Session 8: Discussion

PAPER 32

C. G. ALLAN UKAEA Dounreay

Was the alpha iron needle-like feature you described a single crystal, i.e. a whisker? Did preferred orientation indicate whether the needle was deposited on the surface or whether it grew from the surface?

A. J. HOOPER

Since X-ray diffration studies of a number of similar, non-adherent, alpha iron needles, occurring in the same region, gave no indica tion of preferred orientation effects it seems unwise to suggest single crystal formation. Neither the needle morphology nor the mode of attachment to the surface gave any indication of the nucleation and growth mechanism.

E. BERKY Westinghouse Research USA