The study of the effectiveness of corrosion protection of zinc-rich coating on the base of water sodium silicate

Issue 25(4) 2020
Pages 32-39

Le Hong Quan, Russian-Vietnamese Tropical Center, Hanoi, Vietnam
Nguyen Van Chi, Russian-Vietnamese Tropical Center, Hanoi, Vietnam
Mai Van Minh, Russian-Vietnamese Tropical Center, Hanoi, Vietnam
Nong Quoc Quang, Russian-Vietnamese Tropical Center, Hanoi, Vietnam
Dong Van Kien, Russian-Vietnamese Tropical Center, Hanoi, Vietnam


Keywords: corrosion, electrochemical properties, water sodium silicate, z inc-rich paint

doi: 10.31615/j.corros.prot.2020.98.4-4

 

The study is examines the assessment of the corrosion-protective properties of zinc-rich coating based on water sodium silicate (ZRC) using the Electrochemical Impedance Spectra (EIS) with AutoLAB PGSTAT204N. The system consists of three electrodes: Ag/AgCl reference electrode in 3 M solution of KCl, auxiliary electrode – Pt (8x8 mm) and working electrodes for determination potential (Ecorr) and impedance measurement, salt spray test method and natural teszzt method at Dam Bay Marine Research Station, Nha Trang, Khanh Hoa, Viet Nam. ZSC can provide good cathodic protection when zinc content is 70% by weight or more. ZSC with a mixing ratio of High Modulus Liquid Sodium Glass / Zinc Powde : 25/75 by weight (working title – TTL-VN) has good corrosion protection after 16 cycles salt spray test and after 18 months natural test in seawater. The paint film has basic parameters as adhesion – 4,41 MPa, flexural strength – 2 mm, pendulum
hardness – 0,62 conventional units and initial coating potentia l – 0,96 V Ag/AgCl.