Numerical simulation of fibre growth in antitaxial strain fringes

A two-dimensional computer model ('Fringe Growth') is used to simulate the incremental growth of crystal fibres in undeformed antitaxial strain fringes. The user can define the shape of a corp-object (e.g. a pyrite crystal), the growth velocity and anisotropy of growing crystals, the rotation of fringes and core-object with respect to a horizontal datum and with respect to each other, and the opening velocity of fringes. Growth is simulated by movement of nodes connecting line segments that define the grain boundaries. Modelling results predict that face-controlled strain fringes will grow around smooth core-objects and strain fringes with displacement-controlled and face-controlled fibres around core-objects with rough surfaces. The surface roughness of the core-object determines if fibres in the fringes track the opening trajectory, since fibres follow asperities on the surface of the core-object. Rotation of the core-object and the fringes with respect to an external reference frame and with respect to each other influences the geometry of the fibres. Our modelling results indicate that fibre growth direction is not directly dependent on the orientation of the extensional instantaneous stretching axes or the finite maximum strain axes. (C) 2000 Elsevier Science Ltd. All rights reserved.