Influence of the Gastrointestinal Environment on the Corrosion Mechanism of a Biodegradable Zn–0.4li Alloy

Abstract

The corrosion behaviours of Zn–0.4Li in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) were investigated. Compared with samples in SIF, those in SGF were severely corroded locally. Pepsin and pancreatin participated in the formation of degradation products. After immersion in SGF and SIF, the corrosion process presented three stages. Lithium (Li) reacted in the passive region. The solution penetrated the oxide layer to further corrode Li in the active region, resulting in a Li-poor region. As the Li ions diffused, they adhered to the oxide layer and formed a Li-rich region between the passive and active regions.

Keywords: Zinc, gastrointestinal environment, corrosion mechanism