Featured in the issue is an article called “Critical Characteristics Affecting the Surface Finish of Coatings”, written in part by Nathaniel Bryant with guidance from MCC Director, Jerry Thiel, and based on Bryant’s presentation of the research at the American Foundry Society’s 121st Metalcasting Congress that took place in Milwaukee, WI.
Bryant is currently a graduate student at the University of Northern Iowa studying technology and working at the Metal Casting Center. During the summer of 2016, he took an internship with Oak Ridge National Laboratory in Knoxville, TN and began his initial investigation on this topic. “But it turned into something larger than what I could accomplish in one summer,” says Bryant. Luckily, when he returned to UNI in the fall MCC and ORNL were able to sign a cooperative research agreement so that Bryant could continue his research in Cedar Falls.
And he did continue his research through September 2016 before compiling all of his results into his research paper. Overall, he found the results to be similar to trends he investigated during the literature review process of the project. “After that, I looked at sand from a different perspective,” he continues. “Rather than measuring surface finish according to average grain diameter, I looked at it against the surface area. This was significant because it took into account the grain shape of the aggregate as well as the overall distribution width. We were able to find repeatable results when looking at it this way.”
Bryant was also able to do some testing that to his knowledge had not been done before which involved the contact angle of gallium. “Gallium is interesting because it is the only metal that is in a liquid state at near room temperature. This property was useful to us because we were able to use pure gallium to investigate the surface wetability of materials. It was originally assumed that the material composition of the substrate had the most significant impact on contact angle, but from our results, an argument can be made that grain shape (or sphericity) is the critical factor.”
Overall, the research project was successful at investment cast surface finishes in sand cast parts. However, this was only met with the traditional method and not with new technology. And in true MCC fashion, they are not stopping here.
“While other universities are moving away from research in basic materials such as sands, refractory, and resins, UNI continues to specialize in foundry material characterization and testing that provides the industry with valuable information and students with specialized education," explains Thiel. “Ninety percent of the research at UNI is completed by undergraduate students under the direction of full-time technical staff and academic faculty. The MCC currently employees 25 undergraduate and graduate students who gain advanced knowledge and experience in manufacturing while financing their education. The UNI student advantage has been noticed by the industry and is one of the main reasons our students are highly recruited.”
Bryant is currently involved in developing a new methodology to measure cast roughness with an optical method and we will hopefully have a paper on that later this year. Additionally, another opportunity may be in the future for Bryant. “After I presented my research, a refractory coating company has begun development of new coatings to improve cast roughness of 3D printed materials. I'm not sure if I'll be involved in it, but I hope that my master's thesis involves this subject,” he explained.
“The best part about doing a research project is that the overall goal is to help the industry we love. For us researchers it’s not about accolades or recognition that we've discovered something, but rather that there is a facility out there that will improve because of our work and dedication,” Bryant says. “I can rest easy knowing that.”
Bryant received his undergraduate degree in manufacturing technology with an emphasis in metal casting in the summer of 2017 and has been working with MCC since 2013. “I decided to continue for my masters because the Director of the Metal Casting Center (Jerry Thiel) convinced me that I have a knack for research and that it would be worth pursuing. It was an easy choice for me to pick UNI since I have a great relationship with the MCC and AMC staff as well as the professors and administration in the department of technology. I have great respect for Jerry Thiel, Sairam Ravi, and Dr. Scott Giese who have been with me every step of the way. I hope to learn as much as I can from them in the next couple of years,” Bryant concluded.
Additionally, Bryant’s first year of graduate school will be sponsored by ORNL. You can check out the research in the September 2017 issue of Modern Casting Magazine here on pages 30-32 or read it on the American Foundry Society website here.