Experimental Study on Physical Parameters Involved in Laser Welding of CO-CR Alloys

Introduction: The quality of laser weldings in dental laboratory depends on the control of many parameters. The aim of the study was to find the optimal parameters related to the framework defect. Materials and methods: To evaluate the welding parameters several Co-Cr framework defects were simulated. Depending on the defect size, a pulsed Nd:YAG laser was used for joining and for build-up welding. Results: The physical parameters were determined for each step. The peak power was determined as 900W for fixing, 700W for filling and 600W for planing of the joints. The pulse duration was established as 10ms for fixing and planing and 20ms for build-up. The pulse energy was 8J for fixing, 14J for filling and 6J for planing. The diameter of the laser spot was maintained constant at 0.6mm. Conclusion: Selecting adequate combination of pulse energy, pulse duration and peak power for each step is necessary for the succes of the welding procedure. Keywords: laser welding, Co-Cr alloys, welding parameters