# Experimental Investigation on Effect of Temperature on FDM 3D Printing Polymers: ABS, PETG, and PLA
## 3 Results
On each plot, the vertical axis is the y position, the horizontal axis is the x position, and the color gradient represents the time (i.e., starting from light to darker colors as time passes). It is clear that PLA is more responsive to temperature changes and ABS has the minimum response. Additionally, it can be seen that the horizontal motion of the end of 3D-printed parts is more drastic than the vertical axis. This can indeed be due to the geometry defined for the parts. Figure 4: Absolute x position vs. time: different colors on each plot represent different samples studied in each category: (**A–C**) are ABS material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. (**D–F**) are PETG material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. (**G–I**) are PLA material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. The other parameter that is crucial to the design of circular geometries is the radius of curvature. Figure 7 represents how the radii of curvature for each material (ABS, PETG, and PLA) were changing given different temperature dosages as time passed. It should be emphasized that drastic changes occurred in the first 50 s. However, the parts were still moving (although slowly) until the end of each curve. It is a general trend for all materials that a higher temperature would cause a lower radius of curvature during the cooling process. Additionally, the rate of change of curvature for PLA was much higher than that of other materials. Figure 5: Absolute x velocity versus time: different colors on each plot represent different samples studied in each category: (**A–C**) are ABS material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. (**D–F**) are PETG material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. (**G–I**) are PLA material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. Figure 6: Y position versus x position versus time (time is represented by the color gradient going from light to dark): (**A–C**) are ABS material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. (**D–F**) are PETG material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. (**G–I**) are PLA material heated at 85 \({}^{\circ}\)C, 105 \({}^{\circ}\)C, and 125 \({}^{\circ}\)C, respectively. Finally, each sample was heated and cooled down three times in order to study the effect of multiple heating and cooling processes on the properties of the polymers. For each configuration, the maximum x position and radius of curvature were averaged and plotted as shown in Figure 8. It is clear that PETG does not necessarily curl more if heated to a lower or higher temperature. On the other hand, PLA is heavily dependent on the heating temperature. Additionally, it is noted that the curling phenomenon gets diminished as we increase the number of heating and cooling cycles. ABS's 3D-printed parts follow the same trend as PLA's but with lower changes in magnitudes. Therefore, if the application requires a fast and drastic response of 3D-printed parts to temperatures, PLA would be ideal. If they want a slow but continuous response, ABS is recommended. PETG can perform well in 4D printing; however, lower or higher temperature does not improve its performance. Additionally, it should be noted that although cycling the heating and cooling procedures might be beneficial for achieving the desired geometry, the strength of the final parts might be diminished. This is studied in more depth by [PERSON] et al. (2015). Finally, it should be noted that a higher number of cycles can reduce the maximum range of displacement provided by the samples.