Defects and Properties of Cast Metals IV: Poster Session
Sponsored by: TMS Materials Processing and Manufacturing Division, TMS: Solidification Committee
Program Organizers: Lang Yuan, University of South Carolina; Brian Thomas, Colorado School of Mines; Peter Lee, University College London; Mark Jolly, Cranfield University; Alex Plotkowski, Oak Ridge National Laboratory; Andrew Kao, University of Greenwich; Kyle Fezi, Fort Wayne Metals
Monday 5:30 PM
February 28, 2022
Room: Exhibit Hall C
Location: Anaheim Convention Center
F-26: Correlation between Purification Effect and Surface Segregation of Impurities in Aluminium at High Temperatures: Jin-Kyu Lee1; Sun-Ki Kim1; 1Nice LMS Co., LTD
Aluminum with high purities can be obtained by purification processes using segregation of impurity elements. One of the ways to segregate impurities is the surface enrichment of elements inside at high temperatures. Commercial aluminum has various impurity elements such as Fe, Si, Ti, Mg, Zn, etc. These elements also have different surface activities and concentrations in general pure aluminum. In this study, correlation between purification effect and surface segregation of impurities in aluminium at high temperatures were investigated. And also, the purification effects depending on impurity elements in aluminum were discussed. Thermodynamic calculation by FactSage 7.3 was also carried out to estimate formation of surface products by segregation of metallic impurities.
F-27: Modeling the Bonding and Structure of Non-metallic Inclusions within a Nickel Matrix during Forging: Brandon Mackey1; Thomas Siegmund1; Michael Sangid1; 1Purdue University
Forging of metallic materials requires both high temperatures and large plastic deformation. During this process, three-dimensional defects, such as non-metallic inclusions, are known to debond from the metallic matrix and break apart, which can result in a linear array of smaller inclusions, known as stringers. The presence of stringers can be detrimental to the fatigue life of the final forged component, especially when present near the free surface. By performing process modeling, we provide a contribution to the understanding of deformation and failure sequences leading to stringer formation. A finite element model combining both solid and cohesive zone elements is created within ABAQUS/Explicit to simulate the debonding and break up of an alumina inclusion in a nickel matrix, under isothermal forging conditions. Simulation results quantify the forging temperature, deformation per pass, and interfacial parameters effects on the interfacial decohesion and the onset of stringer formation throughout the forging process.
F-28: The Mechanical Properties and Microstructural of Cast Zinc though Aluminum Inoculation by Ultrasonic Treatment: Dachao Wu1; Zhilin Liu1; Zhaojin Fan1; Tian Huang1; 1Central south university
A series of problems, such as low strength, low ductility and brittleness caused by the hexagonal close packed (HCP) crystal structure and coarse grains of unalloyed high-purity zinc after solidification, limit the development of zinc alloys. In this paper, the high growth restriction effect of Al in Zn is used to achieve the transformation from columnar crystal to equiaxed crystal, which significantly improves the mechanical properties of the material. And under the synergy of high-energy ultrasound, the mechanical properties of the ingot are further improved.