whereby in the laser application welding process the surface (20) of a workpiece to be coated (2) by means of a surface treatment stain (24) directed at the surface (20) and focused by a focus optic (16) high energy laser beam (14)melting, which produces a melting bath (26) in the treatment stain (24), and where a powder coating material is applied to the melting bath (26) in the treatment stain (24), includes the following steps:(a) capture the electromagnetic radiation emitted by the melting bath (26) as light (47) by means of an imaging device (40), the brightness of the light emitted representing the intensity of the electromagnetic radiation emitted;(b) transfer the recorded image information of the melting bath (26) to an image evaluation unit (42);(c) computing the location data of at least one area (28) of equal intensity and/or of at least one area within a certain intensity interval in the recorded image information to form a contour of the area;(d) assign at least one symmetrical surface body (E) to at least one area (28) of equal intensity by approximating a geometric figure to the contour of the area;(e) identify characteristics characteristic of the geometric shape of at least one symmetrical surface body (E);(f) storing the characteristics of at least one symmetrical surface body as a record in a data storage device (44); and(g) capture, control and/or monitor at least one parameter of the laser application welding process affecting the quality of the coating by means of a process control device (46) based on the data of the characteristics of at least one symmetrical surface body (E).