EXTENDED ABSTRACT: The precipitation and its corresponding microstructure in titanium alloys have a significant impact on comprehensive mechanical performance. Alloying and heat treatment processes are the primary means of regulating titanium alloy microstructures and optimizing mechanical properties. The presenter conducted research using coupled thermodynamic databases, phase-field dynamic simulations, and experimental characterization to investigate the influence of alloy composition, heat treatment temperature, and cooling rate on the microstructure of titanium alloys. At lowtemperature aging and near the critical alloy composition, a novel mechanism with high nucleation density and fine precipitate size, termed pseudoquenching decomposition, was discovered. By designing multi-step aging, primary precipitate phase dissolution, and controlling the cooling rate, an effective approach based on the pseudoquenching decomposition mechanism was proposed for designing multi-scale microstructures in titanium alloys. This approach further guided experimental design to achieve corresponding multi-scale microstructures in titanium alloys and improve their strength and toughness.
Keywords：Titanium alloy; Precipitation; Phase field; Multi-scale microstructure
REFERENCES:[1] Acta Materialia 257 (2023) 119182;Acta Materialia 269 (2024)119810;Materials Science & Engineering
A 829 (2022) 142117;Journal of Materials Science & Technology 124 (2022) 150–163
Dong Wang is a professor and doctoral supervisor at the FIST of Xi'an Jiaotong University. He has been approved for the Shaanxi Province Hundred Talents Program Young Project, the Shaanxi Province Outstanding Youth Fund, and the Young Top Talent Program at Xi'an Jiaotong University. Since 2011, he has conducted research on computer simulation-assisted design of microstructures in materials. His work includes establishing microstructural evolution models for ferroelectrics and lightweight structural materials, revealing mechanisms for regulating nanodomain structures in shape memory alloys, and designing narrow hysteresis superelastic properties over a wide temperature range. He also optimizes theoretical designs for high dielectric and wide temperature range performance in ferroelectric materials and integrates computation and experimentation to propose multi-scale precipitate structures and strengthtoughness coupled titanium alloys. He has obtained three projects funded by the National Natural Science Foundation, one project under the National Key Research and Development Program, participated in two 973 Program projects, and one key project funded by the Natural Science Foundation. As the first author or corresponding author, he has published over 80 papers in journals including Phys Rev Lett (2 papers), Acta Mater (14 papers), and Adv Funct Mater (4 papers).