The advantages of the femtosecond laser for micromachining of materials have been widely demonstrated allowing the laser micromachining to reach a level of accuracy in the micrometer range level. However, most of the current femtosecond laser micromachining applications are for flat surfaces, 2D or 2.5D, requiring different kinds of machining: drilling, cutting, and texturing, for more and more exotic materials. Biomedical implants are a part of those new objects requiring very high level of accuracy and surface finish, and for complex geometries: cylindrical or hemispherical shapes. LASEA has developed a system combining femtosecond laser with 7 simultaneously moving axes: 5 mechanical axes and 2 galvanometric axes. This combines the 3D micromachining offered by the 5 axes with the fast scanning. The laser parameters and strategies are controlled owing to laser specific developed functionalities. Another challenge to overcome is the research of laser parameters which is time and material consuming. In order to make this research more efficient, LASEA has developed a tool named LS-Plume which simulates the profiles for different sets of parameters.
In this work, we focus mainly onto biomedical implants, such as stent cutting and hip implants texturing. The characterisation of the stents was carried out based on computed X-ray tomography, after processing and balloon inflation. Fast texturing of 3D part is also demonstrated and evaluated. Different biocompatible materials have been characterised and used by the tool LS-Plume. Showing a good match between a simulated and measured profiles.
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