Abstract
Discrete Element Method (DEM) has been used for numerical investigation of sintering-induced structural deformations occurring in inverse opal photonic structures. The influence of the initial arrangement of template particles on the stability of highly porous inverse opal α-Al2O3 structures has been analyzed. The material transport, densification, as well as formation of defects and cracks have been compared for various case studies. Three different stages of defects formation have been distinguished starting with local defects ending with intrapore cracks. The results show that the packing of the template particles defined during the template self-assembly process play a crucial role in the later structural deformation upon thermal exposure. The simulation results are in very good agreement with experimental data obtained from SEM images and previous studies by ptychographic X-ray tomography.
Highlights
Photonic crystals and glasses are a class of materials with the capability of manipulating the electromagnetic radiation propagation and thereby, find application in solar thermophotovoltaic energy conversion devices and are prospected as next-generation reflective thermal barrier coatings [1,2,3]
On the one hand, such structures make it possible to analyze the influence of packing density. They can more realistically represent the defects occurring in self-assembled structures of polymeric template particles before burn-out, which are kept during the infiltration phase and later reproduced in the inverse structures generated after burn-out [35]
Usage of the graphics processing units (GPU) parallelization combined with the periodic boundary conditions has allowed to perform calculations in a reasonable time
Summary
Photonic crystals and glasses are a class of materials with the capability of manipulating the electromagnetic radiation propagation and thereby, find application in solar thermophotovoltaic energy conversion devices and are prospected as next-generation reflective thermal barrier coatings (rTBC) [1,2,3]. Ceramic-based inverse photonic structures have been produced using different techniques and various materials for the matrix such as silica [7], titania [10], alumina [12], mullite [13], zirconia [14] and yttria stabilized zirconia (YSZ) [7,15] When these structures are exposed to high-temperatures (> 1000 °C), though, they undergo morphological changes that may hinder their final function, especially in the case of photonic applications. The discrete element method (DEM) approach, implemented in the simulation framework MUSEN [21], has been used to analyze the structural deformations occurring in inverse opals photonic structures exposed to high-temperatures. This work focuses on the photonic materials application as next-generation reflective thermal barrier coating (rTBC), the structures exposed here have a high fraction of interconnected porosity, which makes them attractive for a variety of other technological applications, such as catalysts, solid oxide fuel cells and membranes [16,31,32]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
