Chemical Engineering Seminar- Scalable Manufacturing of Hierarchical Composites for Multi-functional Aerospace Applications

Link for remote attendance: https://epfl.zoom.us/j/586806476

The goal of our laboratory is to enable bulk application of novel multi-scale engineered materials (polymer nanocomposites, ceramics, and metals) in next-generation structures, devices, and systems in extreme environments including aerospace applications.  In this talk, three on-going research projects will be presented.  First project is about controlled integration of nano-reinforcements to reinforce fiber-reinforced plastics. Nanofillers are organized in a tunable manner by taking advantage of oscillating magnetic fields, or magnetic attraction and repulsion. The critical effect of nanofiller contacts/interfaces on transport properties and scalable manufacturing such nano-reinforced composites will be discussed. Second project is about hierarchical structuring of ceramic composites to achieve toughening with "soft" boundary phases. Among many aerospace ceramics, boron carbide is of interest because it is light-weight, thermally stable, hard/stiff, and multi-functional (semiconducting, thermoelectric, and high neutron absorption cross-section), but brittle and is difficult to sinter.  A hierarchical structure was designed to have of micro-grains with soft interfaces for toughening without weakening, and was achieved with field assisted sintering technology with its rapid heating rate and thus improved diffusion. Third project is about functional grading of Ni-based superalloy turbine blades. Again, field assisted sintering was used to powder-sinter and bond superalloy of dissimilar crystalline for improved performance. Bulk application of these new materials is currently limited due to incomplete processing-structure-property relationship studies, and lack of scalable manufacturing technology.  We work to fill in these gaps, evaluate how nano-scale behaviors are translated to macro-scale properties, and establish the design space and certification process to achieve application of these novel materials.