Affordable electrolytic ferrotitanium alloys with marine engineering potentials

作者：Li Guoming; Jin Xianbo^*; Wang Dihua; Chen George Z

来源：Journal of Alloys and Compounds, 2009, 482(1-2): 320-327.

DOI：10.1016/j.jallcom.2009.04.007

• Titanium alloys
• Powder processing
• Electrochemistry
• Corrosion
• Molten salts

Fe2O3 and TiO2 powders were compounded in different proportions at elevated temperatures. Porous thin pellets were made from the compounded oxides and then electro-reduced to the respective ferrotitanium alloys and/or intermetallic compounds in solid state in molten CaCl2. Typical electrolysis conditions were 800-1000 degrees C, 2.8-3.2 V and 4-15 h. X-ray diffraction, scanning electron and optical microscopy, and potentiodynamic polarisation were used to characterise the oxide precursors and/or the products. The results showed that the obtained Fe-Ti alloys achieved the designated elemental compositions. When the Fe content in the oxide precursor was less than 50 wt.%, the products were mainly mixed Ti and Fe-Ti alloys. At higher Fe contents, the products changed to a mixture of Fe2Ti and Fe. Between 8 and 15 wt.% Fe, the products sintered most severely. The Fe-rich Fe-Ti alloys had better corrosion resistance than a common ship hull steel (E36) in simulated sea water, i.e. the aqueous solution of 3 wt.% NaCl. The Ti-rich Fe-Ti alloys (8 wt.% Fe) had good corrosion resistance to the 1.0 mol/L HCl solution. The addition of Nb in the alloys improved the corrosion resistance, but the addition of Al caused the opposite effect.

• 出版日期2009-8-12
• 单位中国人民解放军海军工程大学; 武汉大学