STEREOLITHOGRAPHY Chris Hannigan Joe McCullough

WHAT IS IT?  Additive Manufacturing Process  Rapid Prototyping  First method of rapid prototyping developed by 3D Systems  Patented in 1986 by Chuck Hull billion-jobs-to-disappear-by-2030/

HOW DOES IT WORK?

CURING PROCESS  Liquid Photopolymer  Acrylic monomer  determines properties  Photoinitiators  Curing agent  Oligomer  Small monomer used to bond  UV Laser  Cures by wavelength  Typically nm  Blade Jacobs, Paul F. Rapid prototyping & manufacturing: fundamentals of stereolithography. Sme, w-200mw-100mw-50mw-uv-violet-laser-pointer- razor-series

POST-CURING  “Green” parts only cured 80-96%  Gaussian Energy Distribution  Post curing apparatus needed for further solidification  Ultraviolet chamber: 300 Watts  Microwave oven: 700 Watts  Thermal oven: 125˚C [1]

DISADVANTAGES  Cost  Initial  $100,000 -$  Resin  $300 per gallon  Shrinkage  Inaccuracies can occur during any phase  Tolerance must be monitored  Size of model  Low volume output

ADVANTAGES  Functional Prototype  Comparatively fast  Material Efficiency  Excellent Surface Finish

FUTURE OUTLOOK  Specific medical devices  Improvements in accuracy  Desktop Stereolithography  $3,299

PRINTED GUNS????

REFERENCE  [1]Salmoria, G.V., C.H. Ahrens, V.E. Beal, A.T.N Pires, and V. Soldi. "Evaluation of Post-curing and Laser Manufacturing Parameters on the Properties of SOMOS 7110 Photosensitive Resin Used in Stereolithography." Materials & Design (2009): Science Direct. Web