PhD Thesis, Miguel Martínez Calderón
Miguel Martínez Calderón
Title: Ultrafast laser micro/nano fabrication of advanced material surfaces
Defense Date: 25/5/2018
Director: Santiago Miguel Olaizola Izquierdo and Mikel Gomez Aranzadi
Femtosecond laser based material processing is a cutting edge technology, which has emerged as a very useful and innovative tool in order to generate new surface advanced properties on a large list of materials. A good understanding of this technology allows the fabrication of surface structures ranging from a few hundreds of nanometers up to hundreds of microns, which are generated by carefully tuning the laser parameters and taking advantage of different phenomena related with laser-material interaction. Indeed, the generation of these type of structures together with the main advantages related to ultrashort pulse laser material processes (minimum material heating or structural changes, processing in open atmosphere, avoiding of coatings or chemical treatments, harmlessness for mechanical properties, etc) has been proved to be extremely useful in applications for many different industry and research fields such as biomedicine, photonics, tooling industry, energy generation or aerospace engineering.
In this framework, this thesis presents a multidisciplinary approach for the development of a high control of femtosecond laser technology and its use for the generation of new and improved material surface properties on high added-value products. Specifically, three different applications have been studied with a high degree of success:
The first application consisted in the fabrication of surfaces with improved wettability properties. We were able to fabricate metallic surfaces with superhydrophobic properties by only modifying the surface (on the micro and nanoscales) with femtosecond laser material processing. Superhydrophobic metallic surfaces are extremely interesting for applications such as heat exchange, corrosion resistance or drag reduction among many others, giving this result a high value and potential.
For the second application we exploited the capability of surface micro/nano structuring to modify metallic biomaterials integration. In this regard, with the fabrication of micro/nano patterns we were able to control the cell migration and adhesion, resulting in a technique that could serve as an effective way of improving biomaterial compatibility.
The third application was focused on the nanostructuring of artificial diamond surfaces in order to take advantage of its incomparable material properties together with the added value that suppose having the capability of precisely nanostructure the surface.