IngentaConnect Inhibition by zinc1-hydroxyethylidene, 1,1-diphosphonic acid mixt...

Authors: Awad, H.S.; Turgoose, S.

Source: Corrosion Engineering, Science and Technology, Volume 38, Number 1, March 2003 , pp. 57-63(7)

Purchase options

The full text electronic article is available for purchase. You will be able to download the full text electronic article after payment.

$51.00 plus tax Refund Policy

More about this publication?

Authors wishing to cite fast track papers should give the journal name and the article DOI. This will enable reference linking via CrossRef and allow forward and backward citation tracking systems to associate the fast track citation with the final journal reference.
Editorial Board
Information for Authors
Subscribe to this Title
Terms & Conditions
Online submission site

Abstract:

The inhibition by a zinc-1-hydroxyethylidene, 1,1-diphosphonic acid (Zn-HEDP)mixture of the galvanic corrosion of mild steel coupled to copper with different cathode to anode area ratios has been investigated in neutral, aerated, chloride solutions. It was found that the Zn-HEDP mixture provides some inhibition of galvanic corrosion of mild steel, but only at relatively low area ratios of copper/steel (1 : 1 or less). However, this inhibition is significantly poorer than that provided for mild steel when not coupled to copper. At higher copper/steel area ratios (3 : 1 or greater) the Zn-HEDP mixture failed to show any inhibition of the galvanic corrosion of mild steel. This is considered to be due to an increase of the potential of mild steel to the pitting potential. Although the Zn-HEDP mixture is not capable of inhibiting the galvanic corrosion of mild steel coupled to copper at a 3 : 1 copper/steel area ratio or above, it provided good inhibition of the galvanic corrosion in the presence of benzotriazole (BTA). This inhibition is attributed to a significant reduction of the cathodic reaction on copper and of the anodic reaction of mild steel, i.e. it is due to a combined effect of both BTA and the Zn-HEDP mixture. It is believed that the former acts by blocking the copper surface, reducing the oxygen reduction reaction and hence allowing the Zn-HEDP mixture to inhibit the corrosion of mild steel.

Inhibition by zinc-1-hydroxyethylidene, 1,1-diphosphonic acid mixtures of galvanic corrosion of mild steel coupled to copper in dilute chloride solution and effect of benzotriazole