Elsevier

Materials & Design

Volume 30, Issue 3, March 2009, Pages 867-870
Materials & Design

Short Communication
Tensile behaviours of quartz, aramid and glass filaments after NaCl treatment

https://doi.org/10.1016/j.matdes.2008.05.055Get rights and content

Abstract

Quartz, aramid and glass filaments were treated with NaCl solutions of various concentrations for different periods of time. The appearance of the treated filaments was examined. It revealed that for the quartz fibre the NaCl density and the treatment time have a minor effect as far as the decrease rate of the fibre strength is concerned. After three weeks of NaCl treatment, dramatic degradation of the aramid filaments was noticed for all the NaCl densities used in the investigation. The glass fibre degradation induced by the NaCl solution was considered regular; both higher NaCl concentration and prolonged treating time would both promote the decrease of the fibre strength.

Introduction

High performance filaments are frequently used as the reinforcements of composites. The important properties contributing to this situation are their high strength-to-weight ratio. The corrosion resistance of the composites is one of the main reasons for the expenditure of the research on these materials. One of the major corrosive conditions is considered to be the NaCl environment. NaCl corrosion has been a major concern for industries such as chemical, oil, marine and electricity. Composites are often used in marine boats, vessels, ships, and offshore drilling platforms for deck grates. These items may be attacked by seawater [1], [2]. Pipes and tubes used to conduct liquid would come in contact with chemicals in which NaCl may be involved. One of the obstacles preventing the extensive use of composites has been a lack of long-term durability and performance data [3]. It is necessary to understand how the materials will behave during service in a critical environment [4].

Fabricated composites were frequently involved in the investigation of the behaviours of the reinforcement filaments in which case the fibres were mixed with the matrix [5], [6], [7], [8]. In such a situation the degradation of the filaments mostly depends on the resin’s corrosion resistance [5], [6], and the crack propagation of the material in the critical environment is also related to the resin toughness [5]. It is indicated that after a prolonged service in a corrosive environment, damage of materials would result [7]. Since filaments are enclosed by the matrices in the composites, the understanding of the basic mechanisms of the damage and degradation of the fibre would be uncertain. On the other hand, many investigations have been focused on the glass fibre reinforced products in this field [5], [6], [7], [8], [9], [10], [11], very little work has been done on the quartz, aramid, and glass filaments.

Quartz, aramid, and glass filaments were treated with NaCl solutions of various densities for different periods of time. Tensile strength comparison between the NaCl-treated and -untreated filaments revealed that degradation of the treated fibres occured. The tensile strength change among the filaments tested showed a different trend. The appearance of the NaCl-treated filaments was also examined, which indicated the corrosion of NaCl on the fibres.

The main objective of the research is to study the immediate effect of NaCl on quartz, aramid, and glass fibres, expecting to exclude the influence of the matrix and reveal the direct response of the fibres to the NaCl environment.

Section snippets

Experimental

Quartz filament with a linear density of 0.1617 tex (QS-2002-29, provided by Jingzhou Quartz and Glass Factory, PR China), Aramid filament with a linear density of 0.2467 tex (Kevlar Type 49, manufactured by Du Pont Toray Co., Ltd.), and glass filament with a linear density of 0.2292 tex (Type E, produced by Tianjin Glass Fibre Company, PR China) were treated with NaCl solutions with densities of 2%, 5%, 7%, and 10%, respectively. The length of the filaments used in the investigation was 50 mm.

Quartz filament

The fineness of the quartz fibre employed in the research is 0.1617 tex, and the average fibre strength is 17.1cN.

Fig. 1 shows the tensile strength of the quartz fibre after the NaCl treatment. Since four concentrations (2%, 5%, 7%, and 10%) of the NaCl solution were adopted, and for each concentration, four different time periods (one to four weeks) were employed, altogether there were 16 groups of samples. Each datum in the figure is the average of five determinations.

From Fig. 1 one may

Conclusion

The research presents a thorough understanding of the response of the quartz, aramid, and glass fibres to the NaCl solutions excluding the involvement of the matrix. NaCl is powerful enough to break the molecular chain and the bond between two elements in some compounds. Deterioration of quartz, aramid, and glass fibres occurs if they come in contact with NaCl; prolonged exposure to NaCl and higher concentration of the NaCl solution would decrease the tensile strength of the filaments greatly.

Acknowledgement

This work is financed by the Key Laboratory of China Education Ministry, Zhejiang University of Sciences under the project “Research on ageing behaviours of composites in moisture environments”, No. 2005003.

Cited by (25)

  • Crystal-pit-cracking formation on composite modified slag fiber in long-term water immersion

    2019, Journal of Non-Crystalline Solids
    Citation Excerpt :

    Previous studies have reported the factors affecting the corrosion of slag fibers. However, these have mainly focused on alkaline or acidic environments, glass fiber, and basalt fiber [8,9]. The acid resistance of basalt fiber is much higher than its alkaline resistance, while the opposite is true for slag fiber; the acid resistance and alkaline resistance of glass fiber are similar [10].

  • Dissolution behavior of a novel composite fiber made from blast furnace slag

    2019, Construction and Building Materials
    Citation Excerpt :

    When slag fibers were used in exposed materials of equipment and piping [11], they were inevitably subjected to severe environmental corrosion, especially under acidic and alkaline conditions. Glass and basalt fiber were tolerant to some extent to alkaline or acidic media [12,13]. The hydrolysis of glass fibers depends on the silicate network, during which Ca can be an aggressive alternative to the local charge of 4-coordinated aluminum [14].

  • Surface modification of hybrid-fabric composites with amino silane and polydopamine for enhanced mechanical and tribological behaviors

    2017, Tribology International
    Citation Excerpt :

    One means to overcome this limitation is to modify the surfaces of hybrid Nomex/PTFE fabric to improve fabric/resin interfacial adhesion, which generally leads to concomitant increase in mechanical and tribological properties of the polymer composites. So far, considerable methods have been utilized to modify the surfaces of aramid fibers, including ultrasonic treatment [5], ultraviolet radiation [6], plasma treatment [7], γ-ray irradiation [8], chemical etching and grafting [9–11]. Although most aforementioned fiber treatment methods can endorse the increases in aramid fibers/matrix adhesion to enhance composites utility, these approaches are generally restricted by high cost instruments, drastic reaction conditions and loss in fiber strength.

View all citing articles on Scopus
View full text