طراحي، ساخت و ارزيابي سيستم ميكرواستريوليتوگرافي به روش تصوير كردن ماسك

چكيده انگليسي :

010 Design Fabrication and Evaluation of Mask Projection Micro Stereolithography System Ehsan Afiyoni Zadeh Esfahani e afiyoni@me iut ac ir Date of Submission 2016 06 22 Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Mohsen Safavi mosafavi@cc iut ac irAbstract The goal of this research is to design build and evaluate a mask projection micro stereolithography MP SL system MP SL is an additive manufacturing process based on photopolymerization that usesdigital light processing technology to selectively cure layers of photopolymer resin and fabricate a threedimensional part In this research the final performance of a MP SL system is dependent on the sum offunctional parts These parts are as follows Light source that produces the luminous energy and is projectedonto the resin surface to selectively cure photopolymer Conditioning optics that changes properties of theprojected light for MP SL applications Dynamic mask that digitally patterns and projects incident light toselectively cure photopolymer Projection orientation that is the position of the dynamic mask relative to thepolymer container Imaging optics that expand or reduce the projected image to achieve the desired imageresolution Recoat method that supplies liquid photopolymer over previous layers for the creation of newlayers Build platform that supports the object being made Vertical actuator that repositions the buildplatform for creation of the new layers Two different programs are needed for operating the manufacturingprocess One program is controlled the stepper motor and one is used to display the sliced images Photopolymer is the raw material used in MP SL to fabricate three dimensional objects In this processwavelengths of light between 380 to 420 nanometer are mostly used Layer thickness and exposure time areimportant parameters in this system Layer thickness and exposure time of resin are determined via workingcurve A total of 90 disk with 14mm diameter are cured by the manufactured system The exposure timewas varied from 1 seconds to 8 seconds in incremental steps of 500ms After solidification the samples arecleaned with isopropyl alcohol and are dried by air The thickness of the cured disks are then measuredusing a digital micrometer with an accuracy of 0 001mm and the corresponding working curve is plotted Layer thickness must be equal to the cured depth In this work layer thickness is considered as 20 micronand exposure time as 0 66s Performance of the photopolymer is determined via fabrication of a benchmarktest part Performance parameters consist of minimum feature size xy plane accuracy z axis minimumfeature size and z axis accuracy These parameters should be determined via experiment for photopolymerresin After determination of performance parameters xy plane and z axis dimensional error are specified The minimum feature size is equal to 50 micron and the z axis minimum feature size is equal to 20 micron Furthermore xy plane dimensional error is equal to 0 707 and z axis dimensional error is equal to26 502 Keywords Mask projection micro stereolithography Exposure time Layer thickness Benchmarktest part Performance parameters

افيوني زاده اصفهاني، احسان

طراحي، ساخت و ارزيابي سيستم ميكرواستريوليتوگرافي به روش تصوير كردن ماسك

زمان پرتودهي , ضخامت لايه , قطعه محك سنجي , پارامترهاي عملكردي