Deformation Behavior of Duplex Zircaloy-4-Oxygen Alloys

Mechanical Behavior at High Temperatures of Highly Oxygen- or Hydrogen-Enriched α and Prior-β Phases of Zirconium Alloys

“…A good knowledge of the mechanical properties of this phase at HT is thus an important issue. However, most of open literature data were obtained for oxygen contents lower than 2 wt.% [7][8] [9][10] [11] [12] [13] or did not concern the viscoplastic behavior at HT [7] [14]. There seems to be no data about the creep behavior of the αZr(O) phase for oxygen contents higher than 2 wt.%.…”

Creep flow and fracture behavior of the oxygen-enriched alpha phase in zirconium alloys

“…All literature data come from tests at high stresses , so that previously identified value of n 5 was used for stress normalization. All data were obtained at 800°C with the exception of data from Tseng and Tangri [8] obtained at 850°C and the creep results on Zr-1%Nb-3.2%O obtained at 1000°C in the present study. For both of them, a temperature correction was applied using the activation energy Q of the higher stress regime, given in Table 1.…”

“…The difference between model predictions and experimental results is within the experimental scatter. In order to investigate the strengthening effect of oxygen in more detail, literature data from tensile creep tests [10,11,13] and compression tests [8,9] were put together with the present results on Zr-1%Nb-2/3.2%O in Figure 3. The large scatter in activation energy and stress exponent reported for oxygen-enriched as well as for un-enriched Zr alloys does not allow the investigation of any effect of oxygen on these parameters.…”

“…% are ductile at high temperature (above 800-1000°C) but those with higher oxygen contents are brittle. On the one hand, Tseng and Tangri [8] already obtained strains higher than 8% in compression tests between 850 and 1100°C on 1.8 wt. % oxygen-enriched alpha phase, even though compression tests are less challenging than tensile tests regarding fracture.…”

“…The oxygen-enriched α phase of Zr alloys, called α(O), is also brittle at room temperature from 0.5 wt.% oxygen [6]. The high-temperature mechanical behavior of oxygen-enriched Zr alloys has been reported from compression tests and tensile creep tests [7][8][9]. A significant increase in the compressive steady-state flow stress with increasing oxygen content has been reported, in a linear [7] or an exponential manner [9], for test temperatures between 750°C and 1200°C and for amounts of oxygen up to 2 wt.%.…”