MSE Seminar: Changdong Wei, Application of diffusion multiples to spatially-resolved measurements of physical properties and exploration of stable precipitates for high-temperature steels

Ph.D. Candidate advised by Dr. J.-C. Zhao

All dates for this event occur in the past.

145 Fontana Labs
116 W. 19th Ave
Columbus, OH 43210
United States

Abstract

The diffusion-multiple approach enables formations of wide ranges of compositions and large number of intermetallic phases for efficient mapping of phase equilibria relations, phase-based physical properties, phase transformation morphologies and kinetics, etc. It has orders of higher efficiency than the traditional individual alloy method to establish the composition-structure-property relationship, which provides very valuable information for new materials design and development. This talk will first describe the development of the high-throughput measurement of thermal conductivity (Λ), specific heat capacity (CP), coefficient of thermal expansion (CTE) using an ultrafast laser based pump-probe technique – time-domain thermoreflectance (TDTR). Based on the experimental thermal conductivity data on metallic alloy systems, a physics based quantitative model was developed to describe the compositional dependency, together with the density of states (DOS) calculated from first-principles. Precipitate morphology and phase transformation kinetics were also studies using dual-anneal diffusion multiples, to effective explore novel precipitation strengthening mechanism in a few Fe-based materials systems, to aid the design of high temperature steels for the advanced ultrasupercritical steam turbines (AUSC).

Bio

Changdong comes from China and he obtained his B.S. degree in Optical Science & Engineering from Fudan University in 2009. After that he joined Dr. J.-C. Zhao’s group as a PhD student in Department of Materials Science & Engineering at the Ohio State University and received his M.S. degree in 2012. Changdong’s research was focused on developing novel ultrafast laser metrology approaches of materials properties, and developing high-temperature high-strength steels by computational thermodynamics and high-throughput experimentation.