oan Taking into account the heterogeneity of the specimen it cannot be 
ERAT said with certainty that in the as-forged condition there was an 
Ss increase in the austenite content (+0.36%) after ageing, as no 
ln, statistical study was done through several determinations of the 
E austenite content before nor after ageing. 
a Austenite content found by the metallographic method was very close 
tag to that determined by X-ray diffractometry. However, as only the 
white regions resolved with 200x magnification were counted, the 
result 0.99% is underestimated. Thus, the volumetric fraction of 
le "white constituents" should be higher than the volumetric fraction 
TEs determined through X-ray diffractometry. This reinforces the 
), 38 shown suspicion that the "white constituents" are not only austenite. 
The results of the microsegregation degree evaluation of nickel, 
a molybdenum and titanium by the electron microprobe are condensed in 
LL Table II. 
CL __ ___ Homogenization time at 1197°5 Th) 1 
0 0 (As-forged)l 1.5 | 10 | 25 | 35 | s0 
_ Ni 7960 8210 8120 8190 8220 8232 1 
Dan I | Mo 254 
Hm Ti 91.5 94.7 88.6 94.1 | 86.2 89.0 
| Ni 270 1 221 17.8 101 95 82 
S 27.2 22.1 8.6 7.0 
Ti | 19.4 17.4 | 8.2 | 4.9 39 4.2 
oy LN 3.4 1.2 1.0 
(%) 10.9 2.8 
Ti 21.2 18.4 9.2 4.8 4,5 4.7 
oo _ Ni | 8496 8554 8458 8451 8454 8397 
able 1, I 17 Mo 307 273 
sy "TH 137 79 
Ni | 6689 7045 7573 7916 7956 8039 
I 233 | 
f the " TTI 56 I 6 85 | 76 | 80 _ 
Ni 1.27 1.07 1.04 
[14/1 1.57 1.50 
FREE 2.45 2.08 1.54 1.24 1.27 1.24 
I=average of 100 X-ray intensities, S=standard deviation of a sample, 
CV=coefficient of variation, Iy~maximum value of X-ray intensity, I =minimum 
value of X-ray intensity, I/1 =quotient that reflects the segregation ratio 
TABLE II - Electron microprobe results. 
The results of Iw In and CV for the as-forged condition show that the 
most segregated element is titanium followed by molybdenum and nickel, 
a in accordance with Reference 8. The diagrams shown in Figures 13, 14 
and 15 show the segregation profilesofnickel, molybdenum and titanium 
Prakt. Met. Sonderbd. 21 (1990) 
147