Work

Effect of Calcium Nitrate on Microstructure and Anti-Corrosion Properties of Zinc Phosphate Coatings on Stainless Steel

Year: 2025

Type: article

Abstract: Hopeite (Zn3(PO4)2·4H2O) coatings, fabricated via zinc phosphate chemical conversion (ZPCC), have attracted considerable interest in biomedical applications owing to their excellent corrosion resistance and biocompatibility. However, the influence of calcium nitrate (CN) on coating properties remains poorly understood. This study systematically investigates the effect of CN concentration on the microstructure and corrosion behavior of ZPCC coatings deposited on stainless steel (SS). The phase composition, surface morphology, and elemental distribution were characterized using X-ray diffraction (XRD) and scanning electron microscopy with energy-dispersive spectroscopy (SEM-EDS). Electrochemical corrosion performance was assessed via potentiodynamic polarization in a 0.9 wt.% NaCl solution. The results indicate that CN concentration critically influences coating morphology, with higher concentrations leading to reduced crystal size and increased coating mass. Notably, the coating prepared with 6 g/L CN exhibited a dense, uniform, and fine-grained microstructure, resulting in superior corrosion resistance. Additionally, the optimized coating demonstrated strong interfacial adhesion, with a shear strength of 10.05 ± 1.2 MPa.

Source: Coatings

DOI: 10.3390/coatings15091018

Authors: Xian Zhang, Hong-Hong Zhang, Kang Wu, Yan Zhang, Zhong-Nian Yang, Yu Chen

Institutions: Shandong University of Aeronautics, Foshan University

Language: English

Topic: Corrosion Behavior and Inhibition

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,137

Funders: National Natural Science Foundation of China, Natural Science Foundation of Shandong Province