Influence of Boron Concentration on the Corrosion Resistance of High Boron White Cast Iron to Liquid Zinc Bath

Autor: Jian Dong Xing, Jianjun Zhang, Sheng Qiang Ma, Sheng Chao Ma, Guofeng Liu, Da Wei Yi
Rok vydání: 2010
Předmět:
Zdroj: Key Engineering Materials. 457:219-224
ISSN: 1662-9795
DOI: 10.4028/www.scientific.net/kem.457.219
Popis: The influence of boron concentration on corrosion resistance of high boron white cast iron dipped into a pure liquid zinc bath at 460°C was investigated. The results reveal that high boron white cast iron containing 3.5 wt.%B exhibits excellent corrosion resistance due to the dense continuous netlike or parallel Fe2B phase which hinders the Fe/Zn interface reaction. The corrosion rate decreases significantly when the boron concentration increases, but the corrosion rate declines slightly when the boron concentration exceeds 3.5wt.%. EDS results indicate the coarse and compact δ phase generated near the matrix and a large amount of massive and blocky  phase occurred close to the liquid zinc. The corrosion process includes Fe/Zn interface reaction and the spalling and fracture of Fe2B. The failure of Fe2B is mainly caused by the microcrack of phase transformation.
Databáze: OpenAIRE