Optimizing the surface of manufactured components for friction, adhesion, and convective heat transfer

The manufacturing process defines not only the component’s geometry, but also how its surface senses and interacts with the outside world via its topography. Every manufactured surface is rough, but the component can benefit from the roughness control. Topography in functional surfaces is optimized either by controlling the manufacturing parameters or by post-manufacturing surface patterning technologies. However, how are topographic features measured and characterized? How do rough surfaces contact each other? What happens if fluid is present at the contact interface? And what are the mechanisms that correlate surface topography and its functionalities? This article will cover the engineering of surface topography in manufacturing by addressing empirical advancements and scientific understanding in the field. The functionalities covered are adhesion, friction, and convective heat transfer. Relatively large surface structures used for heat transfer mainly take advantage of recent advances in additive manufacturing, while conventional manufacturing processes and deterministic surface patterning techniques are discussed for the control of adhesion and friction.