Establishing a quantifiable tarnish timeline for comparison of anti‐tarnish processes in metals. Issue 10 (9th February 2015)

• Record Type: Journal Article
• Authors: Yousef, H.N.S.; Cobley, R.J.; Davies, H.M.; James, D.M.; Mehmood, S.; Sackett, E.; Sienz, J.
• Is Part Of: Materials and corrosion. Volume 66:Issue 10(2015:Oct.)
• Page Start: 1120
• Page End: 1124
• Publication Date: 2015-02-09
• Subjects: Materials -- Periodicals; Metals -- Periodicals; Corrosion and anti-corrosives -- Periodicals; 620.1122305
• DOI: 10.1002/maco.201407969
• Languages: English
• ISSNs: 0947-5117

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="maco201407969-sec-0001" sec-type="section"> <p>Brass samples were controllably tarnished using the thioacetamide accelerated corrosion (ISO 4538:1995) and synthetic sweat (ISO 3160–2:2003) methods. Spectrophotometry, energy dispersive X‐ray spectroscopy (EDX) and electrochemical impedance spectroscopy (EIS) were performed on samples tarnished for set exposure times over seven days. Synthetic sweat produced a loose surface corrosion layer, which limited the use of EIS and spectrophotometry, but for the thioacetamide method both measurements produced a continuous change over the time period. EDX was able to observe a continuous change in the surface layer chemistry for both methods over the whole timescale and represents the best characterisation method to establish an equivalent tarnish timeline against which anti‐tarnish treated samples can be compared. The current study was conducted using brass, however the method can be used for quantifying tarnish on other metallic systems.</p> </sec> </abstract>