Irradiation Hardening Behavior of He-Irradiated V–Cr–Ti Alloys with Low Ti Addition

A set of V–(4–8)Cr–(0–4)Ti alloys was fabricated to survey an optimum composition to reduce the radioactivity of V–Cr–Ti alloys. These alloys were subjected to nano-indenter tests before and after 2-MeV He-ion irradiation at 500 °C and 700 °C with 0.5 dpa at peak damage to investigate the effect of Cr and Ti addition and gas impurities for irradiation hardening behavior in V–Cr–Ti alloys. Cr and Ti addition to V–Cr–Ti alloys for solid–solution hardening remains small in the unirradiated V–(4–8)Cr–(0–4)Ti alloys. Irradiation hardening occurred for all V–Cr–Ti alloys. The V–4Cr–1Ti alloy shows the highest irradiation hardening among all V–Cr–Ti alloys and the gas impurity was enhanced to increase the irradiation hardening. These results may arise from the formation of Ti(CON) precipitate that was produced by He-ion irradiation. Irradiation hardening of V–Cr–1Ti did not depend significantly on Cr addition. Consequently, for irradiation hardening and void-swelling suppression, the optimum composition of V–Cr–Ti alloys for structural materials of fusion reactor engineering is proposed to be a highly purified V–(6–8)Cr–2Ti alloy.

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Correlation between Microstructural Change and Irradiation Hardening Behavior of He-Irradiated V–Cr–Ti Alloys with Low Ti Addition

Quantum Beam Science ◽

10.3390/qubs5030026 ◽

2021 ◽

Vol 5 (3) ◽

pp. 26

Author(s):

Ken-ichi Fukumoto ◽

Shuichiro Miura ◽

Yoshiki Kitamura ◽

Ryoya Ishigami ◽

Takuya Nagasaka

Keyword(s):

Microstructural Evolution ◽

Atom Probe ◽

Vanadium Alloys ◽

Irradiation Hardening ◽

Fusion Neutron ◽

Hardening Behavior ◽

Ti Alloys ◽

Transmission Electron ◽

Hardening Theory ◽

Ti Addition

V–4Cr–xTi (x = 0 to 4) alloys were used to investigate the additional effect of Cr, Ti and interstitial impurities on the microstructural evolution in He-irradiated V–Cr–Ti alloys to minimize radioactivity after fusion neutron irradiation. Transmission electron microscopy and atom probe tomography were carried out to the He-irradiated specimens at 500 °C with 0.5 dpa at peak damage. A flash electro-polishing method for the FIB-extracted specimen was established for the ion-irradiated vanadium alloys. The microstructural evolution of the irradiation-induced titanium-oxycarbonitride, Ti(CON) precipitates was observed and was influenced by the effect of Ti addition on the Ti(CON) precipitation. Apparent Ti(CON) precipitates formed in V-4Cr-xTi with 2% addition of Ti. In the V-4Cr-1Ti alloy, a high density Ti enriched cluster was formed. The origin of the irradiation hardening increase resulted from the size distribution of Ti(CON) precipitation from the dispersed barrier-hardening theory.

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Nanoindentation Study on the Creep Characteristics and Hardness of Ion-Irradiated Alloys

Materials ◽

10.3390/ma13143132 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3132

Author(s):

Zhenbo Zhu ◽

Hefei Huang ◽

Jizhao Liu ◽

Linfeng Ye ◽

Zhiyong Zhu

Keyword(s):

Room Temperature ◽

Ion Irradiation ◽

Heavy Ion ◽

Irradiation Damage ◽

Alloy 800H ◽

Irradiation Hardening ◽

Damage Resistance ◽

Heavy Ion Irradiation ◽

Creep Characteristics ◽

Before And After

The Hastelloy N alloy, Alloy 800H and 316H stainless steel were irradiated by Xe20+ ion irradiation with energy of 4 MeV at room temperature (peak damage ranging from 0.5 to 10 dpa). The micromechanical properties, hardness and creep plasticity, of these three investigated alloys were characterized before and after irradiation using nanoindentation. The results show that the hardness increases, and creep plasticity degrades with increasing ion dose in all the samples. In comparison, Hastelloy N has good irradiation damage resistance, while that of the 800H and 316H alloys is slightly worse. Additionally, the approximate positive relationship between irradiation hardening and creep plasticity degradation means that the property of creep plasticity of irradiated materials can be reflected from the nanohardness measurement for the heavy ion irradiation cases.

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Effect of Ti addition on microstructural evolution of V–Cr–Ti alloys to balance irradiation hardening with swelling suppression

Nuclear Materials and Energy ◽

10.1016/j.nme.2018.03.008 ◽

2018 ◽

Vol 15 ◽

pp. 122-127 ◽

Cited By ~ 2

Author(s):

K. Fukumoto ◽

K. Tone ◽

T. Onitsuka ◽

T. Ishigami

Keyword(s):

Microstructural Evolution ◽

Irradiation Hardening ◽

Ti Alloys ◽

Ti Addition

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Microstructure and magnetic properties of Nd-Fe-B-(Re, Ti) alloys

Nukleonika ◽

10.1515/nuka-2015-0008 ◽

2015 ◽

Vol 60 (1) ◽

pp. 29-33

Author(s):

Mariusz Hasiak

Keyword(s):

Magnetic Properties ◽

Phase Composition ◽

Volume Fraction ◽

Magnetic Characteristics ◽

Ti Alloys ◽

Wide Range ◽

Magnetically Hard ◽

Ti Addition ◽

Microstructure And Magnetic Properties

Abstract The microstructure and magnetic properties of nanocomposite hard magnetic Nd-Fe-B-(Re, Ti) materials with different Nd and Fe contents are studied. The role of Re and Ti addition in phase composition and volume fraction of the Nd-Fe-B phase is determined. All samples are annealed at the same temperature of 993 K for 10 min. Mössbauer spectroscopy shows that the addition of 4 at.% of Re to the Nd8Fe78B14 alloy leads to creation of an ineligible amount of the magnetically hard Nd2Fe14B phase. Moreover, the microstructure and magnetic characteristics recorded in a wide range of temperatures for the Nd8Fe79−xB13Mx (x = 4; M = Re or Ti) alloys are also analyzed.

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