Friction embossing

Abstract

A new fabrication process for micro structures from thermoplastic polymers is presented. Two layers of thermoplastic polymer are placed onto a tool with micro structures. By a friction welding machine, the polymer surfaces are rubbed against each other generating friction heat and melting the polymer. The polymer adapts to the surface shape of the micro structures on the tool. Then, the movement of the machine stops and the polymer cools down and hardens in the shape of the micro structures. The entire process is finished within a few seconds and the required investment costs are in the range of some 10,000 € to approximately 200,000 €. Compared to ultrasonic hot embossing, samples with larger overall dimensions can be fabricated and the heat distribution has been proven to be more homogeneous.

PVDF Sensor Foils Employed to Measure Shear Stress and Temperature of Friction Welding

“…The method presented here is not limited to friction welding but may enable measurements in a lot of applications where changes of temperature, shear, pressure and forces need to be known at the interface of bodies in close contact. One example is the new developed process friction embossing employed for the fabrication of micro structures from polymers [ 35 ].…”