Mechanical characterisation of the shear, bending and friction behaviour of bindered woven fabrics during the forming process

Abstract

A critical process step within the liquid composite moulding constitutes in the preforming of two‐dimensional textile material into a near‐net‐shape and load‐capable fibre structure by stamp forming. This paper presents fundamental material experiments on the shearing behaviour, bending properties and friction behaviour considering the binder quantity and forming temperature. In addition, the influence of the process time on the resulting stability of the preform is examined. The findings indicate that the quantity of the binder as well as the forming temperature and the process time have a great influence on the preform quality.

Spray binder for automated preforming: Spray process and preform properties

“…At 105 C and above, the swirl fiber starts breaking and forming drops, leading to an uneven spray pattern. This observation is consistent with the data sheet of CeTePox AM1010 [45] which recommends temperatures between 90 and 95 C for a uniform swirl spray application and observations of Marla et al [46] A possible explanation for the knots is given in Formoso et al [45]. It was shown that increasing the ratio between spray airflow and material flow increases the risk of the swirl making contact with itself and forming knots.…”

“…After releasing the flexural force, the samples stay in their deformed shape but slowly return to their initial state. The measured flexural modulus is also lower than the ones found in Dickert [24] and Coutandin et al [46] for powder binders, while the flexural stress reaches similar values when using a test speed of 60 mm/min. In both publications, the initial flexural modulus of the plain textile without binder is already higher (50 MPa for Dickert and 380 MPa for Coutandin et al) making it difficult to directly compare the results.…”

“…He found a linear growth of flexural modulus and stress for rising binder grammage. Coutandin et al [46] found a linear increase in flexural modulus for rising binder grammage, as well. This does not apply to the spray binder tested in this publication.…”

Numerical modeling of fiber reinforced polymer textile composites for characterizing the mechanical behavior – a review

“…The cantilever bending test of woven fabric composite was performed at different forming temperatures. The forming temperature has no significant influence on the bending modulus of the composite [114].…”

Binders Used for the Manufacturing of Composite Materials by Liquid Composite Molding

“…The mechanical behavior of bindered (EPIKOTE Resin 0539) and dry woven fabrics (SIGRATEX C W305-PL1/1), which has been examined under consideration of the forming temperature [ 86 ], showed, that binder quantity and forming temperature have a substantial impact on the in-plane shear behavior. When temperatures dropped, the impact of the binder and activation time increased.…”