A finite element method for stress-assisted surface reaction and delayed fracture

When a stressed solid is in contact with an environment (a vapor or a liqui d solution), the solid may gain mass from, or lose mass to, the environment . The surface reaction is driven by the interfacial and elastic energy and by the chemical potential difference between the solid and the environment. This paper presents a finite element method to simulate the stress-assiste d surface reaction. The reduction of the total free energy associated with gaining unit volume of solid defines the driving force. A linear kinetic la w is adopted, where the reaction rate is proportional to the driving force. The problem is described with a variational statement. The elastic field i n the solid is solved repeatedly as the solid changes its shape. The solid shape is updated with a mesh adaptation procedure and according to the kine tic law. Numerical examples include shape changes of a wavy surface, and cr ack nucleation at a grain boundary. (C) 2001 Elsevier Science Ltd. All righ ts reserved.