Radiation Damage Studies on Titanium Alloys as High Intensity Proton Accelerator Beam Window Materials

Conference · Thu Feb 06 00:00:00 EST 2020

DOI:https://doi.org/10.7566/JPSCP.28.041001· OSTI ID:1989317

Ishida, Taku ^[1]; Wakai, Eiichi ^[2]; Makimura, Shunsuke ^[2]; Hurh, Patrick ^[3]; Ammigan, Kavin ^[3]; Casella, Andrew M.  ^[4]; Edwards, Danny J. ^[4]; Senor, David J. ^[4]; Densham, Chris J. ^[2]; Fitton, Michael ^[5]; Bennett, Joe M. ^[6]; Kim, Dohyun ^[7]; Simos, N ^[7]; Calviani, Marco ^[2]; Torregrosa Martin, Claudio ^[8]

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1. J-PARC
2. VISITORS
3. Fermi National Accelerator Laboratory
4. BATTELLE (PACIFIC NW LAB)
5. STFC Rutherford Appleton Laboratory
6. Science and Technology Facilities Council, Rutherford Appleton Laboratory
7. Brookhaven National Laboratory
8. European Center for Nuclear Research (CERN)

A high-strength dual a+ß phase titanium alloy Ti–6Al–4V is utilized as a material for beam windows in several accelerator target facilities. However, relatively little is known about how material properties of this alloy are affected by high-intensity proton beam irradiation. With plans to upgrade neutrino facilities at J-PARC and Fermilab to over 1 MW beam power, the radiation damage in the window material will reach a few displacements per atom (dpa) per year, significantly above the ~0.3 dpa level of existing data. The international RaDIATE collaboration, Radiation Damage In Accelerator Target Environments, has conducted a high intensity proton beam irradiation of various target and window material specimens at Brookhaven Linac Isotope Producer (BLIP) facility, including a variety of titanium alloys. Post-Irradiation Examination (PIE) of the specimens in the 1st capsule, irradiated at up to 0.25 dpa, is in progress. Tensile tests in a hot cell at Pacific Northwest National Laboratory (PNNL) exhibited a clear signature of radiation hardening and loss of ductility for Ti–6Al–4V, while Ti–3Al–2.5V, with less ß phase, exhibited less severe hardening. Microstructural investigations will follow to study the cause of the difference in tensile behavior between these alloys. High-cycle fatigue (HCF) performance is critical to the lifetime estimation of beam windows exposed to a periodic thermal stress from a pulsed proton beam. The first HCF data on irradiated titanium alloys are to be obtained by a conventional bend fatigue test at Fermilab and by an ultrasonic mesoscale fatigue test at Culham Laboratory. Specimens in the 2nd capsule, irradiated at up to ~1 dpa, cover typical titanium alloy grades, including possible radiation-resistant candidates. These systematic studies on the effects of radiation damage of titanium alloy materials are intended to enable us not only to predict realistic lifetimes of current beam windows made of Ti–6Al–4V, but also to extend the lifetime by choosing a more radiation and thermal shock tolerant alloy with a preferable heat treatment, or even by developing new materials.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1989317
• Report Number(s): PNNL-SA-167289
• Resource Relation: Conference: Proceedings of the 14th International Workshop on Spallation Materials Technology, November 11-16, 2018, Fukushima, Japan. JPS Conference Proceedings
• Country of Publication: Japan
• Language: English

Related Subjects

Titanium Alloy
Beam Window
Proton Beam
Radiation damage