Design and application of laser scanning strategy for machining deep surface grooves with a continuous-wave fiber laser

Abstract

A laser scanning strategy for fabricating deep surface grooves using a continuous-wave fiber laser was investigated in this study. Because the low productivity of short-pulsed-wave lasers limits their application to a small scale, a continuous-wave (CW) fiber laser that can provide a high power density was used for rapid fabrication of deep grooves. An innovative tailored laser-scanning strategy of fabricating patterned deep grooves was analytically designed based on the power density and interaction time. Considering the thermophysical properties of the material, controlled laser processing parameters were determined for fabricating surface grooves with rectangular and chevron cross-sectional patterns. To confirm the usefulness of the research results, the scanning strategy obtained in this study was applied for achieving high-quality joining between injection-molded metal-plastic hybrids (MPHs). A deep-surface-grooved A5052 aluminum alloy sheet was bonded to two plastics, polyamide and polypropylene, via injection molding. Lap shear tensile tests of the MPHs revealed their significantly enhanced joining strength owing to a better mechanical interlocking of the groove. The developed laser scanning strategy using a CW fiber laser can be widely applied in the fabrication of deep grooves of various cross-sections with high reliability.