Steel: Medical Devices and Miniature Parts

(Pic1) microgear fabricated from a standard 25um sheet of stainless steel. 100 um inner diameter. (Pic2) SEM image of section of stainless steel tube by picosecond laser.

Numerous applications exist in which stainless steel and other tough alloys must be micromachined without defects such as burrs. WIth picosecond lasers, material removal rates can be achieved ranging from .05 to 0.2 mm^3/min*W. Shown above is a Micro gear produced for use in conjuncture with the micro fluidic mixer for secondary stage fluid mixing. Such tiny devices can be integrated to existing MEMS actuators. To ensure and smooth operation on these sensitive devices, the edge quality must be burr-free. Difficulty in fabrication of such pieces include handling and removal of debris from the cutting process. In the above figure, the only post-production procedure employed is the use of cleaning tissue to remove debris generated from cutting.Eexisting microgears made from silicon, often suffer from debris formation due to wear and tear over time. Stainless steel gears promise to be much tougher and significantly more durable, reliable and can minimize or eliminate debris formation from wear and tear.