Design and Toughening of High-performance Alloy Coatings and Heat­resistant Aluminum Alloys based on Theoretical Calculations.

Sida Liu

 Laboratory for multiscale mechanics and medical science, SV LAB, School of Aerospace,

Xi'an Jiaotong University, Xi'an 710049, China; 

EXTENDED ABSTRACT: Due to the low solid solubility of Mn and the limited quantity of Mn precipitates, A-Mn alloys exhibit poor ageardening resonse,wit much smaller hardening increment compared to commonly aged-strengthened aluminum alloys. In recent yearsvarious chemical elements have been introduced into Al-Mn alloys, mostly Zr, ScSn Mo, etc., for improving the mechanical properties ofthe alloy by regulafing the precipitation eficiency of the alloy phases or forming dispersed nano-precipitation phases, with the purpose oimproving the heat treatment strengthening of A-Mn alloys.Nevertheless. the improvement potential of the compositional controlmethodis gradually limited, leading to the inevitable choice of developing a completely new system for high-strength and tough Al-Min alloysAdditionally, a significant amount of researchhas focused on the development of alloy processing techniques, such as twin-roll castingand severe plastic deformation.to regulate the microstructure of Al-Mn allovs and achieve alloy strengthening. However. the eftectivenesof these techniques has been limited. Studies have found that by utilizing physical vapor deposition methodspossible to combinecrystalline and amorphous phases. resulting in the productionof composite-structured alloys that exhibit superior yield strength and uniform*uctlity, it has been reported that hign-trength and tough Al-based multicomponent alloys with a "crystallme-amorphous" nano-dual thaserStricture can be prepared using magneron sputtering techniques. it can be anticipated that by adding trace elements X (X = Ru or Pd) to AlMn binary alloys and ufilizing the advantages of the nano-dual phase structure. a novel "crystalline-amorphous" nano-dual phase Al-Mn-Xternary alloy can be developed, which will play a signifcant role in enhancing the mechanical properties of the alloyDuring the process of alloy material fabricationusing magnetron sputtering, the system deviates from equilibrium and easily obtainsmetastable phases. By combining computational method.s such as CALPHADwith experimental techniques, a phase diagram of metastabltphases can be constructed for the system, allowing for the investigation of the infuence of chemical composition and fabrication processeon material stricture, and subsequently evaluating the performance of materials uder different structhures. For instance, a ternary aluminumbased metastable phase diagrambased on CALPHAD and key experiments is used to describe the phase formation behavior0007914t241of commonly used hard coating material Al-Ti-N in industrial production. Similarly, the construction of a thermodynamic database foithe Al-Mn-X system facilitates the understanding of the influence of chemical composition on phase formation in the alloy, therebyproviding theoretical guidance for the development of high-strength and tough Al-Mn-based nano-dual phase alloys. This proiect envision:expanding existing research methods by integrating theoretical calculafions, experimental fabrication, electrochemical testing, and advancedcharacterization techniques to eficiently establish the correlation beween composition, structure, and mechanical properties in the A-Mnsystem, ultimately leading to the fabrication of high-strength and tough A1-Mn-X allovs.

Keywords:magnetron sputtering:nano-dual phase: metastable state: thermodynamic calculation

Brief Introduction of Speaker
Sida Liu

Sida Liu is a professor and doctoral supervisor of Xi'an Jiaotong University who is a National Young Talent. He serves as a core member of the "Multiscale Mechanics" teant at the National Key Laboratory of Mechanical Structural Strength and Vibration. His research focuses on the design, development, and industrialization of metal materials, particularly crystal-seed alloys for lightweight alloys. He has independently developed a high-performance hydrogen evolution catalyst, Al-Mn dual-phase nanostructure, which can be produced in large quantities. This catalyst outperforms commercial platinum-carbon catalysts in terms of both performance and cost, and patent applications have been filed in China and the United States. Liu has also independently designed and refined a series of Al-Ti-B-C (TCB) crystal­seed alloys, which have been exported to over a dozen countries, including Germany, Italy, and South Korea. These alloys have gained significant traction in companies such as China Aluminum, Huawei, and US Gateway. As a first or corresponding author, he has published papers in prestigious journals such as Science Advances, Acta Materialia (3), and Advanced Science. Additionally, Liu serves as a young editor for journals including Nano Research Energy, Materials Research Letters, and Journal of Metals (English Edition). He has led or participated in numerous research projects, including the Ministry of Industry and Information Technology's overseas high-level talent program, Hong Kong Innovation and Technology Fund (GFR), and the German National Science Foundation (DFG). In 2022, he was honored with the highest award in the "Chunhui Cup" China Overseas Talents Innovation and Entrepreneurship Competition, recognized by the Ministry of Education. His research achievements have been featured in media and institutions such as CCTV International and the German Academic Exchange Service (DAAD).