The Analysis of Micro-Scale Deformation and Fracture of Carbonized Elastomer-Based Composites by In Situ SEM

Carbonized elastomer-based composites (CECs) possess a number of attractive features in terms thermomechanical and electromechanical performance, durability aggressive media facile net-shape formability, but their relatively low ductility strength limit suitability for structural engineering applications. Prospective applications such as elements micro-electro-mechanical systems MEMS can be envisaged since smaller principal dimensions reduce the susceptibility components to residual stress accumulation during carbonization brittle fracture general. We report results situ in-SEM study microdeformation behavior CECs based on nitrile butadiene rubber (NBR) elastomeric matrices filled with carbon silicon carbide. Nanostructured composite materials were manufactured via compounding substance SiC fillers using mixing rolling mill, vulcanization, low-temperature carbonization. Double-edge notched tensile (DENT) specimens vulcanized carbonized subjected testing chamber scanning electron microscope (SEM) Tescan Vega 3 Deben microtest 1 kN stage. The series acquired SEM images analyzed by means digital image correlation (DIC) Ncorr open-source software map spatial distribution strain. These maps correlated finite element modeling (FEM) simulations refine values elastic moduli. Moreover, moduli derived from unloading curve nanoindentation hardness measurements carried out NanoScan-4D tester interpreted Oliver–Pharr method. Carbonization causes significant increase 0.86 ± 0.07 GPa 14.12 1.20 graphite black fillers. Nanoindentation yield somewhat lower values, namely, 0.25 0.02 9.83 1.10 before after carbonization, respectively. analysis fractography suggests that crack initiation, growth propagation may occur both at notch concentrator or far notch. Possible response are discussed, (1) stresses introduced processing; (2) shape size fillers; (3) emanation gases