Influence of Thermal Annealing Temperatures on Powder Mould Effectiveness to Avoid Deformations in ABS and PLA 3D-Printed Parts

Abstract

Fused deposition modelling (FDM)-printed parts can be treated with various post-processes to improve their mechanical properties, dimensional accuracy and surface finish. Samples of polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) parts are treated with annealing to study a ceramic powder mould’s effectiveness in order to avoid dimensional part deformation. The variables chosen are annealing temperatures and the usage of a ceramic powder mould to avoid part deformations. A flexural strength test was carried out to evaluate the mould’s influence on the mechanical properties of the part. The effectiveness of the mould has been evaluated mainly attending to the length of the part, because this is the dimension most affected by deformation. A polynomial approximation to a deformation’s length and the effectiveness of the mould allows for their prediction. Results obtained show that effectiveness increases with the annealing temperature. Nevertheless, mould effectiveness decreases when parts are fabricated with PLA, because it is a semi-crystalline thermoplastic, and it suffers a lower shrinkage during thermal post-process than amorphous polymers such as ABS. Attending to the flexural strength test, mould has no significant influence on the mechanical properties of the treated parts in both materials studied.

Hangprinter for large scale additive manufacturing using fused particle fabrication with recycled plastic and continuous feeding

“…The limitation can be overcome in future work by using a stronger motor with a smaller gear ratio however, extra weight to the Hangprinter chassis only further limits acceleration and print speed. Furthermore, from the thermal image testing ( Table 27 , Table 28 ), it can be seen that the passive cooling system of two axial blower fans cooling the aluminum heatsink block does a satisfactory job of ensuring upper barrel temperatures do not exceed 60 °C, which is the glass transition temperature of PLA [86] . During extrusion tests with PLA pellet feedstock, no extruder clogs due to heat creep or cold starts up the barrel occurred even at 0 %, 50 % fan pwm.…”

“…During extrusion tests with PLA pellet feedstock, no extruder clogs due to heat creep or cold starts up the barrel occurred even at 0 %, 50 % fan pwm. Furthermore, with fan pwm at 100 % and nozzle temperature of 220 °C-240 °C, ABS granules with glass transition of 97 °C [86] can also theoretically extruded without risk of heat creep up the barrel.…”

An Environmentally-Friendly Three-Dimensional Computer-Aided Verification Technique for Plastic Parts

“…The second measurement object is a dashboard frame, which is a dark plastic part. The material of this part is made of ABS [ 22 , 23 ]. The characteristic of this plastic part is that the surface of the corner of the object is relatively smooth, which means that it easily produces reflections.…”

Development of a Three-Dimensional Optical Verification Technology without Environmental Pollution for Metal Components with Different Surface Properties

“…In this study, four metal components with different surface properties were used as measurement objects. It is important to note that the proposed environmentally friendly 3D optical verification technology can be employed for plastic products made of acrylonitrile butadiene styrene or polycarbonate [ 25 , 26 , 27 , 28 , 29 ]. In addition, the proposed environmentally friendly 3D optical verification technology can also be employed in the verification of feature sizes in the plastic injection mold [ 30 ], stamping die, blow molding mold [ 31 ], rotational molding mold, metal injection mold [ 32 , 33 ], or transfer molding mold [ 34 ].…”