A day after my Ph.D graduation held in the UiO Aula, I packed my bags and left Njord for my 2-years FRIPRO Mobility to AIP TU Wien. I was welcomed by a bunch of enthusiastic interface scientists and set out to work on my first individual fellowship (from the Research Council of Norway) in one of the best SFA labs!
But what is the whole project all about? Titled ‘‘Solid-solid interfaces as critical regions in rocks and materials: probing forces, electrochemical reactions, friction, and reactivity”, the project aims to investigate key interfacial processes that contribute to the mechanical strength of granular solids. Often, the overall strength of such solids is associated with what happens in tiny spaces between contacting individual grains. These are frequently the most reactive regions, in which minerals can grow or dissolve in the presence of water or more concentrated salt solutions. The growth and dissolution frequently determine if contact will be strong or weak, as they may cement solid grains together or push the grains away from each other. Thus, the overarching goal I set for this project is to recognize which of these processes make the solid-solid interfaces weak, and how to convert the weak interfaces into the strong ones.
Although we see the destructive effects of weak interfaces at a macroscopic scale (earthquakes, rock compaction and subsidence, general material failure), the very mechanisms governing the interfacial strength are frequently operating at much smaller scales (10-9m). To learn about these mechanisms, and to be able to modify them, we need new analytical methods that enable us to investigate the relevant nano and micro-scale processes. In my experimental project, I’ve chosen to work with the Surface Forces Apparatus (SFA). SFA allows studying of a multitude of interfacial processes, and all in one go: surface forces (adhesion and repulsion), friction between surfaces that move laterally, surface reactivity or even electrochemical surface corrosion! If you are looking forward to reading more, stay tuned, and follow the project’s progress!