The Effect of Laser Surface Remelting on the Surface Properties of Copper

Abstract

In order to enhance the wear resistance of copper contacts in high-voltage switches and improve the abnormal discharge phenomenon caused by wear gaps, laser remelting technology was used to strengthen the surface of copper contacts. The surface morphology, microhardness, and wear resistance of the remelted samples were tested and characterized using scanning electron microscopy (SEM), microhardness tester, and friction and wear tester. The test results indicate that laser frequency, pulse width, and energy density parameters can directly affect the surface morphology and wear resistance of the sample, but their influencing processes vary. The laser frequency is achieved by the variation in the superposition relationship between the impact points, while the pulse width and energy density are achieved by the variation in the laser intensity at the impact points. When the pulse frequency is 10 Hz, the pulse width is 10 ms, and the energy density is 132.69 J/mm2, the sample exhibits a more balanced surface morphology, microhardness, and wear resistance.