Experimental Study on Bi-Axial Mechanical Properties of Warp-knitted Meshes with and without Initial Notches

Abstract

Warp-knitted meshes have been widely used for structural reinforcement of rigid, semi-rigid, and flexible composite materials. In order to meet the performance requirements of different engineering applications, four typical warp-knitted meshes (rectangular, square, circular, and diamond) were designed and developed. The mechanical behaviors of these meshes under mono-axial and multi-axial tensile loads were compared. The influence of the initial notch length and orientation on the mechanical performance was also analyzed. The results showed that the biaxial tensile behavior of warp-knitted meshes tended to be more isotropic. The anisotropy level of the diamond warp-knitted mesh was the lowest (λ = 0.099), while the rectangular one was the highest (λ = 0.502). The notch on a significantly anisotropic mesh was propagated along the direction of larger modulus, while for a not remarkably anisotropic mesh, notch propagation was probably consistent with the initial notch orientation. The breaking strength of warp-knitted meshes with the same initial notch orientation decreased with the increase in notch length in both the wale and course directions. For warp-knitted meshes with the same initial notch length, the breaking strength in the wale direction was kept stable at different notch orientations, while that in the course direction decreased remarkably with notch orientation from 0° to 90°.

Review on the performances and applications of mesh-fabrics

“…Uniaxial tensile test is used widely, usually the sample size and loading rate are slightly different. 25,26 Yang et al studied the mechanical properties of the protective nets with different polyethylene monofilament diameters and knitting densities, including tensile stress along with the fabric in three directions with 0°, 45°and 90°. 27 The results indicated that several kinds of protective mesh show good mechanical properties.…”

Mechanical properties of warp-knitted metal mesh fabric under biaxial tension loading

“…The current research on the biaxial or multiaxial mechanical properties of materials generally focuses on composite materials with woven fabrics as reinforcements and films. Shao et al 14 and Bigaud et al 15 proposed the biaxial constitutive relationship of composite materials with woven fabric as the reinforcing material and a new failure criterion. Chen et al 16,17 focused on the tear analysis of typical airship hull materials.…”

“…The research on the mechanical properties of warpknitted fabrics mostly focuses on tensile mechanical properties, tearing properties and the influence of notches on mechanical properties. 7,14,[18][19][20] Research on biaxial stretching is rarer, with no mention of metal mesh. At present, most researches on metal meshes concentrate on the electrical performance of large retractable satellite antennas, such as the work of Li et al 12 and Shao et al, 21 who researched the application of metal mesh to satellite antennas, studied the influence of its coating, structure and other factors on its electrical performance, and used derived analysis methods such as the equivalent regular grid unit of the strip model.…”

“…Shao et al. 14 and Bigaud et al. 15 proposed the biaxial constitutive relationship of composite materials with woven fabric as the reinforcing material and a new failure criterion.…”

“…The research on the mechanical properties of warp-knitted fabrics mostly focuses on tensile mechanical properties, tearing properties and the influence of notches on mechanical properties. 7,14,18–20 Research on biaxial stretching is rarer, with no mention of metal mesh. At present, most researches on metal meshes concentrate on the electrical performance of large retractable satellite antennas, such as the work of Li et al.…”