|
|
3D printed samples
|
|
|
==================
|
|
|
|
|
|
When the sample shape is too complex so that a backing mold cannot be made to [cast the photoelastic sample](https://git-xen.lmgc.univ-montp2.fr/PhotoElasticity/Main/wikis/molding-urethane) it is still possible to directly 3D print the it. 3D printing is not simple and it is even worse when you have to do it with a photoelastic material making sure there is no residual stresses. That is why you should not expect this way to make photoelastic samples as the ultimate one. It is good if you want to work with hard material (high loading) and that you can afford expensive samples. Also if you want to rapidly prototype a photoelastic sample and if your measurement accuracy is not too high, it still worth. In this section we go more into details about this method and the different options.
|
|
|
When the sample shape is too complex so that a backing mold cannot be made to [cast the photoelastic sample](https://git-xen.lmgc.univ-montp2.fr/PhotoElasticity/Main/wikis/molding-urethane) it is still possible to directly 3D print it. 3D printing is not simple and it is even worse when you have to do it with a photoelastic material making sure there is no residual stresses. That is why you should not expect this way to make photoelastic samples to be the ultimate one. It is good if you want to work with hard material (high loading) and that you can afford expensive samples. Also if you want to rapidly prototype a photoelastic sample and if your measurement accuracy is not too high, it still worth. In this section we go more into details about this method and the different options.
|
|
|
|
|
|
|
|
|
Stereolithography
|
|
|
-----------------
|
|
|
|
|
|
The easiest and most democratic way to 3D print photoelastic samples is to use [stereolithography](https://en.wikipedia.org/wiki/Stereolithography). However, even if it does not induce residual stresses you end up having a stiff and not very transparent material so that it is barely usable. In the picture below where the sample have been printed with a [Form-2](https://formlabs.com/3d-printers/form-2/) from [Formlabs](https://formlabs.com), even by bending strongly the sample, photoelastic response is rather weak and blurry. So this method is only valid for large loading when you just expect a qualitative measurement.
|
|
|
|
|
|
![IMG_9795.resized](uploads/82a211c688ce57adbbbd40a103cd0657/IMG_9795.resized.JPG)
|
|
|
![IMG_9794.resized](uploads/736551685e78a101572e520c06308195/IMG_9794.resized.JPG)
|
|
|
|
|
|
|
|
|
Fused Filament Fabrication
|
|
|
--------------------------
|
|
|
|
|
|
To 3D printing a photoelastic sample an other option exist: using Fused Filament Fabrication technology with transparent material. Generaly speaking this is not the best option with cheap 3D printer since it induces a lot of residual stresses and porosity that make the sample barely transparent. Still the company [Stratasys](https://www.stratasys.com/) proposes a quite recent material called [Veroclear](https://www.stratasys.com/materials/search/veroclear) which is perfectly clear and as photoelastic (and stiff) as plexiglass.
|
|
|
The main drawback here is that the material is very stiff and expensive just like the printing techonology.
|
|
|
|
|
|
https://www.nature.com/articles/s41598-017-11433-4
|
|
|
|
|
|
https://formlabs.com/fr/3d-printers/form-2/
|
|
|
https://www.stratasys.com/
|
|
|
https://www.stratasys.com/materials/search/veroclear
|
|
|
|
|
|
stratasys VeroClear but large modulus quite expensive
|
|
|
other like stereolito poorly transparent and photoelastic material quite brittle good only for 'rapid' prototyping
|
|
|
|
|
|
![IMG_9795.resized](uploads/82a211c688ce57adbbbd40a103cd0657/IMG_9795.resized.JPG)
|
|
|
![IMG_9794.resized](uploads/736551685e78a101572e520c06308195/IMG_9794.resized.JPG)
|
|
|
|
|
|
make 3D shape not always reachable with molding processes
|
|
|
|
|
|
|
|
|
[<go back to home](https://git-xen.lmgc.univ-montp2.fr/PhotoElasticity/Main/wikis/home) |
|
|
\ No newline at end of file |