Amorphization Kinetics of Zr (Cr,Fe)2 Under Ion Irradiation

Amorphization Kinetics of Zr (Cr,Fe)2 Under Ion Irradiation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

Get Book Here

Book Description

Amorphization Kinetics of Zr (Cr,Fe)2 Under Ion Irradiation

Amorphization Kinetics of Zr (Cr,Fe)2 Under Ion Irradiation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

Get Book Here

Book Description


Amorphization Kinetics of Zr(Cr, Fe)2 Under Ion Irradiation

Amorphization Kinetics of Zr(Cr, Fe)2 Under Ion Irradiation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

Get Book Here

Book Description
Thin foils of Zircaloy-4 were irradiated with 350 KeV 4°Ar ions in the dual ion beam/HVEM facility at Argonne National Laboratory at 300--650 K. The irradiation-induced amorphization of the intermetallic precipitates Zr (Cr; Fe)2 and Zr2 (Ni, Fe) was studied in-situ. For Zr (Cr, Fe)2 precipitates the dose-to-amorphization was found to increase exponentially with temperature, with a critical temperature of about 650 K. The amorphization morphology was shown to be homogeneous, with no preferential site for nucleation, in contrast to neutron-irradiation amorphization which started at the precipitate-matrix interface. For Zr2 (Ni, Fe) precipitates it was found that amorphization occurred at 550 and 600 K, whereas in neutron irradiation no amorphization has been observed at those temperatures. The results are discussed in context of previous neutron and electron irradiations and likely amorphization mechanisms are proposed.

Amorphization Kinetics of Zr(Cr, Fe)[sub 2] Under Ion Irradiation

Amorphization Kinetics of Zr(Cr, Fe)[sub 2] Under Ion Irradiation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

Get Book Here

Book Description
Thin foils of Zircaloy-4 were irradiated with 350 KeV [sup 40]Ar ions in the dual ion beam/HVEM facility at Argonne National Laboratory at 300--650 K. The irradiation-induced amorphization of the intermetallic precipitates Zr (Cr; Fe)[sub 2] and Zr[sub 2] (Ni, Fe) was studied in-situ. For Zr (Cr, Fe)[sub 2] precipitates the dose-to-amorphization was found to increase exponentially with temperature, with a critical temperature of about 650 K. The amorphization morphology was shown to be homogeneous, with no preferential site for nucleation, in contrast to neutron-irradiation amorphization which started at the precipitate-matrix interface. For Zr[sub 2] (Ni, Fe) precipitates it was found that amorphization occurred at 550 and 600 K, whereas in neutron irradiation no amorphization has been observed at those temperatures. The results are discussed in context of previous neutron and electron irradiations and likely amorphization mechanisms are proposed.

Amorphization Kinetics of Zr{sub 3}Fe Under Electron Irradiation

Amorphization Kinetics of Zr{sub 3}Fe Under Electron Irradiation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 16

Get Book Here

Book Description
0.9 MeV electron irradiations were performed at 28--220 K in a high-voltage electron microscope (HVEM). By measuring onset, spread and final size of the amorphous region, factoring in the Guassian distribution of the beam, a kinetic description of the amorphization in terms of dose, dose rate and temperature was obtained. The critical temperature for amorphization by electron irradiation was found to be ∼220 K, compared to 570--625 K for 4°Ar ion irradiation. Also, the dose-to-amorphization increased exponentially with temperature. Results indicated that the rate of growth of the amorphous region under the electron beam decreased with increasing temperature and the does-to-amorphization decreased with increasing dose rate. The size of the amorphous region saturated after a region dose, the final size decreasing with increasing temperature, and it was argued that this is related to the existence of a critical dose rate, which increased with temperature, below which no amorphization occurred. The above observations can be understood in the framework of the kinetics of damage accumulation under irradiation.

Amorphization Kinetics of Zr3Fe Under Electron Irradiation

Amorphization Kinetics of Zr3Fe Under Electron Irradiation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 16

Get Book Here

Book Description
0.9 MeV electron irradiations were performed at 28--220 K in a high-voltage electron microscope (HVEM). By measuring onset, spread and final size of the amorphous region, factoring in the Guassian distribution of the beam, a kinetic description of the amorphization in terms of dose, dose rate and temperature was obtained. The critical temperature for amorphization by electron irradiation was found to be (approximately)220 K, compared to 570--625 K for 4°Ar ion irradiation. Also, the dose-to-amorphization increased exponentially with temperature. Results indicated that the rate of growth of the amorphous region under the electron beam decreased with increasing temperature and the does-to-amorphization decreased with increasing dose rate. The size of the amorphous region saturated after a region dose, the final size decreasing with increasing temperature, and it was argued that this is related to the existence of a critical dose rate, which increased with temperature, below which no amorphization occurred. The above observations can be understood in the framework of the kinetics of damage accumulation under irradiation.

Amorphization kinetics of zr3fe under electron irradiation

Amorphization kinetics of zr3fe under electron irradiation PDF Author: A. T. Motta
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

Get Book Here

Book Description


In Situ HVEM Studies of Phase Transformation in Zr Alloys and Compounds Under Irradiation

In Situ HVEM Studies of Phase Transformation in Zr Alloys and Compounds Under Irradiation PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 41

Get Book Here

Book Description


Temperature and Ion-mass Dependence of Amorphization Dose for Ion Beam Irradiated Zircon (ZrSiO[sub 4].

Temperature and Ion-mass Dependence of Amorphization Dose for Ion Beam Irradiated Zircon (ZrSiO[sub 4]. PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

Get Book Here

Book Description
The temperature dependence of amorphization dose for zircon under 1.5 MeV Kr ion irradiation has been investigated using the ANL HVEM-Tandem Facility. Three regimes were observed in the amorphization dose-temperature curve. In the first regime (15 to 300 K), the critical amorphization dose increased from 3.06 to 4.5 ions/nm[sup 2]. In the second regime (300 to 473 K), there is little change in the amorphizationdose. In the third regime (> 473 K), the amorphization dose increased exponentially to 8.3 ions/nm[sup 2] at 913 K. This temperature dependence of amorphization dose can be described by two processes with different activation energies (0.018 and 0.31 eV respectively) which are attributed to close pair recombination in the cascades at low temperatures and radiation-enhanced epitaxial recrystallization at higher temperatures. The upper temperature limit for amorphization of zircon is estimated to be 1100 K. The ion-mass dependence of the amorphization dose (in dpa) has also been discussed in terms of the energy to recoils based on data obtained from He, Ne, Ar, Kr, Xe irradiations and a [sup 238]Pu-doped sample.

Temperature and Ion-mass Dependence of Amorphization Dose for Ion Beam Irradiated Zircon (ZrSiO4).

Temperature and Ion-mass Dependence of Amorphization Dose for Ion Beam Irradiated Zircon (ZrSiO4). PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 7

Get Book Here

Book Description
The temperature dependence of amorphization dose for zircon under 1.5 MeV Kr ion irradiation has been investigated using the ANL HVEM-Tandem Facility. Three regimes were observed in the amorphization dose-temperature curve. In the first regime (15 to 300 K), the critical amorphization dose increased from 3.06 to 4.5 ions/nm2. In the second regime (300 to 473 K), there is little change in the amorphizationdose. In the third regime (> 473 K), the amorphization dose increased exponentially to 8.3 ions/nm2 at 913 K. This temperature dependence of amorphization dose can be described by two processes with different activation energies (0.018 and 0.31 eV respectively) which are attributed to close pair recombination in the cascades at low temperatures and radiation-enhanced epitaxial recrystallization at higher temperatures. The upper temperature limit for amorphization of zircon is estimated to be 1100 K. The ion-mass dependence of the amorphization dose (in dpa) has also been discussed in terms of the energy to recoils based on data obtained from He, Ne, Ar, Kr, Xe irradiations and a 238Pu-doped sample.

Zirconium in the Nuclear Industry

Zirconium in the Nuclear Industry PDF Author: Gerry D. Moan
Publisher: ASTM International
ISBN: 0803128959
Category : Nuclear fuel claddings
Languages : en
Pages : 891

Get Book Here

Book Description
Annotation The 41 papers of this proceedings volume were first presented at the 13th symposium on Zirconium in the Nuclear Industry held in Annecy, France in June of 2001. Many of the papers are devoted to material related issues, corrosion and hydriding behavior, in-reactor studies, and the behavior and properties of Zr alloys used in storing spent fuel. Some papers report on studies of second phase particles, irradiation creep and growth, and material performance during loss of coolant and reactivity initiated accidents. Annotation copyrighted by Book News, Inc., Portland, OR.