Xavier Averty

Followers

Following

Co-authors

Public Views

Interests

Uploads

Papers by Xavier Averty

The PROMETRA Program: Fuel Cladding Mechanical Behavior under High Strain Rate

Nuclear Technology, 2007

ABSTRACT

Induction Heating on Dynamic Tensile Tests in CEA Saclay

The LCMl (Laboratorv for characterization of irradiated materials), located in CEA from Saclav. i... more The LCMl (Laboratorv for characterization of irradiated materials), located in CEA from Saclav. is in charge oi the mechanical tests on iriaiated materials. The dynamic tensiie testing machine, in a hot celi equipped with two remote handlings. has been first improved in 1995. to fulfiil the French safety programs on Reactivity Initiated Accident C A 0 1 .::U SCI .5 <l :11 S ~ 2 . n rr i to oni.3 11 rwt;ua,~cs cropcn, cnla on r..rrrrl L ,:a", c m " ng $,p4 ' l r U e u l i q . m t t , in,: -;u~ o j s ieapmsc .noer H A or .OCA lrios ert cscnq 3n.1 lnc!rnn coroton; Fc' lnt HIA. 1.1 2 illem, 1 2 i l ?g 1 wdr8 r.,'e, .p 1, 5 i' a m nsal ng rd!es .p !o 210.C S . ;n F 1% _OS? 01 CS dnl ACC odi i s . OCA led g ;: sra r i.?lr, U. 10 an0 n c x r g rales u. ?WC s KO. o oi. a00102r .?h: The tensile samples are machined with a spark erosion machine. directiy from pieces of cladding previously defueied. Two kinds of samples can be machined in the ciadding: Axial sample...

Atomic Energy and Alternative Energies Com… 129 PUBLICATIONS 1,235 CITATIONS SEE PROFILE

All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more

format_quoteCr-enriched b.c.c. α' phase forms under irradiation as low as 250°C; precipitate radii around 1 nm observed.format_quote

Download

Iodine induced stress corrosion cracking and axial creep: 2 new cladding testing facilities at Leci laboratory

Extension and refurbishment of the CEA Saclay Leci hot laboratory initiated 10 years ago is now c... more Extension and refurbishment of the CEA Saclay Leci hot laboratory initiated 10 years ago is now considered as completed. The present paper describes two new cladding testing facilities available at Leci. Iodine induced stress corrosion cracking of zirconium alloys fuel claddings may develop during power transient due to pellet-cladding interaction (PCI). This phenomenon was studied in the previous CEA installation using iodine atmosphere internal pressure creep tests on defuelled samples. The new facility allows tests to be performed in two modes: i) driving on the pressure with the ability to do complex loading creep tests, ii) driving on the hoop strain thanks to the diameter laser measurement, which allows relaxation tests to be achieved and consequently to be more representative of the loading imposed by the pellet on the cladding during PCI. Inert atmosphere can also be used in order to determine mechanical properties of irradiated claddings or hydrides reorientation conditions...

Behavior of Different Austenitic Stainless Steels, Conventional, Reduced Activation (RA) and ODS Chromium-Rich Ferritic-Martensitic Steels Under Neutron Irradiation at 325°C in PWR Environment

Effects of Radiation on Materials: 20th International Symposium

Ductility and Failure Behaviour of both Unirradiated and Irradiated Zircaloy 4 Cladding Using Plane Strain Tensile Specimens

format_quoteIRSN and EDF are conducting PROMETRA to gather vital material properties for Reactivity Initiated Accidents.format_quote

Download

Zircaloy-4 fuel cladding mechanical behavior in the field of RIA transients through the PROMETRA program

Failure of hydrided zircaloy-4 fuel cladding tubes under RIA loading conditions

The anisotropic viscoplastic behavior and the fracture of cold-worked stress relieved Zircaloy-4 ... more The anisotropic viscoplastic behavior and the fracture of cold-worked stress relieved Zircaloy-4 cladding tubes is investigated under reactivity initiated accidents loading conditions. The combined effects of temperature (from 25°C up to 480°C), hydrogen content (from 0 up to 1200 ppm) and stress/stain state (from uniaxial tension up to plane strain tension) are analyzed. A strengthening effect of hydride precipitates and a softening effect of dissolved hydrogen are observed. Ductility of the material increases with increasing temperature and decreases with increasing hydrogen content at room temperature. The embrittlement effect of hydrides is substantially reduced when increasing temperature. A slight effect of stress/strain triaxiality is evidenced. The evolution of material ductility is associated with a change in the macroscopic fracture aspect and the failure mechanisms. A model is proposed to describe the anisotropic viscoplastic behavior of the material.

Download

Mechanical Properties of Zircaloy-4 PWR Fuel Cladding with Burnup 54-64MWd/kgU and Implications for RIA Behavior

Journal of ASTM International, 2005

The PROMETRA material testing program is a support program related to the study of high burnup fu... more The PROMETRA material testing program is a support program related to the study of high burnup fuel rod behavior under Reactivity Initiated Accidents (RIA) and to the interpretation of the CABRI REP-Na RIA test results. Hoop and axial tensile tests have been performed on fresh and irradiated Zircaloy-4 cladding alloy first at CEA Grenoble hot labs and now at CEA Saclay in order to assess the cladding mechanical behavior during RIA transients. Efforts have been continuously carried out in order to improve the prototipicallity of the tests for RIA studies involving new specimens and new testing techniques. The corrosion level of irradiated specimens reached up to 130 μm of oxide layer thickness. The influence of in-pile oxide layer spallation has also been addressed. High strain-rate material properties of irradiated Zircaloy-4 and the consequences of hydride embrittlement can be derived from the PROMETRA program.

The PROMETRA program: a reliable material database for highly irradiated Zircaloy-4, ZirloTM and M5TM fuel claddings

The assessment of the mechanical properties of the highly irradiated fuel claddings during an RIA... more The assessment of the mechanical properties of the highly irradiated fuel claddings during an RIA (Reactivity Initiated Accident) has been carried out in the framework of the PROMETRA programme. Three main types of tests including burst tests, hoop and axial tensile tests, have been performed in CEA-Saclay hot laboratories in order to determine the cladding tensile properties used in the SCANAIR code. The representativeness of each test with regard to the RIA loading conditions can be addressed and analyzed in terms of strain or stress ratio. The present paper reports the high strain rate ductile mechanical properties of irradiated ZIRLO TM and M5 TM alloys derived from the PROMETRA program and their comparison to the stress-relieved irradiated Zircaloy-4. Results of specific analysis of the behaviour of the 6 cycle M5 TM and ZIRLO TM 75 GWd/tM for temperatures higher than 600°C are also presented.

Download

$Research paper thumbnail of Caracterization of He embrittlement of a 9Cr-1Mo steel using local approach of brittle fracture$

Caracterization of He embrittlement of a 9Cr-1Mo steel using local approach of brittle fracture

In order to investigate helium effects on the fracture properties of martensitic mod 9Cr-1Mo stee... more In order to investigate helium effects on the fracture properties of martensitic mod 9Cr-1Mo steel, subsize Charpy specimens were implanted in the notch region at 250°C to 0.125 and 0.25 at% helium, and at 400°C to 0.25 at% helium using a degraded 34 MeV 3 He ion beam and subsequently submitted to static bending tests at room temperature. For the implanted specimens, an unstable crack extension with no macroscopic plasticity was systematically observed during testing : crack initiated in the implanted zones of the samples are arrested in the non affected material. In the implanted zones, the fracture mode is fully brittle with both intergranular and cleavage fracture, whereas in the non affected material, the fracture is ductile. Unimplanted samples were tested at -170°C. In this case, the fracture mode is pure cleavage. Finite element simulations of the tests performed on unimplanted and implanted specimens were carried out to determine stress and strain fields at crack initiation. Based on these computations, we have proposed that the mechanism of brittle fracture is controlled by a double criterion depending on implantation temperature and helium content.

format_quoteFinite Element calculations provide a minimum and maximum fracture stress for helium-implanted samples, supporting experimental data with computational models.format_quote

Download

MECHANICAL CHARACTERISTICS OF 5754-NET-O ALUMINUM ALLOY IRRADIATED UP TO HIGH FLUENCES : NEUTRON SPECTRUM AND TEMPERATURE EFFECTS

The 5000 and 6000 series aluminum alloys are extensively used in research reactors. To validate t... more The 5000 and 6000 series aluminum alloys are extensively used in research reactors. To validate the choice of the suitable Al-alloys for the core components and the experimental devices for the conception of the Jules Horowitz Reactor (RJH), a characterization program of some highly irradiated components was performed. In this paper, we focalise on the 5754- NET alloy in the annealed temper (O treatment) which was irradiated under different neutron spectrum, in Osiris and Orphée reactors. Tensile test results on this alloy irradiated for 30 years in OSIRIS are presented. The temperature and fluence effects are discussed. Tensile test results on the 5754-NET alloy irradiated for 15 years in ORPHEE in a cold neutron flux (cold source shell) are provided and compared with results obtained after irradiation with a harder neutron spectrum in Osiris. Neutron calculations in the ORPHEE cold source shell show that the total flux is hardly reduced by the presence of the cold source, but the ...

format_quoteTotal elongation of 5754-NET-O alloy increases with Si content from neutron flux, while mechanical strength remains mostly unchanged.format_quote

Download

Effect of the bainitic and martensitic microstructures on the hardening and embrittlement under neutron irradiation of a reactor pressure vessel steel

Journal of Nuclear Materials, 2015

ABSTRACT The hardening and the embrittlement under neutron irradiation of an A508 type RPV steel ... more ABSTRACT The hardening and the embrittlement under neutron irradiation of an A508 type RPV steel considering three different microstructures (bainite, bainite-martensite and martensite)have been investigated These microstructures were obtained by quenching after autenitization at 1100°C. The irradiation induced hardening appears to depend on microstructure and is correlated to the yield stress before irradiation. The irradiation induced embrittlement shows a more complex dependence. Martensite bearing microstructures are more sensitive to non hardening embrittlement than pure bainite. This enhanced sensitivity is associated with the development of intergranular brittle facture after irradiation; the pure martensite being more affected than the bainite-martensite. It is of interest to note that this mixed microstructure appears to be more embrittled than the pure bainitic or martensitic phases in terms of temperature transition shift. This behaviour which could emerge from the synergy of the embrittlement mechanisms of the two phases needs further investigations. However, the role of microstructure on brittle intergranular fracture development appears to be qualitatively similar under neutron irradiation and thermal ageing.

Effect of irradiation defects on the work hardening behavior

Scripta Materialia, 2004

Work hardening behavior of irradiated SA 304L and CW 316 austenitic stainless steels is investiga... more

Download

Comparative study on Charpy specimen reconstitution techniques

by B. Bourdiliau and Xavier Averty

Nuclear Engineering and Design, 2011

Reconstitution techniques are often used to allow material from previously fractured Charpy-V spe... more Reconstitution techniques are often used to allow material from previously fractured Charpy-V specimens to be reused for additional experiments. This paper presents a comparative experimental study of various reconstitution techniques and evaluates the feasibility of these methods for future use in shielded cells. The following techniques were investigated: arc stud welding, 6.0 kW CO 2 continuous wave laser welding, 4.5 kW YAG continuous wave laser welding and friction welding. Subsize Charpy specimens were reconstituted using a 400 W YAG pulsed wave laser. The best result was obtained with arc stud welding; the resilience of the reconstituted specimens and the load-displacement curves agreed well with the reference specimens, and the temperature elevation caused by the welding process was limited to the vicinity of the weld. Good results were also obtained with friction welding; this process led to the best quality welds. Laser welding seems to have affected the central part of the specimens, thus leading to different resilience values and load-displacement curves.

Download

Failure of hydrided Zircaloy-4 fuel claddings under RIA loading conditions

Zircaloy-4 fuel cladding mechanical behavior in the field of RIA transients through the PROMETRA program

by Jean Des, Xavier Averty, and P. Yvon

The PROMETRA program: a reliable material database for highly irradiated Zircaloy-4, ZirloTM and M5TM fuel claddings

by Jean Des, Xavier Averty, and P. Yvon

Download

High Temperature Expansion Due to Compression Test for the Determination of a Cladding Material Failure Criterion under RIA Loading Conditions

This paper is mainly dedicated to the development of an out-of-pile test reproducing the thermo-m... more This paper is mainly dedicated to the development of an out-of-pile test reproducing the thermo-mechanical loading conditions encountered during the first stage of a Reactivity Initiated Accidents (RIA) transient, dominated by Pellet Clad Mechanical Interaction (PCMI). In particular, the strain-controlled clad loading under high strain rate associated with temperatures up to 600 deg. C expected during the PCMI phase is simulated by an Expansion Due to Compression (EDC) test achievable at high temperature. The use of appropriate materials for the inner pellet made it possible to achieve the tests from 20 deg. C up to 900 deg. C. The interpretation of the test data is supported by Finite Element Analysis (FEA) including parameters tuned using an inverse method coupling FEA and tests results. A deformation model, identified upon the PROMETRA (Transient Mechanical Properties) experimental database and describing the anisotropic viscoplastic behavior of Cold-Worked Stress Relieved Zircal...

Download

Post-Irradiation Tensile Behavior and Residual Activity of Several Ferritic/Martensitic and Austenitic Steels Irradiated in Osiris Reactor at 325°C up to 9 dpa

Journal of ASTM International, 2005

Download

Xavier Averty

Uploads

Papers by Xavier Averty

Log In