CE Seminar by Dr.Sheng Guo

Time: 13:10
Location: ENG 208






Speaker: Dr. Sheng Guo

Title:  Physical Metallurgy of High-Entropy Alloys

Date: Monday,March 19th

Time: 13:15

Place: ENG 208

Host: Demircan Canadinç



By definition, an alloy is a mixture of metallic elements, or a mixture of metallic elements and other non-metallic elements.  In the history of alloy development, people have seen the wide application of alloys like steels, aluminum alloys and nickel based alloys. In almost all of these mature alloys systems, there is always one dominant alloying element (for example, Fe in steels), and it is this dominant element that plays the decisive role on the properties of the alloys. Since about 15 years ago, there has been a new trend in designing alloys in the physical metallurgy community, which differs significantly to previous practices. In the new category of alloys, there is no longer a clear distinction of dominant alloying element and other elements, and basically all alloying elements are mixed equiatomically or close to equiatomically. This novel alloy design strategy opens up a vast unexplored compositional space, and potentially new opportunities to numerous new materials and new applications, but also brings new challenges on how to design these alloys properly. This new category of highly concentrated multi-component alloys have been termed as multi-principal-element alloys or compositionally complex alloys, but they are better known as high-entropy alloys (HEAs) nowadays. In this seminar, I will give an overview of HEAs from the physical metallurgy perspective, starting from the definition, moving to the alloy design strategies that are currently adopted to HEAs, and then some typical properties of this relatively new class of metallic materials. Some of my previous and current research areas in this field will also be briefly mentioned. 




Dr. Sheng Guo is currently an Associate Professor at the Department of Industrial and Materials Science, Chalmers University of Technology in Sweden. Sheng joined Chalmers as an Assistant Professor in 2013, and was promoted to Associate Professor in 2016. Before joining Chalmers, Sheng spent four years working as a postdoctoral researcher in two universities in Hong Kong, City University of Hong Kong, and Polytechnic University of Hong Kong, respectively.  Sheng got his PhD in Materials Science from University of Oxford, United Kingdom in 2009, his master degree in Materials Science and Engineering from Central South University, China in 2005, and bachelor degree in Powder Metallurgy from the same university in 2002. Sheng’s research activities nowadays are focused on alloy design and mechanical properties of highly concentrated multi-component alloys, known as high-entropy alloys, but he is also actively looking for opportunities to expand his research areas to functional properties of novel metallic materials. Somehow, that explains why he is now at Koc Univ.