Steve Johns, graduate student in the Micron School of Materials Science and Engineering has recently received a first place – best poster award, and a cash prize at the 5th biennial Nuclear Materials Conference (NuMat 2018) in Seattle. Research presented, titled Microstructural Response of Nuclear Graphite During In-situ Heating and Electron Irradiation, reports the discovery of new mechanisms responsible for irradiation induced dimensional changes in graphite at higher temperatures via the formation of fullerenes and other carbon nanoforms. This work has also been accepted for publication in the journal CARBON.
Working with Dr. Rick Ubic in the Functional Ceramics Research Group and Dr. Karthik Chinnathambi at the Boise State Center for Materials Characterization (BSCMC), Steve has had great opportunities to conduct specialized research and work with a team of colleagues on several important initiatives. In fact, Steve has already published a research paper entitled “A new oxidation based technique for artifact free TEM specimen preparation of nuclear graphite” [S. Johns, W. Shin, J.J. Kane, W.E. Windes, R. Ubic, C. Karthik, A new oxidation based technique for artifact free TEM specimen preparation of nuclear graphite, J. Nucl. Mater. 505 (2018) 62–68, doi:10.1016/j.jnucmat.2018.03.058.] as the first author in the Journal of Nuclear Materials.
Impressed with Steve’s accomplishments, we asked him to tell us about his path to success. Steve already had a career as a successful residential and commercial construction worker before he enrolled in the Ph.D. Program. He worked his way up to lead foreman and held that position for six years. Even so, he recognized that this type of work would continue to provide a harsh and laborious environment. He also experienced an unsettled economy and seasonal conditions that made construction a less reliable career than he thought. He decided to leave the construction industry and pursue a degree in engineering.
Steve started his education as a civil engineering major, thinking his prior construction experience would complement his studies. Early in his academic career, Steve attended a guest lecture on shape memory alloys given by Dr. Peter Mullner, Boise State University distinguished professor. He was fascinated and intrigued by how materials could be engineered at the atomic level. Dr. Mullner’s presentation led Steve to change his major to materials science and engineering, where he continues to make great strides in research and education.
Steve’s research deals exclusively with nuclear graphite, which is commonly used as a moderating material as well as a key structural component in nuclear reactor designs. Graphite accumulates irradiation damage when used in reactors over time. During irradiation, significant changes to the crystalline structure of graphite occurs. These changes adversely affect the mechanical properties of nuclear graphite, resulting in less optimal performance. Accurately predicting a component’s in-service lifetime can be challenging. It is difficult to monitor the dynamic response of graphite during irradiation at the atomic level. In situ monitoring of the atomic level response of graphite in nuclear reactors remains impossible; however, in situ transmission electron microscopy (TEM), offers a way to monitor this process. TEM utilizes a beam of high energy electrons which is transmitted through a specimen to form an image. In the case of graphite, these high-energy electrons readily displace carbon atoms which results in irradiation damage to the graphite structure that is arguably comparable to irradiation damage from neutrons found in nuclear reactors. As such, one may observe the atomic level response of graphite when subjected to irradiation ‘live time’ with the use of a TEM.
Steve first experienced electron microscopy as an undergraduate at Boise State. He was introduced to this technique while working with Dr. Mike Hurley, assistant professor. “I am forever grateful to Dr. Hurley’s research group for providing me the opportunity to be trained on this characterization technique. This greatly influenced my decision to accept an offer conducting TEM studies on nuclear graphite for my Ph.D. research, working alongside Dr. Karthik Chinnathambi at the BSCMC. Steve’s research is funded by the U.S. Department of Energy’s EPSCoR national laboratory partnership program. Steve actively collaborates with partner scientists from the Idaho National Laboratory. He has performed TEM experiments at the IVEM-Tandem facility at the Argonne National Laboratory and soon will be visiting the National Electron Microscopy Center (NCEM) at the Lawrence Berkeley National Laboratory. Continuing my education has changed my life and has created opportunities I never thought possible,” Steve says.
Life certainly can change. Steve quotes Seneca when reflecting on how his life has changed: “Luck is what happens when preparation meets opportunity.” Steve suggests that we all make our own luck, and to be proactive in doing so. Returning to school after a career in construction and learning an entirely new field might seem challenging. It is. Life goes on and people, like Steve, have families and other responsibilities that become top priorities. Steve proves that one can reach for new career opportunities at any time in life. As a bonus, he has a great opportunity to set an example for his children. “I would like to believe my display of hard work and determination, which has resulted in success, has influenced and played a role in my children’s lives. Both of my children excel in their studies and are amazing at anything they put their minds to,” says Steve.
Finding a job that involves electron microscopy and conducting research with a TEM would be Steve’s dream job. Based on his academic success, this dream can, and will, become Steve’s reality.