morpho-structural characterization and electrophoretic deposition of xonotlite obtained by a hydrothermal method

In this research, xonotlite was synthesized by a hydrothermal method in the si-ca-na-h2o system. detailed structural characterization by using the xrd technique revealed that the obtained material contains a small quantity of wollastonite (up to 3 %) as an impurity. calcination of the obtained sample at 900 ˚c has resulted in a complete transformation of xonotlite to wollastonite which was detected as only a crystal phase. crystallite size and lattice strain of all crystal phases were calculated using scherrer and williamson-hall method. sem observation of xonotlite morphology revealed tiny needle-like crystals joined together forming dendritic or globular aggregates. optimal conditions for electrophoretic deposition of xonotlite on 304-type stainless steel have been achieved by appropriate selection of electric field strengths, dispersing medium, and dispersants. stable suspension of the material was obtained using isopropanol containing 1 % water as dispersing medium and ca-nitrate as a charging additive. native layers of xonotlite have a very smooth morphology, while after calcination, the appearance of small cracks in the coating can be observed but the adhesion strength of the coatings to the substrate is improved.