Constrained Cavity Growth, Its Use in Quantifying Recent Creep Fracture Results

摘要: Abstract Growth of grain boundary cavities by stress directed vacancy absorption is normally assumed to be controlled microstructure insensitive diffusion processes. However, under certain conditions, cavity growth may become much slower than predicted control, due constraints imposed the or an inhomogeneous distribution cavities. Three possible constraining micromechanisms are examined and lower bounds rate calculated which, in each case, result rates being proportional deformation rate, thus sensitive microstructure, also square spacing. Direct evidence supporting concept constrained presented analysing some published data. It shown that apparently conflicting results three recently investigations into creep fracture can reconciled quantitatively predicting transition between controlled...