CHAPTER 5
 RESULTS


 5.1 Microstructural Characterization


5.1.1 As Extruded RSR 197 and RSR 209 Alloys


 Figure 5.1 is a low magnification TEM micrograph of a

typical as extruded microstructure. The alloy is RSR

209. The large grains are gamma prime grains that have

precipitated during the extrusion process. The other

areas of the microstructure consist of small cubes of

gamma prime that have precipitated from the gamma solid

solution during the cool down after extrusion. Details of

the optical microstructure can be found in the relevant

Pratt and Whitney quarterly reports (Cox and et al.,

1978). Other phases were present but were not analyzed.

It is probable that they are Mo.

5.1.2 RSR 197 -- As Solution Heat Treated and Quenched


 Figure 5.2a shows the general microstructural

features of this as quenched alloy. This is basically the

starting structure and starting phase distribution for all

subsequent aging practices of RSR 197. There are no

remnants of the primary gamma prime phase that had