CAREER: Role of Ternary Alloying Elements in Eutectic Solidification

University Of Alabama At Birmingham, Birmingham AL

Investigators

Abstract

Non-Technical Abstract The process of microstructure formation during solidification in multi-component metal alloys is of great interest from both a fundamental scientific and an applied point of view. One particular class of materials, called eutectics, includes everything from cast iron to lead-free solder to self-assembling composites. New experimental data is necessary to develop theories and models that can accurately predict the behavior of these complicated materials, enabling their use in advanced applications. A variety of carefully controlled experimental conditions will be used to investigate the behavior of selected three-component eutectic systems. State-of-the-art and novel techniques for solidification will be used to investigate the relationships between processing parameters, structural details and material properties. The work also includes a well-rounded program for the recruitment and professional development of graduate, undergraduate, and high school students in the field of materials science and engineering. This work includes the organization of a Materials Camp program for area high school students. The PI will work with UAB's Center for Community OutReach Development (CORD) to expand the diversity of the applicant pool as well as to improve curriculum and assessment tools for the program, which will be shared with other Materials Camps across the country. Finally, the PI will use her international experience to develop global competency in undergraduate STEM students through redeveloped history courses taught both on campus and abroad. Technical Abstract As part of the larger class of multi-component, multi-phase materials, eutectics structures are of both fundamental and applied interest. While binary eutectics with non-faceted interfaces are relatively well understood, theories describing the structure and behavior of more complicated eutectics - those with three or more phases and/or with faceted interfaces - are not well developed. These complex eutectics have received renewed interest in recent years for their potential as in-situ composites and self-assembling metamaterials, but better control of microstructure development is needed to realize these advanced applications. A variety of carefully controlled experimental conditions will be used to investigate the behavior of selected ternary eutectic systems, both regular and irregular. State-of-the-art techniques for directional solidification, along with a novel method of equiaxed solidification, will be used to investigate the relationships between anisotropy, crystal mismatch, non-equilibrium pattern formation, alignment of interphase boundaries, prevailing orientation relationships, and the evolution of crystallographic texture. In addition, the role of ternary elements on eutectic spacing and interface stability will be elucidated through in situ and post processing observation. This proposal includes a well-rounded program for the recruitment and professional development of graduate, undergraduate, and high school students in the field of materials science and engineering, building on the PI's established track record in these areas. Graduate and undergraduate student researchers from UAB's diverse student body will carry out the research, developing experimental, analytical, and communication skills that will prepare them for future careers in industry and academia. These students will assist the PI in organizing and running a summer Materials Camp program for area high school students. The PI will work with UAB's Center for Community OutReach Development (CORD) to expand the diversity of the applicant pool as well as to improve curriculum and assessment tools for the program, which will be shared with other ASM Materials Camps across the country. Finally, the PI will use her international experience to develop global competency of undergraduate STEM students through redeveloped history courses taught on and off campus.