On the use of FBG sensors for measurement of curing strains in photocurable resins

摘要

Purpose - The objective of this study is to investigate the use of a fibre Bragg grating (FBG) sensor for measuring of curing strains that develop during the solidification of a photocurable resin used in 3D microfabrication. Design/methodology/approach - The followed approach consists of embedding a 1,300 nm FBG into a cylindrical specimen, fabricated into a transparent mould, being exposed to ultraviolet laser light. The further development of the cure induced strains under thermal treatment was also studied by post-conditioning the cylindrical specimen in an oven at 70℃. Findings - The experimental results demonstrate the capability of the FBG sensor to provide useful information on the strain build-up during laser solidification and their post-cure evolution under the presence of a thermal environment. Research limitations/implications - Future work should involve the use of smaller diameter FBG sensors in microstereolithography built parts. Practical implications - It is shown that considerable cure strains are developed at the end of the photo-polymerisation process that eventually can affect the structural resolution of final parts fabricated by microstereolithography. Originality/value - The presented method can be used to investigate other photopolymers used in micro-stereolithography.