Commentary on Anti-Tarnishing Experiment and Evaluation Method of Silver Alloy

Abstract: It is well known that silver alloy is prone to tarnish. The anti-tarnishing experiments can be taken to confirm a certain alloy's anti-tarnishing capability. There are two kinds of experiment methods, which are outdoors and laboratory experiments. Though the outdoors experiment could more really reflect alloy's anti-tarnishing capability under the certain environment, it need a long experimental time and has the lower reproducibility of the results. The laboratory experiment could be divided into two types, which are liquid experiment and gas experiment. The former includes the methods that the materials are soaped into corrosive solution like Na₂S solution, artificial sweat and salt water, etc, and the later includes H₂S experiment, SO₂ experiment and mixed atmosphere experiment. The common methods to evaluate alloy's anti-tarnishing capability include mainly naked eye observation, weighing weight, microcosmic analysis of corrosion film and spectrophotometer.