N. Yamamoto et al., MICROSTRUCTURAL OBSERVATION OF HELIUM IMPLANTED AND CREEP RUPTURED FE-25-PERCENT-NI-15-PERCENT-CR ALLOYS CONTAINING VARIOUS MC AND MN FORMERS, Journal of nuclear materials, 263, 1998, pp. 1628-1633
Citations number
12
Categorie Soggetti
Nuclear Sciences & Tecnology","Mining & Mineral Processing","Material Science
Transmission electron microscopic observations have been carried out o
n Fe-25%Ni-15%Cr austenitic alloys with various MX (M = V, Ti, Nb, Zr;
X = C, N) stabilizers after helium implantation and creep rupture at
923 K. It is shown that suppression of helium embrittlement can be ach
ieved through a higher dispersion density of incoherent precipitates b
ecause of their high capability of bubble entrapment. A good agreement
between the average distance of grain boundary bubbles exceeding the
minimum critical size and the spacing of cavity traces on intergranula
rly fractured surfaces is obtained. This suggests that the enhancement
of grain boundary decohesion by helium is a result of unstable growth
of super-critical helium bubbles. (C) 1998 Elsevier Science B.V. All
rights reserved.