Sensitivity Analysis and Multi-Objective Optimization Strategy of the Curing Profile for Autoclave Processed Thick Composite Laminates

Abstract

To mitigate the risk of manufacturing defects and improve the efficiency of the autoclave-processed thick composite component curing process, parameter sensitivity analysis and optimization of the curing profile were conducted using a finite element model, Sobol sensitivity analysis, and the multi-objective optimization method. The FE model based on the heat transfer and cure kinetics modules was developed by the user subroutine in ABAQUS and validated by experimental data. The effects of thickness, stacking sequence, and mold material on the maximum temperature (Tmax), temperature gradient (ΔT), and degree of curing (DoC) were discussed. Next, parameter sensitivity was tested to identify critical curing process parameters that have significant effects on Tmax, DoC, and curing time cycle (tcycle). A multi-objective optimization strategy was developed by combining the optimal Latin hypercube sampling, radial basis function (RBF), and non-dominated sorting genetic algorithm-II (NSGA-II) methods. The results showed that the established FE model could predict the temperature profile and DoC profile accurately. Tmax always occurred in the mid-point regardless of laminate thickness; the Tmax and ΔT increased non-linearly with the increasing laminate thickness; but the DoC was affected slightly by the laminate thickness. The stacking sequence has little influence on the Tmax, ΔT, and DoC of laminate. The mold material mainly affected the uniformity of the temperature field. The ΔT of aluminum mold was the highest, followed by copper mold and invar steel mold. Tmax and tcycle were mainly affected by the dwell temperature T2, and DoC was mainly affected by dwell time dt1 and dwell temperature T1. The multi-objective optimized curing profile could reduce the Tmax and tcycle by 2.2% and 16.1%, respectively, and maintain the maximum DoC at 0.91. This work provides guidance on the practical design of cure profiles for thick composite parts.

Global Sensitivity Analysis of Factors Influencing the Surface Temperature of Mold during Autoclave Processing

“…This paper applies the Sobol method to conduct a detailed global sensitivity analysis (GSA), aiming to quantify the individual effects of each factor and their interactions with other factors on the variation in the mold surface temperature during the autoclave processing. In this method, the variance-based sensitivity indices provide a scalar measure of relative influence based on conditional variance, which is widely recommended by researchers [ 16 , 17 , 18 , 19 , 20 ] for effectively characterizing single- and multi-parameter interactive sensitivities in non-linear and non-additive models, and the relatively straight forward interpretation of the sensitivity indices. There are five factors considered in this analysis including CHTC, TCL, TMF, MMT, and TAL used in the autoclave processing.…”

Advancements in Functionally Graded Polyether Ether Ketone Components: Design, Manufacturing, and Characterisation Using a Modified 3D Printer

“…The combination of traditional manufacturing methods for polymers and composites with additive manufacturing has revolutionised the production landscape. Traditional manufacturing processes such as hand lay-up, vacuum assisted resin transfer moulding, injection moulding, autoclave, extrusion, and compression moulding have long been employed for large-scale fabrication of polymers and composites parts [ 1 , 2 , 3 ]. These methods offer high production rates, precise control over material properties, and cost-effective solutions.…”