Replication and Tribological Engineering of Physical Surfaces Using Two-Photon Lithography

Student: Shelby Maddox

Degree: Ph.D., May 2021

Major Professor: Dr. Min Zou

Research Area(s):

Conventional Materials & Processes

Nanoscience & Engineering

Replication techniques are difficult to apply to many biosurfaces, and large amounts of data are difficult to process for fabrication.
Nearly 10% of all automotive energy waste comes from the interface between the piston compression ring and the cylinder liner.
There is a need to reduce this friction using surface texturing

A digitization and tiling process is applied to scanned height data to reduce processing need and expand replication capability.
Hierarchical textures can be combined with biomimetic designs.
Inspiration from nature can be used to improve friction.

.Approach

Learning from nature

What biostructures do natural surfaces use to reduce friction?
The designs are created with 3D modeling software. Two photon lithography to create physical structures
Printing process allows quick turnaround of testing and development cycle.
Truly 3D surfaces can be created not just extruded shapes. Digitization and replication by tiling
Digitization of surfaces allows non contact replication of topographies.
Other fields using tiling processes to generate large outputs from small inputs.

Results show significant friction reduction due to special combination of surface features, published in Journal of Tribology.
Paper published in Journal of Manufacturing Processes on surface replication of biological surfaces, and in Biointerphases on friction reduction from those surface topographies.

Quick testing cycle of parameter-modified surfaces before robust, complex fabrication.
Reduction of friction in lubricated interfaces.