Page 65 - Handbook of Materials Failure Analysis
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2 Case Studies 59
FIGURE 3.10
Ferrite and coalescence of alloy carbides alongwith isolated creep cavities.
FIGURE 3.11
Ferrite and alloy carbide at the grain boundaries alongwith isolated creep cavities.
2.1.1.6 Discussion
The visual examination of the tube revealed that the tube had failed by a typical nar-
row open burst and the failed zone was accompanied by noticeable swelling of the
tube circumference (Figure 3.7.). This indicates that the tube had suffered from
noticeable creep deformation. Dimensional measurement of the tube revealed appre-
ciable bulging/swelling and reduction in wall thickness at and adjacent to location of
failure. A thick and tightly adherent scale on the internal surface over the length of
