The micromechanical influences on the constitutive laws of sintering for a continuum model.

摘要

The constitutive laws of sintering govern the rheological response of a powder body during sintering by considering the body as a homogeneous, porous continuum. This study examines these laws and links micromechanical information to the key parameters, characterizing these laws and the continuum model. Flaws in the current formulation, as well as the inclusion of a new parameter to overcome the shortcomings of this model are given. The necessity of the study is illustrated through crucial experiments and validated through finite element simulations of these experiments. The CREEP subroutine of the finite element code AbaqusRTM is based on the continuum model, using the constitutive laws of sintering. Comparison between the model as it is currently utilized in industry and with the adjustments suggested in this thesis is conducted. The material used to explore these topics is nickel powder, consolidated through the injection-molding technique.