Mechanics and Computation Group Research
Modeling and Simulation in Solids and Structures
Computational Aided-Engineering tools are widely used in engineering design nowadays and have become an integral part of the design cycle. However, any analyst using the tools will be aware of their predictive limitations for problems involving complex material behavior, failure, inelasticity and damage, phase changes, and changes in the domain (e.g., shape optimization, crack evolution). These shortcomings are all manifested in some of the areas of activity of the Group: additive manufacturing of metals and polymers, stretchable electronics at the interface of engineered and living systems, battery technology, hydraulic fracture and geophysics problems, and the design of advanced material systems, among others also described below.
The Group advances modeling and simulation knowledge and technology through the creation of new numerical methods for both physics-based and data-based modeling. The former includes finite element methods, mesh-free methods, dislocation dynamics, and advanced sampling method in atomistic simulations, and the latter encompasses machine learning and data-science techniques adapted and applied to solids and structures. Machine learning and data science offer the opportunity to go beyond empirical and phenomenological relations between physical quantities and identify new relations purely based on data, either from experiments or first-principle simulation data. They provide new avenues for probabilistic modeling when measurements or observations are sparse, noisy, and uncertain. Applications include the identification and modeling of the constitutive behavior of materials, as well as inverse modeling and optimization based on experimental and large-scale simulation datasets.
Experimental mechanics, advanced microscopy and characterization
“Seeing” phenomena previously limited to theory and characterizing the mechanical behavior at very small scales or of novel multifunctional materials are the current driving forces behind the Group’s effort in this area. Activities include the characterization of the nonlinear mechanical behavior of various polymeric materials and soft systems, nanostructured metals and alloys, and architected composites that are usually subject to thermo-mechanical coupled loading and finite deformation. To see new phenomena, the Group uses and develops new types of advanced microscopes—optical and X-ray—to resolve the multiscale behaviors of tiny defects that can cascade into bulk failure or strength in different environments. Advanced electron microscopy, X-ray diffraction and microscopy and optical spectroscopy are also used to understand structural changes at atomistic-to-continuum scales, including under extreme environments such as high pressure and in-operando conditions in renewable energy systems (e.g., green hydrogen, batteries). These activities also include exploring how extreme states of matter are generated as materials rapidly deform during shock waves, in systems relevant to aerospace and defense technology.
Advanced and Sustainable Manufacturing
Manufacturing is undergoing a revolution propelled by the democratization of design promised by additive manufacturing techniques (3D printing), the application of data science, and the increasing demand for sustainable manufacturing processes. The Group both creates novel ways to print metals and polymers, as well as uses 3D printing as an integral part of research efforts. Multiple additive manufacturing techniques, including direct-ink-writing, digital-light-processing, and fused filament fabrication, are integrated to print polymeric composites and soft materials. These efforts enable the manufacturing of advanced systems such as stimuli-responsive materials for soft robotics, morphing systems, self-assembled materials, strong and lightweight nano-architected materials, and materials with tunable structural and mechanical properties. To print very small structures, two-photon lithography is combined with novel resins to directly write nanoscale metals and ceramics. Finally, a metal 3D printer based on powder-bed fusion (PBF) technology provides the platform for fundamental research on the physical processes in metal printing, as well as for the manufacturing of metal parts with complex shapes for novel applications. The Group has a program to study process design for metal additive manufacturing, both to learn about the physics that gives rise to the unique properties of printed metals, as well as to enable the printing of novel materials demanded by novel applications, such as creating Copper micro heat exchangers and wave guides.
The Stanford High Performance Computing Center operates a number of HPC clusters to enable larger simulations, deeper analyses, and faster computation times than are possible using computers available to individual researchers. The HPC Center has mass data storage and archival systems to store the vast quantities of data the result from performing simulations on these HPC resources.
Learn more about our High Performance Computing Center.