Molecular Dynamics Simulation of Fracture at a Polymer and Metal Oxide Joining Interface

Molecular dynamics simulations are used to study the fracture mechanism of the joining interface of a polymer and metal oxide. A polyphenylene sulfide (PPS) layer is sandwiched between two plates of aluminum oxide and one of the plates is pulled to simulate fracture under tensile force. The stress-strain curve for the polymer-metal interface is similar in shape to the stress-strain curve for constant cross-sectional strain in bulk PPS. In the simulations, fracture of the polymer-metal joint is initiated by the formation of small voids inside the polymer layer, which occurs at the yield point of the polymer-metal interface. Annealing prior to tensile loading is determined to enhance the joint strength.