Density Changes in Plutonium Observed from Accelerated Aging using Pu-238 Enrichment

Chung, B W; Thompson, Stephen R.; Woods, C H; Hopkins, David; Gourdin, William H.; Ebbinghaus, B B

doi:10.1557/proc-802-dd1.10

Cited by 7 publications

(10 citation statements)

References 2 publications

(8 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…% Ga. Details of experiments are presented elsewhere 1 . Two different lengths of 238 Pu-enriched alloy specimens (3 cm and 2 cm) are used to differentiate between surface oxidation and volumetric swelling in the materials.…”

Section: /12mentioning

confidence: 99%

See 1 more Smart Citation

Analysis of density changes in plutonium observed from accelerated aging using Pu-238 enrichment

Chung

Saw

Thompson

et al. 2007

Journal of Alloys and Compounds

View full text Add to dashboard Cite

(ReceivedWe present dimensional and density changes in an aging plutonium alloy enriched with 7.3 at. % of 238 Pu and reference alloys of various ages. After 45 equivalent years of aging, the enriched alloys at 35°C have swelled in volume by 0.14 to 0.16 % and now exhibit a near linear volume increase, without void swelling. Based on X-ray diffraction measurements, the lattice expansion by self-irradiation appears to be the primary cause for dimensional changes during the initial 2-3 years of aging. Following the initial transient, the density change is primarily cause by a constant helium in-growth rate as a result of α-particle decay.

show abstract

Section: /12mentioning

confidence: 99%

“…Previously, we reported the observation of density and volume changes due to selfirradiation in enriched alloys 1 . In this paper, it will shown that the decrease in density is a result of the expansion in Pu lattice, which saturates within approximately three years of natural aging, and the continued build-up of helium in-growth.…”

Section: Introductionmentioning

confidence: 98%

Analysis of density changes in plutonium observed from accelerated aging using Pu-238 enrichment

Chung

Saw

Thompson

et al. 2007

Journal of Alloys and Compounds

View full text Add to dashboard Cite

show abstract

“…Changes in quasi-static density and mechanical properties at ambient temperature and pressure are expected due to the aging process. Our past results have shown gradual increase in strength, decrease in density and ductility of plutonium alloys due to aging [3][4][5]. In this paper we update changes in density and mechanical properties of plutonium alloys due to aging.…”

Section: Introductionmentioning

confidence: 80%

“…The schematic and detailed operations of the dilatometer system are presented elsewhere [3][4][5], so only a brief description is provided here. An LVDT measures minute changes, 0.1 micron or less, in the position of a push-rod by monitoring changes in the inductance of a detector coil.…”

Section: Methodsmentioning

confidence: 99%

Physical Property Changes in Aging Plutonium Alloys

2008

View full text Add to dashboard Cite

Plutonium, because of its self-irradiation by alpha decay, ages by means of lattice damage and helium in-growth. These integrated aging effects will result in microstructural and physical property changes. Because these effects would normally require decades to measure, studies are underway to asses the effects of extended aging on the physical properties of plutonium alloys by incorporating roughly 7.5 wt% of highly specific activity isotope 238 Pu into the weapons-grade plutonium to accelerate the aging process. This paper presents updated results of self-irradiation effects on enriched and reference alloys measured from the immersion density, dilatometry, and mechanical tests. After nearly 90 equivalent years of aging, both the immersion density and dilatometry show that the enriched alloys at 35°C have decreased in density by ~0.19 % and now exhibit a near linear density decrease, without void swelling. Both tensile and compression measurements show that the aging process continues to increase the strength of plutonium alloys.

show abstract

“…If part of the d-phase were to transform to a different phase, most likely to the a-phase, a volume contraction would occur. Long-term experimental studies are in progress to detect and measure precisely the sum of all possible dimensional changes, and some data have recently been published on a plutonium-gallium alloy enriched with the isotope 238 Pu [4]. Theoretical studies, however, must be carried out to quantify the different contributions.…”

Section: Introductionmentioning

confidence: 99%