Thermoplastic composite from innovative flat knitted 3D multi-layer spacer fabric using hybrid yarn and the study of 2D mechanical properties

Flat-knitted innovative three-dimensional spacer fabrics: a competitive solution for lightweight composite applications

“…The mechanical properties of the 2D surface and connecting fabrics (also in the formation of thermoplastic composites) of these multi-layer reinforced 3D spacer fabrics were investigated separately and the results were published accordingly. 6,7 These results clearly interpret the high performances of these multi-layered 3D spacer fabrics as textile preforms in composite applications.…”

“…In previous work, we reported the analysis and the manufacturing of 3D spacer fabrics on the basis of surface and connecting layers, 12 the development of 3D spacer fabrics possessing only the weft inlays [3][4][5] and the development of multi-layered 3D spacer fabrics. 7,8 The research work documented in this direction includes the basic production principles of some flat-knitted spacer fabrics without reinforcements 10 and the theoretical presentation of knitted sandwich spacer fabrics. 13 Nevertheless, the further developments of flat-knitted multi-layered 3D spacer fabrics including an increased number of reinforcement layers into all individual fabrics are essential for high mechanical performance in complex-shaped lightweight composite applications.…”

“…Furthermore, the flexibility of the knitting process in combination with the possibility of integration of reinforcement yarns into fabric structures is capturing the attention of many researchers. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] Moreover, knitted preforms exhibit greater drape-ability and higher impact resistance in composites as compared to the commonly used textile structures (e.g. braiding, weaving, unidirectional techniques).…”

“…The sensor networks realized into 3D spacer fabric structures by means of integrating the functional yarns during the single-step manufacturing of the multi-layered 3D spacer fabrics would be the break-through advancement in fully automated manufacturing of function-integrated textile preforms and such sensor networks could be used to monitor the structural perfection of end products. 7,8,10,[14][15][16][17][18] However, fibers, because of their aniosotropic mechanical properties and lower chemical and environmental resistances, cannot be used alone in structural engineering applications. They are, therefore, embedded in matrix materials to form fibrous composites.…”

“…This type of 3D spacer fabric with multi-layer reinforcements in the fabric structures is expected to show superior mechanical properties and be especially suitable as textile preforms for lightweight composite applications. [1][2][3][4][5][6][7][8][9][10][11][12][13][14] Future applications of composites made from 3D multi-layer spacer fabrics involve the replacement of conventional panel structures that are being used for aircraft, transport vehicles, marine applications and infrastructures, lift cabins, and ballistic protection for buildings and combat vehicles, etc.…”