Fluorinated nana-fibres and corrosion

Title: Fluorinated nana-fibres and corrosion
Author(s): P. van Tonder, D. Kruger, B. Jones
Paper category : conference
Book title: 2nd International Symposium on Service Life Design for Infrastructures
Editor(s): K. van Breugel, Guang Ye, Yong Yuan
Print-ISBN: 978-2-35158-096-7
e-ISBN: 978-2-35158-097-4
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 655 - 662
Total Pages: 8
Nb references: 6
Language: English

Abstract: It was investigated whether the addition of fluorinated (15 seconds fluorination) nanofibres (carbon nanotubes and graphite fibres) were favourable in preventing corrosion of reinforcing steel embedded within the concrete. Concrete samples cast either did not contain any nanofibres, contained graphite nanofibres / multiwall carbon nanotubes mixed into the concrete or nanofibres placed as closely as possible to the steel within the specimens. Sodium chloride was added to the concrete to simulate one of the conditions under which corrosion occurs. After 99 days, the concrete samples were fractured and the steel removed in order to determine the corrosion rates using the gravimetric (mass loss) method.
Fluorinated nanofibres had an increased effect on the corrosion rates of the steel specimens, particularly when the nanotubes were used and even more so when the nanotubes were placed as closely as possible to the steel reinforcement. The fluoride ion within the fluorinated nanofibres increased the corrosion rate of the steel specimens. This suggests the concentration of the fluoride ion was low i.e. less than 25 parts per million (ppm). Another conclusion which may be drawn is that a fluorination time of 15 seconds (as used is this project investigation) produces low concentrations of the fluoride ion. If the fluoride ion concentration of the fluorinated nanofibres can be increased, it may create an environment within steel reinforced concrete for the prevention of corrosion.

Online publication: 2011-04-20
Publication type : full_text
Public price (Euros): 0.00