MULTI-FIELD SIMULATION OF THE SPARK PLASMA SINTERING PROCESS

Open Access
Author:
Yang, Hui
Graduate Program:
Engineering Mechanics
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
April 30, 2010
Committee Members:
  • Albert Eliot Segall, Thesis Advisor
Keywords:
  • temperature
  • spark plasma sintering (SPS)
  • stress
  • densification
Abstract:
Spark plasma sintering (SPS), also known as field assisted sintering, plasma activated sintering, pulsed electric current sintering, pulsed discharge pressure sintering, and/or the current activated sintering, which belongs to a class of techniques that use electric current to make sintering easier, is the most widely used electrically assisted sintering nowadays, even though the fundamental understanding of the principle mechanisms of SPS are not well established. In the present study, a finite element model capable of simulating the three-way coupling of thermal, electrical, and mechanical behavior of the SPS process, was developed using the commercially available ANSYS software for the purpose to obtain a precise insight of the cause of potential temperature and stress heterogeneities. Samples made from different materials, including alumina, ceria, copper, and tungsten with different aspect ratios were used in the simulation. Utilizing these parameters, the influences of material properties and aspect ratios on the temperature and stress distributions were then systematically investigated. In addition, an integrated experimental/numerical methodology was proposed, and the densification effect on the temperature and stress distributions was also considered by taking into account the temperature-density dependent properties of the sintering material. The model and the results provided herein are of paramount importance for understanding the phenomena in the SPS process, and can be used for the system design and process optimization that could subsequently lead to the reliable production of sintered structures with controlled and tailored properties.