[Structural changes in bronze (Gaudent) and Palliag alloys following corrosion effects]

Due to socio-economic considerations the use of two new types of non-oxydable alloys satisfactory for practical necessities should be examined more closely with a view to acquire a better knowledge of their behaviour. The present study investigates the behaviour of Gaudent and Palliag alloys under the effects of corroding agents. An analysis with an electronic micro-probe of the samples of ally exposed to corroding effects has evidenced various reactions in the buccal cavity and in the environment. In the buccal cavity the bronze alloy (Gaudent) has, in most of the cases, a satisfactory reaction from the macroscopical viewpoint. However, when exposed to hydrochloric acid and sodium hydroxide solutions it undergoes an intercrystalline corrosion and its surface aspect is changed. The Palliag alloy has an evident microscopic stability against these corroding agents.