Product Code: ICA10_M1202

Micropillar Fabrication on Bovine Cortical Bone by Direct Write Femtosecond Laser Ablation
Authors:
Y. C. Lim, Laboratory for Multiscale Processing and Characterization, The Ohio State University; Columbus OH
K. Altman, Laboratory for Multiscale Processing and Characterization, The Ohio State University; Columbus OH
Dave Farson, Laboratory for Multiscale Processing and Characterization, The Ohio State University / Center for Affordable Nanoengineering of Polymeric Biomedical Devices, The Ohio State University; Columbus OH USA
K. M. Flores, Department of Material Science Engineering, The Ohio State University; Columbus OH USA
Presented at ICALEO 2010

This work investigated fabrication of cylindrical micropillars on bovine cortical bone using direct-write femtosecond laser ablation. The ablation threshold of the material was measured by single-pulse ablation tests and incubation coefficient was measured from linear scanned ablation tests. A motion system was programmed to apply multiple layers of concentric rings of pulses to machine pillars of various diameters and heights. The diameter of the top surface of the pillar was found to steadily decrease due to incubation of damage from successive layers of pulses during the machining process. Pillar top diameter was predicted based on a paraxial beam fluence approximation and single-pulse ablation threshold and incubation coefficient measurements. Pillar diameters predicted as successive layers of pulses were applied were well-matched to experiments, confirming that femtosecond laser ablation of the cortical bone was well-modeled by single-pulse ablation threshold measurements and an incubation coefficient.