Method for determining strains, deformation and damage in workpieces composed of a solid material

Method for determining the effects of mechanical stress on an object composed of a solid material, according to which method the strains and stresses generated by the mechanical stress at a plurality of points in the object are calculated by means of a numerical calculation method in inelastic mode, in which the behaviour of the solid material is represented by a polycrystalline microscopic behaviour model using a plurality of “grain” blocks whose strains is determined on the basis of a plurality of slip systems peculiar to the solid material, the trace of the tensor of the microscopic strains being zero, each “grain” block having an orientation and a volume fraction, characterized in that:

• the number of “grain” blocks is less than or equal to ten,
• the number of slip systems is less than or equal to six,
• in addition, the microscopic model optionally uses:
• up to seven “grain boundary” blocks which each have an orientation and a volume fraction and whose deformation is determined on the basis of at least one opening system, the trace of the tensor of the microscopic plastic strains of each “grain boundary” block being positive,
• at most one “hole” block which has a variable volume fraction and whose plastic deformation is purely in volume and whose microscopic plastic strains tensor trace is positive.