Investigations into quality assurance of plasma-welding corrosion-protective cladding using on-line element-spectrometry

摘要

Cladding of high-grade corrosion resistent protective layers by means of plasma-welded claddings is applied with great success if the geometry and size of the workpiece restricts the application of other coating-techniques.Especially if Ni-alloys which are sensitive to dilution are to be used the corrosion. resistance is however reduced by changes of the chemical composition. By means of process optimization and a continuous control an evenly distributed and minimizeddilution can be achieved.With a direct measuring of the element concentration in the weld pool of the plasma welding process it is attempted to improve process-control and quality assurance. The pursued aims in this respect are an increase of the performance of an on-line element spectral analysis of the plasma arc and their employment in the field of welding engineering. This contribution gives an overview of the conditions for an effective analysis method, requirements for the measuring set-up and the actual process as well asanalytical approaches.