VIBRATION MONITORING FOR IN-SITU HEALTH ASSESSMENT OF 3D PRINTED ABS POLYMER STRUCTURE UNDER THERMOMECHANICAL LOAD

Abstract

Acrylonitrile Butadiene Styrene (ABS) offers excellent mechanical properties that make it suitable for several industrial and aerospace applications. It is one of the most utilised materials in 3D printing/ Fused Deposition Modelling (FDM) which is widely growing. This thesis is investigating the dynamic response of non-prismatic fixed-free cantilever beam subjected to thermomechanical loads. The specimens are manufactured using 3D printing where crack depths vary from 0 to 2.5 mm with increment of 0.5 mm, and three different locations are introduced. The dynamic response is investigated using analytical, numerical and experimental approaches. A provided analytical model is used to prove the validity of the model for 3D printed ABS polymers under thermomechanical loads. The numerical simulation is used to find the natural frequency with respect to different crack depths and locations under thermomechanical loads. In the experiment, the loads are implemented by which the mechanical and thermal loads are applied using a shaker and heat mats, respectively. The crack propagation behaviour is monitored using 200x microscope, accelerometer and vibrometer. Accordingly, the findings are providing an in-situ damage assessment tool by establishing an empirical correlation to predict the crack depth as a function of dynamic response and applied temperatures.