Porous Structures via Selective Laser Sintering: A Route to Functional Preform Production

摘要

Selective laser sintering (SLS) is a rapid prototyping (RP) method in which three-dimensional objects are constructed by sintering thin layers of a variety of powdered materials. As in most other RP methods, the parts produced by SLS exhibit varying degrees of intrinsic porosity, which is mostly an undesired trait due to reduced part integrity. However, there are a number of emerging or potential applications, as in the fields of tissue engineering and composite materials, in which parts with controlled porosity is desirable.This paper presents an ongoing research in which the manufacturing capabilities of SLS are investigated for producing predesigned polymeric porous structures. The porous structures are characterized in two main categories: regular porous structures, which involve geometries that have orderly pore architecture, and irregular porous structures, which exhibit random pore architecture that is intrinsic in all SLS parts. The limitations of producing regular porous structures are identified and quantified based on pore size. For irregular porous structures, a parametric study based on design of experiments is conducted to relate process parameters to the macroscopic pore properties.