日本金属学会誌

J. Japan Inst. Met. Mater, Vol. 80, No. 2 (2016),
pp. 121-127

Effect of Pretreatment by Ammonium Sulfate on Galvannealing Time of Si-Bearing Galvanized Steel

Yoichi Tobiyama1, Masahiko Tada1, Sakae Fujita1, Shigenari Hayashi2 and Masao Takeyama2

1Steel Research Laboratory, JFE Steel Corporation, Fukuyama 721-8501
2Department of Metallurgy and Ceramics Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, Tokyo 152-8552

Abstract:

The effect of oxidation accelerated by ammonium sulfate prior to annealing on galvannealing time of Si-bearing galvanized steel has been investigated to develop a new process for manufacturing Si-bearing galvannealed steel.
Oxidation accelerated by ammonium sulfate prior to annealing was effective to shorten the galvannealing time of the steel. The steel treated with ammonium sulfate showed the same galvannealing time as mild steel under the conventional oxidation condition.
This is probably due to not only the suppression of the formation of external oxides, which suppressed the Fe/Zn reaction during galvannealing but also the penetration of zinc into the grain boundaries and the reduced iron layer/the steel interface during galvanizing.

[doi:10.2320/jinstmet.J2015041]


(Received 2015/6/19)

Keywords:

silicon, manganese, steel, oxidation, galvanizing, galvannealing, iron oxide, ammonium sulfate, surface segregation, external oxide


PDF(Free)PDF (Free)     Table of ContentsTable of Contents

Please do not copy without permission.