Measurement and topography characterization of surfaces produced by Selective Laser Sintering

Selective Laser Sintering (SLS) permits to manufacture physical models, suitable to be used as sand moulds in the casting processes. SLS presents some technological limits as regards the dimensional precision and surface roughness, which require an accurate assessment. Unfortunately contact methods are not able to carry out these measurements. This paper investigates the possibility of using a new non-contact instrument based on conoscopic holography to measure both microgeometry and macrogeometry of SLS samples. The reliability of measures and its influence on roughness parameters is discussed. A procedure for characterizing and identifying the sample edges is introduced.