The compressive creep behavior of a Pu-1 wt pct Ga δ-stabilized alloy at elevated temperatures

Mechanical properties of delta-stabilized Pu–1.0 wt% Ga alloys

“…This is in good agreement with the value of 36 300 cal/mol for self-diffusion of Pu in a delta alloy [44]. The work of Lytton et al [43] provides further discussion on the unusual primary creep characteristics of delta as well as stress dependence during steady-state creep.…”

“…The study by Lytton et al [43] provides data on constant stress compression creep tests for a high-purity delta alloy over the temperature range from 252 to 382°C for stresses from 4.8 to 17.3 MPa. Although the primary creep behavior could not be correlated by established techniques, the creep rates developed after true strains of about 0.15 provided good agreement with the temperature and stress dependence of creep for pure FCC metals and dilute alloys.…”

“…Elevated temperature creep studies of delta are somewhat limited, however two papers [42,43] delineate the salient features for a nominal-purity alloy and a high-purity alloy, respectively. Robbins and Wheeler [42] discussed the compressive creep characteristics of a nominal-purity delta alloy at a constant stress over a temperature range of 234 to 387°C.…”

“…Consequently, most of the mechanical property information that has been published is for Pu-Ga binary alloys with emphasis on the 1.0 wt% (3.34 at.%) alloy. The largest body of data on this alloy was published in the decade between 1965 and 1975 [5][6][7][8][9]11,12,14,[16][17][18][21][22][23][25][26][27][28][29][30][31][32][33][34][37][38][39][40][41][42][43][44][45][46], with limited studies since that time [10,13,24,35]. Fig.…”

Formation and recovery of irradiation and mechanical damage in stabilized δ-plutonium alloys

“…Based on these estimates, the approximate uniform concentration of these 20Å defects would be 4.4 × 10 19 cm −3 as compared with the He bubble 20Å concentration 1.5 × 10 17 /cm −3 reported by Schwartz et al [24] Therefore, these defects should be approximately 300 times more numerous than He bubbles. Such defect structures are likely to impact phase transformations as witnessed in this thermal expansion study due to associated lattice strain and to alter plastic deformation and mechanical yield as seen in ␦-phase Pu alloys due to dislocation pinning effects [25,26].…”