Effect of Titanium Oxide on Phase Transformation for Low Alloy High Strength Steel Welds

Abstract:

Aimed at improving mechanical properties of high strength low alloy steel welds, oxides with high melting point and high stability were added into steel liquid. By thermodynamics calculation and thermal simulating technology, phase transformation characteristics of low alloy steel weld with TiO₂ addition were investigated. The results showed that TiO₂ added in welds led to the decrease of phase transformation temperature and the wideness of γ→α transformation temperature range. The starting and finishing transformation temperature of ferrite respectively dropped about 311K and 486K on the cooling condition of 373K/s. Moreover, the complex inclusions of TiOx-MnO-SiO₂-MnS with spherical shape and 0.67μm mean size formed in weld metal. In addition, only acicular ferrite existed in the titanium oxide added welds. So it was concluded that titanium oxide can effectively be used to control phase transformation and then achieve fine and favorable microstructure.

• Periodical: Key Engineering Materials (Volumes 531-532)
• Pages: 92-96
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.531-532.92
• Online since: December 2012
• Authors: Cui Xin Chen, Hui Fen Peng, Pu Zhao, Yuan Yuan Li, Liang Yan
• Keywords: Acicular Ferrite, Complex Inclusion, Low Alloy Steel, Phase Transformation, Titanium Oxide

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