An approach to producing interfaces with tailored and repeatable normal contact stiffness using micropatterned surfaces is developed. A finite element model is first used to design square wave interfaces having a range of stiffnesses and these are fabricated in polycarbonate via a microfabrication process. Results demonstrate that the contact stiffnesses of the fabricated interfaces are both tailorable and repeatable. The approach can be broadened to other materials and is useful for applications requiring specified interface stiffness. Finally, even with these deterministic interfaces, we show that low levels of roughness on the surface features is sufficient to produce a load-dependent contact stiffness at lower loads. Therefore, tailorability is mostly applicable above this limit where total contact stiffness converges to a load-independent value.
The authors would like to acknowledge the support of the Leverhulme Trust for funding the work via project grant “Fundamental Mechanical Behaviour of Nano and Micro Structured Interfaces” (RPG2017-353). The Leverhulme Trust are also acknowledged for providing the PhD studentship for the first author. We would also like to thank the technical staff at the James Watt Nanofabrication Centre (JWNC) at the University of Glasgow for assistance in fabricating the samples. Mr Alex Hamilton is thanked for useful discussions throughout the work.
Funding (Leverhulme Trust Project Grant No. RPG-2017-353)
Data Availability StatementData will be made available via an online university data repository.
- contact stiffness
- structured surfaces