S. Onaka et al., EFFECT OF DIFFUSIONAL RELAXATION ON THE SHAPE CHANGE OF LIQUID B2O3 PARTICLES IN A DEFORMING CU MATRIX, Acta metallurgica et materialia, 43(4), 1995, pp. 1577-1585
Citations number
24
Categorie Soggetti
Material Science","Metallurgy & Metallurigical Engineering
Diffusional relaxation around B2O3 particles which occurs concurrently
with the deformation of a surrounding Cu matrix is experimentally and
theoretically analysed from the shape change of the particles. The or
iginally spherical B2O3 particles in the Cu matrix become a liquid at
high temperatures. Although plastic deformation of the Cu matrix induc
es the particle elongation, a relaxation process operates to suppress
the elongation at high temperatures. This causes smaller aspect ratios
of the liquid particles than those expected from applied tensile stra
ins. The relaxation is caused by the diffusion of the matrix Cu atoms
along the Cu-B2O3 interface under the driving force of the excess inte
rface free energy. The activation energy of the interface diffusion is
evaluated as 1.7 eV. The kinetics of the shape change of a liquid par
ticle in a deforming matrix is formulated including the effect of the
diffusional relaxation. The theoretical calculations explain the exper
imental results on the temperature and particle-size dependences of th
e change in the aspect ratio of the B2O3 particles.