Both Kayla Yano and Keyou Mao have successfully passed the Materials Science & Engineering Ph.D. Qualifying Examination, and are now officially Ph.D. candidates! Congratulations, Kayla and Keyou!
The group presented two talks at the Materials Research Society (MRS) Fall 2017 Meeting in Boston, MA. Our invited talk presented our atom probe tomography results and rate theory model for irradiation evolution of embedded nanoclusters in ferritic/martensitic and oxide dispersion strengthened alloys. The other talk presented our collaboration with the Purdue Network for Computational Nanotechnology to provide summer research experiences for community college students. The full citations for the talks are:
- J.P. Wharry and M.J. Swenson. Rate theory model for irradiation evolution of nanoclusters. Materials Research Society Fall Meeting, Boston MA, November 2017.
- J.P. Wharry, T.A. Faltens, J. Ashcroft, and M. Gonzalez. Summer research experiences in materials & computational nanotechnology for community college students. Materials Research Society Fall Meeting, Boston MA, November 2017.
Thank you to the symposium organizers for inviting us!
The group’s review article, entitled “A review of the irradiation evolution of dispersed oxide nanoparticles in the b.c.c. Fe-Cr system: Current understanding and future directions“, has earned the top spot in the PlumX Metrics Top Ten amongst 2017 Journal of Nuclear Materials articles for social media engagement!
The full citation is:
J.P. Wharry, M.J. Swenson, and K.H. Yano. A review of the irradiation evolution of dispersed oxide nanoparticles in the b.c.c. Fe-Cr system: Current understanding and future directions. Journal of Nuclear Materials 486 (2017) 11-20.
Recent Ph.D. alumni Matthew Swenson published some of the results from his doctoral research in the Journal of Nuclear Materials. The article summarizes the irradiation-induced oxide nanocluster evolution in a model Fe-9%Cr oxide dispersion strengthened (ODS) steel, as well as the G-phase (Si, Ni, Mn-rich phase) nanocluster evolution in the HT9 and HCM12A commercial ferritic/martensitic (F/M) alloys. The article presents atom probe tomographic (APT) results, and studies these results in the context of previous APT investigations of the same alloy heats. Collectively, studying the results in this broader context enable us to draw conclusions about the separate influences of irradiation dose rate and particle type on the nanocluster evolution. The paper concludes by suggesting that a negative temperature shift may be necessary in order for higher dose rate irradiations to properly emulate the nanocluster evolution from lower dose rate irradiations. Congratulations on publishing this work, Matthew!
The full citation is:
M.J. Swenson and J.P. Wharry. Nanocluster irradiation evolution in Fe-9%Cr ODS and ferritic-martensitic alloys. Journal of Nuclear Materials 496 (2017) 24-40. doi: 10.1016/j.jnucmat.2017.08.045
Janelle Wharry recently presented seminars at the School of Materials Engineering at Purdue University and at Oak Ridge National Laboratory. The Purdue MSE seminar focused on the group’s development of TEM in situ mechanical testing techniques for irradiated materials, led by students Kayla Yano and Priyam Patki. The ORNL seminar focused on the irradiation evolution of nanoclusters in oxide dispersion strengthened (ODS) and ferritic/martensitic (F/M) steels. Janelle presented the group’s experimental results obtained by atom probe tomography, and the subsequent predictive capabilities developed by Matthew Swenson and coded by Didier Ishimwe.
The ORNL seminar was part of the ORAU Travel Grant program. Thank you to Dr. Kevin Field for hosting!
Kayla Yano presented an invited seminar at Oak Ridge National Laboratory (ORNL). Her seminar was entitled In Situ TEM & Fe-9%Cr ODS, and focused on exploring a wide variety of transmission electron microscopic (TEM) in situ mechanical testing configurations, specifically as applied to an Fe-9%Cr oxide dispersion strengthened (ODS) alloy.
Kayla received the invitation to this seminar, along with research meetings and tours of ORNL, as part of her American Nuclear Society best poster award. Congratulations again, Kayla!
Ph.D. student Keyou Mao presented his research on microstructural and micromechanical characterization of a 304 stainless steel laser weldment at the Microscopy & Microanalysis 2017 Meeting in St. Louis, Missouri. Janelle Wharry also presented an invited talk overviewing in situ TEM fracture testing of irradiated materials. Thank you, Dr. Sanjit Bhowmick (Bruker), for the invitation!
Conference proceedings are archived as follows:
- K. Mao, Y.Q. Wu, and J.P. Wharry. EBSD and TEM analysis of the heat affected zone of laser welded AISI 304/308 stainless steel. Microscopy & Microanalysis, 23.S1 (2017) 2212.
- J.P. Wharry and K.H. Yano. In situ TEM fracture testing for shallow ion irradiated layers. Microscopy & Microanalysis, 23.S1 (2017) 738.
Janelle Wharry has received a travel grant from Oak Ridge Associated Universities, to support student training and development of collaborations with researchers at Oak Ridge National Laboratory. She will use the grant to share our recent research results, visit the LAMBDA facility, and strengthen relationships for future collaborative proposals.
Our undergraduate summer researchers have come to the end of a productive summer research experience. They had the opportunity to showcase their research outcomes at two different undergraduate research symposia on campus. Esteban Bautista and Didier Ishimwe presented their posters at the Network for Computational Nanotechnology Undergraduate Research Symposium. Didier presented his poster again, and Alex Bullens presented his poster, at the College of Engineering Summer Undergraduate Research Fellowship (SURF) Symposium.
The citations are:
- D. Ishimwe, M. Swenson, J.P. Wharry. Irradiation-induced nanocluster evolution. Purdue University Network for Computational Nanotechnology (NCN) Summer Undergraduate Research Fellowship (SURF) Symposium, West Lafayette IN, 2017.
- E. Bautista, A. Bullens, J.P. Wharry. Understanding the role of fabrication method on metal alloys used in nuclear power plants. Purdue University Network for Computational Nanotechnology (NCN) Summer Undergraduate Research Fellowship (SURF) Symposium, West Lafayette IN, 2017.
- A. Bullens, E. Bautista, K. Mao, J.P. Wharry. Comparison of PM-HIP to cast Alloy 625 for nuclear applications. Purdue University College of Engineering Summer Undergraduate Research Fellowship (SURF) Symposium, West Lafayette IN, 2017.