Experimental investigation of laser texturing on surface roughness and wettability of PAHT CF15 fabricated by fused deposition modeling

Abstract

Fused deposition modeling (FDM) process has been emerged as an effective method for fabrication of different types of products without the need for expensive molds or material wasting subtractive processes. Polyamide composites possess higher mechanical properties, temperature resistance and inertness to many chemicals making them an attractive choice for many applications. This study focuses on the utilization of a nanosecond fiber laser texturing process as a post processing method for improving the surface finish and surface hydrophobicity of polyamide composite (PAHT CF15) produced through FDM process. PAHT CF15 is a high temperature resistant polyamide filament with 15% carbon fiber. These effects of texturing direction on surface finish and wettability of FDM printed PAHT CF15 samples were evaluated by texturing in two mutually perpendicular directions namely longitudinal and transverse. Experiments were also performed to determine the effect of laser power and scanning speed by varying the power at four levels, that is 20, 30, 40, and 50 W and scanning speed at two levels, that is 2000 and 4000 mm/s. Moisture absorption test of the textured surfaces were performed in an incubator at controlled temperature and relative humidity condition. A defocused laser beam was utilized to melt the upper surface of the 3D printed material in order to bring the changes at the surface level without causing surface ablation. It was observed that high speed laser processing can bring about the significant changes in surface finish, wettability and moisture absorption of the FDM printed parts.Highlights PAHT CF15 composites possess excellent mechanical properties. FDM printed PAHT CF15 parts have poor surface finish and low contact angles. Fiber lasers were employed to improve surface roughness. Wettability of textured surfaces was decreased by a maximum of 46%.