Thermal Expansion of RP-models

From: Ulrich Laible (Clemson University), Jim Bakkelund (Narvik Institute of Technology)
Date: Friday, March 17, 1995

From: Ulrich Laible (Clemson  University), Jim Bakkelund (Narvik Institute of Technology)
To: RP-ML
Date: Friday, March 17, 1995
Subject: Thermal Expansion of RP-models
Ulrich Laible writes:

*Does anybody has some data about the thermal expansion of RP-materials in the
*finished state (what means after postcuring, sintering, or whatever)

*This will be of concern, whenever the accuracy of RP-parts is either measured 
*for experiments or is important for applications. Does it make a big difference 
*if I measure at 68(20) or 77(25) degree F(C) ? 
*I could find no proper information in datat-sheets from the supplier.

*I am specially interested in data for the DUPONT SOMOS 3110 resin for 
*Stereolithography, since we are going to do experiments with that.

*But I would also be interested in the thermal expansion of any other 
*RP material, for SL, SLS, SGC, FDM, LOM
---------------------------------------------------------------------------

We are using a SLA 250, and from CIBA-GEIGY I have got data sheets for the 
SL 5170 Epoxy resin.
The sheet contains data about mechanical, thermal, electrical and optical
proporties of cured resin. It also contains data about solvent resistance
and humidity effects.

You ask about thermal expansion, and it is quite clear that all matter changes
with teperature. This fact also yelds for the resins for rapid prototyping.

>From the data sheets for the SL5170 I can read that the thermal expanction
from 20 to 40 degree C was 0.1mm.
But it is not that simple, you have also to think about the air humidity and
the storage time. 
A part stored under a dry atmosphere will shrink and lose weight, 
a part stored under a humidity of 80% will expand, absorbe water and change
weight, undependent of the room temperature.
It is also clear that parts build with different building styles will 
change differently.

I hope this could help, and if you would like the data sheets
just mail me your fax number, and I will fax these to you.

Jim Bakkelund
Narvik Institute of Technology, Norway
jb@gauk.sin.no


Previous message | Next message
Back to 1995 index