Effect of hydriding on the creep behavior of HANA-4 zirconium alloy

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:767

Article

Kombaiah, Boopathy^1,2  Sarkar, Apu^1,3  Murty, Korukonda Linga¹ 

[1] North Carolina State Univ, Raleigh, NC 27965 USA

[2] Idaho Natl Lab, Idaho Falls, ID 83401 USA

[3] Bhabha Atom Res Ctr, Mumbai 400085, Maharashtra, India

关键词: Creep;    Zirconium;    Hydrogen;    X-Ray diffraction;    Mechanical Properties;    Process;   

DOI  :  10.1016/j.msea.2019.138435

来源: Elsevier

【 摘 要 】

HANA-4 (High Temperature Alloys for Nuclear Applications) is Zr-1.5 Nb alloy developed by the Korea Atomic Energy Research Institute for advanced nuclear fuel cladding applications. In this work, the effect of hydriding on the biaxial creep behavior of HANA-4 alloy was studied through internal pressurization of closed end tubes by applying a range of hoop stresses (27 MPa-156 MPa) at two temperatures: 400 degrees C and 500 degrees C. Test specimens included two HANA-4 tubes hydrided using an electrolytic method with 387 ppm and 715 ppm of hydrogen, respectively, and non-hydrided HANA-4 tubes as the control sample. To understand the effect of hydriding on creep, steady state creep rates and stress exponents of the specimens were determined from the creep data. Furthermore, in situ X-ray diffraction (XRD) experiments were conducted on the hydrided HANA-4 specimens during heating to detect the dissolution limit of the hydride phase. On examining the results of the creep tests and the XRD experiments collectively, it is concluded that hydrogen while being fully dissolved into the solid solution enhances the creep rate of HANA-4 tubes. On the other hand, hydrogen present, even partially, as hydride phase at the creep test temperature lowers the creep rate. The rate controlling mechanisms of creep in HANA-4, however, remained unchanged as noted from similar stress exponents of the hydrided and non-hydrided specimens. The rationale behind these observations is explained based up on models predicting the interaction of dislocations with hydrogen and hydride phase.

【 授权许可】

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