Gamry FlexCell, Руководство оператора

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Chapter 1: Introduction--Checking for Shipping Damage
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Chapter 1: Introduction
The Flexcell is used to perform electrochemical tests on flat metal specimens. Unlike traditional cells, the
crevice-free cell avoids localized corrosion at the seal between the sample and its holder. Following a design
popularized by Avesta Steel, the cell uses a flooded-gasket seal. This simple, yet elegant, design results in an
easy-to-use, reliable, crevice-free system.
Figure 1 is an expanded, cross-sectional diagram of the cell in the area of the flooded seal.
Figure 1
Cross-section of the Flooded Seal
As in conventional cells, the active area of the test specimen is in contact with an electrolyte. Unlike other cells,
the active area of the test specimen is not bounded by a plastic barrier or O-ring.
De-ionized water is slowly forced through a fiber washer placed on the test-solution-side of the metal sample
being tested. After passing through the washer, the water diffuses into the electrolyte. The fluid in the fiber
washer is nearly pure deionized water, which is not conductive enough to support corrosion processes. Thus,
instead of a plastic barrier with its resultant crevice, a conductivity gradient between the electrolyte and the
deionized water defines the test specimen
’ s active area.
The Flexcell components were selected to be as chemically inert as possible. In normal use, the only materials
in contact with the test solution are glass, filter paper, and PTFE. The cell is therefore usable with a wide variety
of test solutions, including non-aqueous media.