Abstract:
Selective laser sintering (SLS) is a powder-based layer-additive manufacturing process
generally meant for rapid prototyping and rapid tooling. Laser beams either in continuous
or pulse mode are used as a heat source for scanning and joining powders in predetermined
sizes and shapes of layers. The geometry of the scanned layers corresponds to the various
cross sections of the computer-aided design (CAD) models or stereo lithography (STL) files
of the object. Selective laser sintering has been used to make models for design testing,
patterns for investment casting, and small lots of functional parts. But with SLS, it is
sometimes difficult to achieve the best quality in appearance with the best mechanical
properties and it is time consuming and inefficient too. So, it is important to obtain a better
understanding of the relationship between powder properties, fabrication parameters in the
SLS process, and the parts produced using this process. So, this thesis aims to find the
optimum quality and better efficiency by setting these parameters differently according to
powder properties and requirements of application. It is therefore required to optimize the
relationship between the fabrication parameters and powder properties. This thesis aims to
relate fabrication parameters with powder properties and they are: laser power ratio, layer
thickness, grain size etc. In this thesis, optimization tool has been used to obtain suitable
fabrication parameters to satisfy the demands of specific applications. Finally, the research
direction is therefore a means of balancing in-process parameters with post-process
parameters in order to meet the requirements for good overall quality components and better
efficiency with minimum time and effort.
