Experimental study on uniaxial tensile and welding performance of a new coated fabric for airship envelopes

Abstract

This paper investigated the mechanical properties of GQ-6 subjected to a tremendous amount of uniaxial tests. Such material is a new kind of ultra high molecular weight polyethylene fiber and aimed to be adopted in stratospheric airship. To begin with, mono-uniaxial tensile tests were conducted. The cycling-uniaxial tensile experiments were then carried out on the basis of the mono-uniaxial tensile tests data. Finally, performances of welding seams were thoroughly investigated with forty welding specimens. Results of mono-uniaxial tensile tests revealed that such woven fabric possesses high tensile strength and low elongation ratio at break. Meanwhile, the stress–strain behaviors were fitted by the Ogden model and a good agreement between such model and experimental data was obtained. Influences of the uniaxial loading cycle on such woven stiffness were discussed and the elastic moduli were defined with a standard hysteresis loop. For the welding tests, four types of overlapping welding failures were discovered. Compared with intact specimens, an appropriate welding width of 60 mm and an approximate 15% discount of the ultimate tensile stress on the intact textile were obtained.

Experimental investigation and theoretical analysis of tear propagation of GQ-6 airship envelope

“…According to our previous paper [2], the yarns applied in the warp and weft direction of GQ-6 are the same. However, the mechanical property of the warp yarns will be of more strength than that of the weft yarns due to the particular knitting technology.…”

“…The constitutive relationship and the ultimate tensile stress of the GQ-6 have been studied [2] on our previous uniaxial tensile work. Some of its specifications are listed in Table 1.…”

“…To obtain a homogeneous tensile stress in the central square, three slits were cut to divide each arm into four 40 mm wide strips. The clamped area was reinforced with an aluminum sheet [2] to prevent failure occurring in the clamped region prior to the central area tearing. The corner between adjacent arms was rounded with a radius of 10 mm in order to minimize stress concentration.…”

“…Recently, a new kind of textile GQ-6 has been invented by 46th Research Institute, 6th Academy of China Aerospace Science & Industry Corp, especially used for the envelope material of airship. The basic mechanical properties of GQ-6 have been generally studied [2]. However, to avoid the catastrophic failure caused by crack propagation, the fracture resistance strength of GQ-6 still calls for full understanding.…”

Investigation of the tearing properties of a new airship envelope fabric based on experimental and theoretical methods

“…There has been an increasing interest in stratospheric airship [1] as an alternative to traditional air vehicles for telecommunication and science observation. As one of a significant structural part in an airship, it is major developments in membrane materials [2][3][4] that have been uniquely responsible for advances in airship design. In the real engineering application, the initial crack or defect expansion of the envelope material easily causes the whole airship to tear and damage quickly under the stratosphere environment.…”