Despite their importance in geotechnical applications and in geological processes, the swelling behavior of rocks is still insufficiently understood, while its effects at the scale of engineering projects are significant. This joint research will bring together the experimental and modeling skills of French and German partners to characterize, understand and model the macroscopically observable effects of rock swelling from microscale processes. The planned research will focus on clay-sulfate rocks, where swelling of the clay phase and chemical swelling can occur together and influence each other. If the volume increase is hindered, high swelling pressures can occur. The thermal (T), hydraulic (H), mechanical (M) and chemical (C) processes that take place in this process, and in particular their mutual influence (THMC coupled processes) are not yet sufficiently understood. Consequently, construction projects in clay-sulfate rock today are still prone to imponderable risks. The overarching goal of the proposed research is to generate experimental results that quantitatively characterize the THMC coupled swelling behavior of geological material, using clay-sulfate rocks as experimental material, and translate those results into constitutive equations usable in numerical simulations at the geological structure scale. To reach the project goals, we have structured the planned research into four tasks. The first three tasks are experimental and will be used to inform the engineering models developed in Task 4. Task 1 includes the preparation of the samples, i.e., natural samples of clay-sulfate (anhydrite) rocks. We will characterize in Task 2 how those samples swell and their permeability evolves when water flows through them. These experiments will be performed with flow-through cells. Task 1 will also include characterization of the samples before and after the swelling experiments in Task 2, to detect mineralogical changes. Both quantitative mineralogical analysis (by X-ray diffraction, Rietveld method, and thin section analysis) and chemical composition analysis (by X-ray fluorescence spectrometry) will be performed. Fluid samples taken during the swelling experiments of Task 2 will also be analyzed (by microwave plasma atomic emission spectrometry and titration). To understand and interpret the processes behind the macroscopically observable swelling behavior, advanced imaging of the samples at a smaller scale will be performed in Task 3. We will use X-ray computed microtomography (XRCT) and magnetic resonance imaging (MRI) to make direct observations of pore structure and fluid flow and their changes during swelling. Moreover, chemical reactions can be tracked in space and time contemporaneous with swelling by observing changes in pore space, density and water content. These experiments will be complemented by scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP) and, potentially, NMR cryoporometry. The results will enable us to tell where and when both fluid flow (e.g., rock matrix versus discontinuities) and chemical swelling (location and time of conversion) occur, and how they are related to mechanical (e.g., density/volume) and hydraulic (e.g., porosity, flow rate) parameters. Data gathered in Tasks 1, 2, and 3 will serve as a basis for the model development, calibration, and validation in Task 4. Elastoplastic THMC constitutive laws will be either calibrated on the set of data obtained in Tasks 2 and 3 for the specific rock tested, or predicted by Fast Fourier Transform from the microstructural observations performed in Task 3. These constitutive laws will be implemented in two open-source finite elements codes that make it possible to perform THMC calculations (code Bil and OpenGeoSys coupled with the geochemical calculator PhreeqC) and validated on the flow-through swelling experiments of Task 2. The two numerical approaches will be compared with each other.

Compressed fluid systems handled in high pressure processes feature diffusivities smaller than the kinematic viscosity. Therefore during mixing the lifetime of micro(µ)-scale(s) inhomogeneities exceeds that one of macro(m)-scale(s) inhomogeneities. Thus m-s homogeneous systems can still exhibit µ-s inhomogeneities. They affect the functioning-chain of processes, e.g. reactions and phase-transitions or –separations, which themselves also take place on a sub-macro-scale. Therefore it will be analyzed in situ how µ-s inhomogeneities influence the functioning chain of the particle generation (supercritical antisolvent technology), the reaction (high pressure combustion), and the phase-separation or phase-transition mechanisms (surfactant-free CO2-based micro-emulsions and gas hydrates) and to which extend these inhomogeneities are responsible for the characteristics of the product, such as unfavourable size distributions of particulate products and/or pollutant emissions. On this purpose the here proposed and self-developed non-invasive and in situ Raman spectroscopic technique considers the INTENSITY-ratios of Raman signals to analyze the m-s composition and the SIGNATURE of the OH stretch vibration Raman signal of water (or alcohols) to analyze the µ-s composition of fluid mixtures. The SIGNATURE of the OH stretch vibration Raman signal is influenced by the development of the hydrogen bonds -an intermolecular interaction- and thus provides the µ-s composition, though the probe volume of the Raman sensor is m-s. The signal-INTENSITY-ratio and signal-SIGNATURE are extracted both from one and the same “m-s” Raman spectrum of the mixture. This allows the comparison of the degree of mixing on m-s and µ-s simultaneously, and enables the analysis of whether a system at any instance of mixing (instance of the onset of a reaction or a phase transition or –separation) has reached the favourable µ-s homogeneity, which would result in homogeneous and uniform products.

After decades of truly transformative advancements in single molecule (bio)physics and surface science, it is still no more than a vision to predict and control macroscopic phenomena such as adhesion or electrochemical reaction rates at solid/liquid interfaces based on well-characterized single molecular interactions. How exactly do inherently dynamic and simultaneous interactions of a countless number of interacting “crowded” molecules lead to a concerted outcome/property on a macroscopic scale? Here, I propose a unique approach that will allow us to unravel the scaling of single molecule interactions towards macroscopic properties at adhesive and redox-active solid/liquid interfaces. Combining Atomic Force Microscopy (AFM) based single molecule force spectroscopy and macroscopic Surface Forces Apparatus (SFA) experiments CSI.interface will (1) derive rules for describing nonlinearities observed in complex, crowded (water and ions) and chemically diverse adhesive solid/liquid interfaces; (2) uniquely characterize all relevant kinetic parameters (interaction free energy and transition states) of electrochemical and adhesive reactions/interactions of single molecules at chemically defined surfaces as well as electrified single crystal facets and step edges. Complementary, (3) my team and I will build a novel molecular force apparatus in order to measure single-molecule steady-state dynamics of both redox cycles as well as binding unbinding cycles of specific interactions, and how these react to environmental triggers. CSI.interface goes well beyond present applications of AFM and SFA and has the long-term potential to revolutionize our understanding of interfacial interaction under steady state, responsive and dynamic conditions. This work will pave the road for knowledge based designing of next-generation technologies in gluing, coating, bio-adhesion, materials design and much beyond.

Additive manufacturing (AM) has the potential to drive novel industry development as well as to transform current industries, but exploiting it to the fullest requires professionals with advanced degrees who have received the highest-level training in both technical and non-technical competences. The University of Ljubljana has expertise in the direct laser deposition (DLD) process, but has several weaknesses in the areas addressed in the SEAMAC project, including material behaviour especially to master the manufacturing of functionally graded materials and to perform postprocessing of AM parts to improve surface roughness. Hence, leading scientific institutions, namely Technion - Israel Institute of Technology and Technische Universiteat Bergakademie Freiberg take part in the consortium. The former brings expertise in material science and the latter the knowledge on plasma electrolytic polishing. Both institutions are very active in the AM field, have a lot of cooperation with industrial partners, and are skilled in research management. The project activities encompass technical and non-technical cooperation and exchange of knowledge through the workshops and organisation of summer schools.

Crystalline defects in metals and semiconductors are responsible for a wide range of mechanical, optical and electronic properties. Controlling the evolution of dislocations, i.e. line-like defects and the carrier of plastic deformation, interacting both among themselves and with other microstructure elements allows tailoring material behaviors on the micro and nanoscale. This is essential for rational design approaches towards next generation materials with superior mechanical properties. For nearly a century, materials scientists have been seeking to understand how dislocation systems evolve. In-situ microscopy now reveals complex dislocation networks in great detail. However, without a sufficiently versatile and general methodology for extracting, assembling and compressing dislocation-related information the analysis of such data often stays at the level of “looking at images” to identify mechanisms or structures. Simulations are increasingly capable of predicting the evolution of dislocations in full detail. Yet, direct comparison, automated analysis or even data transfer between small scale plasticity experiments and simulations is impossible, and a large amount of data cannot be reused. The vision of MuDiLingo is to develop and establish for the first time a Unifying Multiscale Language of Dislocation Microstructures. Bearing analogy to audio data conversion into MP3, this description of dislocations uses statistical methods to determine data compression while preserving the relevant physics. It allows for a completely new type of high-throughput data mining and analysis, tailored to the specifics of dislocation systems. This revolutionary data-driven approach links models and experiments on different length scales thereby guaranteeing true interoperability of simulation and experiment. The application to technologically relevant materials will answer fundamental scientific questions and guide towards design of superior structural and functional materials.