Colloquium announcement

Faculty of Engineering Technology

Department Production Technology (MS3)
Master programme Mechanical Engineering

As part of his / her master assignment

Hendriks, R.J.M. (Roy)

will hold a speech entitled:

UV assisted Additive Manufacturing of a liquid thermoplastic resin: A study on interphase formation

Date26-02-2021
Time09:00
RoomTeams

Summary

Additive manufacturing (AM) of thermoplastics shows a high potential to produce complex parts for the aerospace industry. Currently, the quality of the bonding between the beads and laminas is insufficient. Besides, printing with thermoplastics is also associated with a high void content and thermal degradation. Hence, a liquid thermoplastic resin is used to overcome the problems. Herein, a commercial thermoplastic resin is used in an AM technology based on reactive liquid deposition modeling (RLDM).

 

The main focus is to characterize and optimize this resin for room temperature AM processes by studying the interphase formation. In this project, an understanding of the resin reaction with the thermal initiator (TI) at temperatures between 35°C and 60°C and with a photoinitiator (PI) is obtained.

 

First, the interphase of prefabricated parts with resin cured by a thermal initiator is characterized. Viscosity and gelation time of the resin are obtained by rheology experiments. The interdiffusion kinetics are determined by mass resin uptake tests. Hardness measurements are performed on the interphase by nano-indentations. By conducting differential scanning calorimetry (DSC) tests, the polymerization kinetics are obtained. Then, RLDM is used to print parts with TI.

 

The interphase thickness of resin with TI is compared to the casted samples of resin with PI. During casting the temperature evolution of the polymerizing is obtained by thermocouples. RLDM is used to print the resin with PI. The samples are used for obtaining the interphase thickness between the beads and laminas. Mechanical properties are obtained by performing three-point bending tests. Scanning electron microscopy (SEM) and optical microscopy are performed for obtaining the fractography at the cross-section.