Compensation of process‐induced deformations of double‐curved carbon–epoxy composite elements

Under the influence of extrinsic curing conditions and intrinsic properties of carbon fiber reinforced resin composites, the formation of curing deformation is inevitable, which makes the shape of the manufactured components differ from the designed structure, and even exceeds the assembly tolerance, resulting in the scrap of parts. Therefore, it is very urgent and important to optimize the curing deformation of carbon fiber reinforced resin composites. In this paper, the mechanism of stress and curing deformation is reviewed firstly, and then the factors affecting the curing deformation are summarized. In particular, from the point of view of materials in curing process, three curing deformation control strategies, including (i) reinforcement structure optimization, (ii) resin modification and process optimization, (iii) die surface compensation and tool‐part contact optimization, were proposed. And with the development of curing deformation simulation technology, the (iv) inverse design strategy before curing and (v) hot sizing method from the view of after cured were further put forward, respectively. By analyzing the link between processing details and curing deformation, it is found that the dominant factor affecting deformation may change under different conditions, so the interaction between factors needs to be further discussed. Subsequently, the effect of these distortion control methods on curing deformation was analyzed and evaluated, and the shortcomings were pointed out. Finally, the challenges existed in curing deformation research were identified, in order to contribute to the development of curing deformation research.

Section: Deformation Control Strategies and Methodsmentioning

confidence: 99%

Section: Deformation Control Strategies and Methodsmentioning

confidence: 99%

Review of curing deformation control methods for carbon fiber reinforced resin composites

Zhang

et al. 2022

“…For composites with the same material system, curing process, and surface treatment, the mold-part interaction relationship can be considered to be the same. 8,11 Since this article assumes that the interaction layer parameters are only related to the fiber orientation of the layup fabric in contact with the mold and ignores the interactions of the intermediate layups, the shear layer model established in this article can predict the warpage deformation of the layup composite with 0 layup on both the upper and lower surfaces. Therefore, in this section, [0/90/90/0] and [0/45/45/0] laminated composites are studied to verify the correctness of the model interaction parameters by comparing the simulated and experimental warpage deformation.…”

Section: Model Validationmentioning

confidence: 99%

“…In addition, Zhang et al 10 also reviewed that the stretching effect of the mold surface on the fabricated part is an important factor affecting the warpage of the plate in the curing process. And Galinska et al 11 believed that if the tool is not manufactured from the carbon–epoxy composite material, its thermal expansion is a significant factor that causes additional deformations.…”

Section: Introductionmentioning

confidence: 99%

Effect of mold on curing deformation of resin transfer molding‐made textile composites

Zhang

Sun

et al. 2023

In the process of preparing textile composites by resin transfer molding (RTM) method, both the upper and lower surface of the mold will interact with the composite parts due to the mismatch of thermal expansion coefficient between the mold and the part, resulting in warpage deformation. To address this key technical problem, this article first studied the effect of mold on the warpage deformation of composite material under different fiber volume fractions. Then a mold–part interaction modeling method for RTM process with nonthermoelastic deformation is proposed. By introducing shear layers between the upper and lower surfaces of the mold and the composite part, a finite element simulation model for predicting the curing deformation of the component is established and experimentally verified. The results show that the effect of mold–part interaction on the warpage deformation of the composite decreases with increasing fiber volume fraction. Meanwhile, the proposed modeling method can avoid complete material characterization, and the comparison between experimental and simulation results proves that the model can accurately simulate the curing deformation of composite components under the same process conditions. Finally, the analysis reveals that the interaction caused by thermal mismatch between the composites and the mold is less related to the intermediate layup, but mainly related to the fiber orientation of the layup layer in contact with the mold.Highlights The warpage deformation law of the mold on the composites with different fiber volume fractions is investigated. A mold–part interaction modeling method for a resin transfer molding process with nonthermoelastic deformation is proposed, where the mold stretching effect is represented by the cumulative effect of the interaction between the two layers on the upper and lower surfaces of the part.

“…Their utilization in modern vehicles, buildings, and airplanes is growing rapidly. [1][2][3][4][5] A significant characteristic of composite parts in the manufacturing process is the unavoidable cure-induced deformation. The deformation form of composite parts mainly includes two types: spring-in and warping.…”

Section: Introductionmentioning

confidence: 99%

Bi‐stable cured shape of CFRP variant structures with asymmetric layup: Rapid prediction and inverse design

Sun,

Liu,

Zhao

et al. 2024

This study aims to produce variant composite structures that can precisely maintain equilibrium after changing stable states. A rapid and precise prediction method for the cure‐induced bi‐stable warping was developed, and the inverse design for the required part's structural and material parameters was investigated. Firstly, the mechanism causing the warping was investigated. Then, in order to acquire basic data for a data‐driven model to achieve rapid and accurate warping prediction, a finite element analysis (FEA) was developed, with most of the prediction deviations being under 10%. Additionally, deformation forms of variant parts with various layups and shapes were studied to offer guidance for the different shape requirements. The structural and material parameters were analyzed using the response surface methodology and sensitivity analysis. After removing parameters like all rubbery properties with low influence, basic data from the parameterized FEA was utilized to build a precise proxy model. Finally, for the variant structures requiring reasonable shape forms, the inverse design of the material, layup, and sizes can be achieved using the proxy model and the non‐dominated sorting genetic algorithm II. All optimization results were validated using FEA or experiments. The deformation form in the two steady states of each case meets the specifications. The shape difference between the produced part and the required shape is less than 5 mm, and the design deviation for the maximum deformation is less than 10%. Consequently, the rapid prediction and inverse design methods for the bi‐stable shape of variant composite parts were effective and accurate.Highlights All the rubbery properties are almost uncorrelated to the bi‐stable warping. The proxy model can rapidly and precisely predict the bi‐stable shape. The inverse design can be achieved for a part requiring proper bi‐stable shapes. The design part can precisely maintain equilibrium with the required shapes.