Reducing the surface deviation of stereolithography components

Reeves, Philip E. (1998) Reducing the surface deviation of stereolithography components. PhD thesis, University of Nottingham.

[thumbnail of 263458.pdf]
Preview
PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
Download (36MB) | Preview

Abstract

The Stereolithography (SL) process has developed into an accurate method of replicating 3D CAD images into tactile objects used for functions such as product evaluation, preproduction testing or as patterns around which tool cavities can be formed. One of the main limitations with the SL process is the surface roughness of parts resulting from the layer manufacturing process. To-date surface roughness has only been reduced using techniques such as additive coating or abrasive finishing. Research has shown however, that these techniques are both detrimental to the accuracy of parts and can prove to increase the cost of SL parts to the end user.

The object of this research is to assess the fundamental cause of surface roughness in layer manufacturing and develop techniques that can be used during the build process to produce SL parts with lower surface deviation. To do this a comparison of the most common commercial RP systems was undertaken to identify the attributes causing surface deviation. From these attributes a mathematical model of layer manufactured surface roughness was developed. Parts manufactured using different SL machines were compared to the mathematical model showing a variety of causes in surface deviation not considered in earlier research, such as layer composition, layer profile and the affects of over curing or print-through on surface deviation. The layer edge profile caused by the shape of the scanning laser also has a significant effect on roughness deviation. However, by using a combination of part orientation and optimal shaped meniscus smoothing, the surface deviation of SL parts was found to be reduced by up to 400% on at least 90- degrees of continuous surfaces. A better understanding of layer manufactured surface roughness has now been achieved and a new smooth build algorithm has been developed.

Item Type: Thesis (University of Nottingham only) (PhD)
Supervisors: Cobb, R.
Keywords: Finishing, Layer manufacturing, Manufacturing processes, Pattern recognition systems, Rapid prototyping, Rapid tooling
Subjects: T Technology > TS Manufactures
Faculties/Schools: UK Campuses > Faculty of Engineering > Department of Mechanical, Materials and Manufacturing Engineering
Item ID: 13191
Depositing User: EP, Services
Date Deposited: 04 Apr 2013 13:20
Last Modified: 19 Dec 2017 13:38
URI: https://eprints.nottingham.ac.uk/id/eprint/13191

Actions (Archive Staff Only)

Edit View Edit View