Corrosion Between a Graphite/Polymer Composite and Metals

Abstract

A graphite/polymer composite material was directly coupled with: 2014 aluminum (bare and hard-anodized), pure grade titanium, 316 stainless steel and monel. Samples were then immersed in natural seawater. The titanium couple was inactive. Stainless steel and monel changed behavior from noncorroding to crevice and pitting corrosion. Corrosion behavior of 2014 aluminum was not changed by the couple. However, blistering occurred on the composite when active corrosion of aluminum occurred. Crystal growth was observed on the composite when coupled with aluminum and with stainless steel.

Corrosive delamination processes of CFRP‐aluminum alloy hybrid components

“…By the formation of hydroxide ions (OH − ) at the interface cathode/electrolyte a local increase of the pH value is noticeable. According to Ref., [12] the diffusion of this species into the composite is likely the cause of the observed blistering.…”

“…Comparable studies are presented in Refs. [12,23,25] The development of the pH value as a result of the local cathodic reaction was monitored on a CFRP-aluminum hybrid specimen. After 2 min an alkalization in the overlap FIGURE 5 Visual changes of the CFRP surface in the overlap region FIGURE 6 Breaking/buckling of the glass fibers (left) and debonding between the glass fibers and the epoxy matrix (right) as observed by FIB FE-SEM area could be observed (pink coloring of the indicator phenolphthalein).…”

“…The rise of the pH value due to the cathodic reaction on composite is also reported in the literature. [10,12,15,24,26,27] The cathodic reaction on CFRP (Figure 8b) causes chemical changes within neutral solutions. By the formation of hydroxide ions (OH − ) at the interface cathode/electrolyte a local increase of the pH value is noticeable.…”

“…The contact of exposed carbon fibers with metallic materials, inter alia by connection technology in form of bolts, screws or rivets, results in the presence of an aqueous solution to contact corrosion. [10][11][12][13][14] The four essential components of a wet corrosion cell are anode, cathode, electrolyte, and electrical conducting connection. The corrosion of the metal takes place at the anode.…”

Galvanic corrosion behavior of NiC filled conductive silicone rubber coupled to AZ31 magnesium alloys

“…Meanwhile, the researches on the corrosion of conductive polymer materials are focused on the anti-corrosion coating [34][35][36][37][38]. Only few studies [39] are reported about the galvanic corrosion behavior of conductive polymer materials coupled to metal materials.…”