Thermal cure monitoring of UV curing resin with PVDF sensor

Abstract

SLA(Stereolithography) printing technology can achieve high precision and accuracy compared to other 3D printing methods. However, the single laser movement mechanism has the disadvantage of increasing processing time during the printing process and causing problems such as incomplete curing and premature gelation. In this study, we address these challenges by using acoustic emission (AE)-based detection of curing defects during the printing process in SLA, which utilizes UV-curable resin as its primary material. PVDF (Polyvinylidene Fluoride) sensors are used to detect AE during resin curing. Signals were analyzed based on the presence or absence of specific events to avoid signal ambiguity caused by internal voids during resin curing. Several AE parameters were evaluated experimentally. The most suitable parameters were identified for the detection of thermal cure signals. Among these parameters, AE RMS and AE Count showed the most significant variations in response to thermal curing signals. The proposed method can be used for smart monitoring in SLA printing to detect defects, such as incomplete curing, early in the process, contributing to precision manufacturing. © 2024 SPIE.