Helmond, The Netherlands, 13th of February 2020
Usually for every material a print profile is made with which the filament can be printed and gives a good print with a nice looking exterior. In order to optimize the tensile strength of the material a lot of settings have been varied, one at a time, to find out if there is a relation between a specific parameter and the tensile properties of the material (tested according to ISO-527). Some parameters showed a clear trend while other parameters did not. The following paragraphs give some more information about three settings that turned out to be important for improving the tensile strength, the Print Temperature, Fan Speed, and whether using an Enclosure or not.
Parameter 1: Print Temperature
In order to get a good layer adhesion it is important that the layer has the right temperature in order to properly bond to the new layer that is placed on top. One of the important settings which plays a role in the temperature of the material is the Print Temperature, the higher it is the hotter the layer will be, with limitations of course due to degradation. When increasing the Print Temperature an increase of 106% Stress at Yield could be achieved (vertically printed (Z)).
Parameter 2: Fan Speed
Just like the Print Temperature the Fan Speed also plays an important role in obtaining a good layer adhesion. The lower the Fan Speed the higher the temperature of the material will be when the new layer is placed on top. When decreasing the Fan Speed an increase of 156% in Stress at Yield could be achieved (vertically printed (Z)).
Parameter 3: Enclosure
When using an enclosure the material will remain having a higher temperature during printing than when printing without an enclosure. The higher the temperature of the material will be when a new layer is placed on top will result in a better bonding of the layers. When using an Enclosure compared to not using an Enclosure an increase of 78% in Stress at Yield could be achieved (vertically printed (Z)).
Some parameters will affect the Stress at Yield a lot while other parameters still have a significant influence but the differences will not be that major. Multiple interesting trends were found and after extensively testing the influence of the print settings on the tensile properties an optimized print profile was made. This also included a printability test, since the model still needed to have a proper looking exterior. All parameters have been printed both horizontally (X-Y) and vertically (Z). Both print orientations had an increase in tensile strength but the vertical (Z) printed tensile bars showed the best improvement, the optimised print profile has an overall improvement of 206% in Stress at Yield compared to the basic print profile while still having a good looking exterior.