Prakt. Met. Sonderband 38 (2006) 145 
HT-9 
ilar to the This material shows a thicker oxide layer than T91. It seems that this material has a slightly 
and these higher oxide layer growth rate especially in the beginning of the experiment. The same 
EM, WDX analysis is performed as for T91. Figure 3 shows the SEM, WDX and nano indentation 
> layers is results. The inner layer looks rougher in cross section than the outer layer. In Figure 3a, the 
5 than the nano indents performed on this material can be seen. The WDX measurements (Figure 3b) 
tion of the show an outer oxide layer, inner oxide layer, transition zone and bulk metal. Again the outer 
ntified as layer is oxygen and chromium rich while the inner oxide layer is iron rich. A slight silicon and 
er has the chromium enrichment between these two zones is found. The nano indentation shows that 
has less the E-modulus of the steel is the highest decreases in the oxide layers. The hardness 
ht silicon increases throughout the layer but the value is not as high as expected for an iron or 
tion. Until chromium oxide. 
1 radiation 
1e on this (Chso r 
hardness = 3 
© 200 
150 : 
0 
' 100 
4 0 | Epoxvilt + 
| Position 
©) N | | 
A e— Gum 28 2a Silicon —%— Chromium —@— Bismuth 
aa Oxide idvers rpnsition Bulk + Oxygen —#— Iron Lead 
2 80000 + . . 
c Figure 3. (a) The SEM image and 
2 60000 - (b) the corresponding WDX line 
40000 - scan of the HT-9 material after 600h 
Ls exposure in LBE. The nano indents 
Kom io veers are visible in the SEM image. (c) 
Je re =r >» Hardness and E-modulus. 
Depth [um] 
EP823 
EP 823 shows a different behavior than that of T91 and HT-9. It can be seen in Figure 4a that 
the outer oxide layer is dense and homogeneous while the inner oxide layer is not continuous 
throughout the surface. The inner layer appears more like localized oxidation but a correlation 
to the grain structure is not found. The WDX measurement shows no drop in iron 
concentration between the inner layer and outer layer as in HT-9 and T91. Silicon is enriched 
in both oxide layers as well as chromium and oxygen. The trend in the nano indentation 
results are similar to those observed for T91. The E-modulus decreases in the layers while