obviously be in error because of this, not only because

they exclude the quaternary elements, but also because

this exclusion will affect the quantitative total and the

relative amounts of the other elements also. Fortunately,

the concentrations of the quaternary elements in the bulk

alloys are low, 2.0 atomic % for both RSR 197 and 209.

Representative spectra from RSR 209 and RSR 197 gamma and

gamma prime phases are shown in Figures 4.12 a, b, c, and

d. The partitioning of the Ta and W to the gamma and

gamma prime phases is different. Ta partitions almost

exclusively to the gamma prime phase. W appears to be

about equally partitioned between the gamma and gamma

prime phases.

 Interestingly, the nickel content of the gamma and

gamma prime phases was very similar (Table 5.3). This

allowed the Ni-K4'peak to be used as an internal standard

for ratioing against the Mo, Ta, and W lines in order to

measure the partitioning of the Ta or W between the gamma

prime and gamma phases.

 The Ta in the gamma prime cannot exceed about 4

atomic percent. This figure is based on the assumption

that the gamma prime volume fraction is not less than 50%,

a safe underestimate judging from the microstructural

features described in Chapter 5.

 For the same reason, the amount of Ta in the gamma

phase must be less than one percent based on the ratio of

Ta to Ta in the gamma prime and gamma, respectively.