Investigation of the friction behavior between dry/infiltrated glass fiber fabric and metal sheet during deep drawing of fiber metal laminates

Abstract

During deep drawing processes of fiber metal laminates, such as the newly developed in-situ hybridization process, fibers and metal sheets come into contact while the dry fabric is infiltrated by a reactive matrix system. The viscosity of the matrix increases as polymerization starts during deep-drawing. In the in-situ hybridization process, a dry fiber metal laminate is deep drawn while a thermoplastic matrix system is injected into the glass fiber fabric layer in a resin transfer molding process. During forming of the fiber metal laminate, friction occurs in tangential direction to the metal sheet. The friction plays the main role in preventing the elongation of the sheets in the deep drawing process. Therefore, the measurement of friction coefficients between fibers and metal sheets is essential. In this paper, the friction between sheet metal and dry or infiltrated glass fiber fabric under high contact pressures of 1.67 MPa, as occurring in deep drawing processes, is characterized. A modified strip drawing test setup is used to analyze the coefficient of friction under a constant high contact pressure. Compression tests were performed to show that Coulomb friction can be assumed. Different types of glass fiber fabrics and liquids with defined viscosities are used. It was found that fluids with higher viscosity decrease the friction coefficients in the interface, which is physically explained. For the in-situ hybridization process, it is deduced that with low viscosities, a better infiltration is achieved, while higher viscosities reduce the friction coefficient for better formability.

Permeability and fabric compaction in forming of fiber metal laminates

“…Different friction coefficients from literature are used to contribute to the three contact pairs (μ Tool-Metal = 0.2, μ MetalPly = 0.253, μ Ply-Ply = 0.334). 55 The model and its submodels have already been validated concerning predicted reaction forces for the pure Figure 9. Illustration of the intra-ply modeling approach for each of the single textile layers within the stack, combining a continuum shell (SC) element and a superimposed user element in ABAQUS based on.…”

“…Different friction coefficients from literature are used to contribute to the three contact pairs ( μ Tool-Metal = 0.2, μ MetalPly = 0.253, μ Ply-Ply = 0.334). 55…”

Modeling of 3D fluid-structure-interaction during in-situ hybridization of double-curved fiber-metal-laminates

“…4. In the case of dry friction (solid contact), coulomb friction is modeled using coefficients of friction (CoF) that have been identified by Kruse et al [24] (𝜇𝜇 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇,𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑀𝑇𝑇 = 0.2, 𝜇𝜇 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇,𝑇𝑇𝑀𝑀𝑇𝑇𝑀𝑀𝑇𝑇𝑇𝑇𝑀𝑀 = 0.253, 𝜇𝜇 𝑇𝑇𝑀𝑀𝑇𝑇𝑀𝑀𝑇𝑇𝑇𝑇𝑀𝑀,𝑇𝑇𝑀𝑀𝑇𝑇𝑀𝑀𝑇𝑇𝑇𝑇𝑀𝑀 = = 0.334). Due to the metal sheet, high contact stresses of 2000 N/mm 2 are necessary to prevent excessive contact penetration.…”

Experimental investigation of the fluid-structure interaction during deep drawing of fiber metal laminates in the in-situ hybridization process

“…Due to the low matrix viscosity, fibers and metal are in direct contact during the forming process. While a low-viscosity matrix is advantageous for fluid flow and fabric drapability during forming, friction between metal and fabric is higher because of high local normal loads at the roving crossings [12]. Previous investigations have shown that this contact under high normal pressures can reduce the formability of the metal sheet by restricting relative movement between fibers and metal [13].…”