must also appear on the (010) face since this face

contains an 024 plane which is also a plane in the 1/5

(042) variant. In a similar way, the 1/5 (402) variant

will appear on the 001 face, but since it is a different

variant of the Dla, its morphology will not be the same as

the Dla morphology of the 1/5 (042). The 1/5 (402)

variant will also appear on the 100 face, since this

variant also contains a 204 plane. To differentiate the

Dla precipitate on the 001 face from the same variants on

the other 100 faces, it is necessary to compare the D022

images with the Dla images. The DO22 images appear only

on the (001) faces of the gamma prime.

 The D022 precipitates form in discreet lines along

(100> directions, analogous to the alignment of the gamma

prime described by Ardell et al. (1966). Figure 5.11a

shows this morphology. The individual morphologies of the

D022 are consistent with the morphologies explained

earlier. The morphology of the Dla phase is also as

predicted from the B = <001> images. The variants of

Ni4Mo Dla, shown in Figures 5.12b and 5.12c, form along

the D022 precipitates, just as they did in the B = <001>

images. These third axis dark field images show that the

interlacing of the Dla and D022 phases results in almost

complete order of the gamma phase.