Seminar

학과 정기세미나 안내


 
■ 제목지식기반 첨단소재의 설계 및 이해를 위한 고분해능 특성평가 

(Correlative high-resolution characterization for understanding and knowledge-based design of advanced materials)

                    
■ 연사 : 최벽파 교수 (카이스트, 신소재공학과 부교수)


■ 일시 : 3 15 () 16:00
 
■ 장소 : 응용공학동 (W1) 1층 영상강의실


■ Abstract : 
Atom Probe Tomography (APT) is a high-resolution characterization method that enables three-dimensional elemental mapping with near-atomic resolution. Therefore, APT is highly useful for characterizing advanced materials and for understanding their structure-property relationships.

  This presentation gives an overview of the APT-related research done by the author. The materials systems which will be presented are advanced high-strength steels and nanostructured materials for various applications. These materials can undergo complex changes during synthesis and processing, and it will be discussed how local chemical changes such as nano-precipitation, segregation to internal interfaces and elemental partitioning across phase boundaries can significantly affect the material properties. Furthermore, we will emphasize the importance of correlating APT data with theoretical predictions, for instance made by ab-initio density functional theory, and with other experimental techniques such as transmission electron microscopy (TEM). It will be shown that information gathered from these different techniques can serve as a basis of a knowledge-based rather than empirical approach of designing advanced materials.

 Finally, we will present a new methodology for coupling chemical and crystallographic analyses at the atomic-scale, using joint APT / TEM nano-beam diffraction analyses on identical samples. This method has been used for quantifying solute segregation to grain boundaries in a nanocrystalline steel as a function of grain boundary character and misorientation.