Effect of laser irradiation conditions on the laser welding strength of cobalt­chromium and gold alloys

Using tensile tests, this study investi­ gated differences in the welding strength of casts of cobalt­chromium and gold alloys resulting from changes in the voltage and pulse duration in order to clarify the optimum conditions of laser irradiation for achieving favorable welding strength. Laser irradia­ tion was performed at voltages of 150 V and 170 V with pulse durations of 4, 8, and 12 ms. For cobalt­ chromium and gold alloys, it was found that a good welding strength could be achieved using a voltage of 170 V, a pulse duration of 8 ms, and a spot diameter of 0.5 mm. However, when the power density was set higher than this, defects tended to occur, suggesting the need for care when establishing welding condi­ tions. (J Oral Sci 53, 301­305, 2011)