Cemented carbides, namely WC-Co, are the most widely used materials in cutting tools, due to its inherent high hardness and toughness, high mechanical strength and superior wear resistance. Powder metallurgy routes, i.e., milling, pressing and sintering are industrially used to process WC-Co parts, since by other processing routes the required specific properties are difficult to achieve. However, precise surface geometric features are difficult to attain by uniaxial pressing, and therefore subtractive processes, as machining are required. The high hardness and wear resistance attained by WC-Co parts after sintering process, makes the machining very expensive and time consuming, due to low material removal rate. In addition, commonly resulting in poor surface finish and high tendency to initiate micro cracks.
In recent years, laser technology has emerged as a promising surface modification technique with huge potential for application in a wide range of areas. Laser surface modification presents several advantages over traditional technologies, since it is performed without contact, there is no tool wear, tool breakage, chatter, vibration and deflection, and mechanically induced tool damage. Furthermore, laser surface modification allows great flexibility for producing several surface geometries, including complex shapes.
In the present study, pulsed laser ablation was applied in WC-Co substrates, in order to investigate different scanning strategies and combinations of laser parameters to obtain different types of surface geometries, such as textures, micro-grooves and cavities. The surface characterization was performed by 3D optical profilometry and scanning electron microscopy. Also, SEM was used to evaluate the influence of laser interaction on the WC-Co microstructure.