Investigation of interfacial debonding between steel wire and adhesive resin

Abstract

Plastic pipes reinforced by cross helically wound steel wire (PSPs) have been widely used in the transportation of petroleum, natural gas, municipal water, and so on. With the applications of PSPs in high-temperature and high-pressure environments, the problem of PSP joints has begun to appear. The bulging failure of PSP joints is the main failure mode, and steel-polymer interfacial debonding is the major factor causing bulging failure. Thus, it is crucial to understand the failure criterion of steel-polymer interfacial debonding. In this study, pull-out tests were carried out at different temperatures and loading rates. A finite element (FE) model was developed on the basis of the cohesive element. We proposed that the key parameter for the bugling failure of PSPs was the shear stress of the steel-polymer interface. We assumed that when the shear stress exceeded the shear strength, this led to the degradation of the interface. By iteratively presetting the shear strength and calculation of the FE model, the FE results were verified with experimental results. We found that the shear stress of the front part of the FE model first reached its peak value; its interface began to degrade, and then, the shear stress decreased. The peak value of the shear stress moved toward the end part of the FE model, and the shear strength could be obtained. Finally, the effects of the temperature and failure time on the shear strength were investigated.

Measurement of Adhesion of Sternal Wires to a Novel Bioactive Glass-Based Adhesive

“…After the required incubation time, pull-out tests were performed using a tensile testing system with a load cell of 5 kN and an accuracy of ±0.15 N (United Testing Systems Inc., Fullerton, CA, USA). As in previous studies that have utilized pull-out tests to assess adhesion between steel wires and adhesive resin [47], displacement rates of 1, 0.1, and 0.01 mm/min were used. The setup used for the pull-out test (shown in Figure 3) is similar to that previously used in [48,49] to test the adhesion of orthodontic adhesives to wires and to study the tensile and fracture properties of acrylic bone cements reinforced with both silane-coated and uncoated 316L stainless steel fibers.…”