Synthesis and Characterization of Nano-TiO 2 Dispersed Composite Coating by Electro-co-deposition G. Parida, D. Chaira, A. Basu* Department of Metallurgical and Materials Engineering National Institute of Technology, Rourkela Odisha, India www.nitrkl.ac.in Electro-co-deposition and Ni coating o Plane of work o Results (effect of texture and particle on properties) Results (effect of texture and particle on properties) o o Summary o Contact *: basua@nitrkl.ac.in, anindya.basu@gmail.com International Conference on Materials for advanced Technologies (ICMAT 2011 ) 26 June – 1 July 2011, Suntec, Singapore
Electro-co-deposition � Mechanism for solution deposition � Mechanism for ceramic powder (electro phoretic) Parameters deposition deposition Additives pH of the solution Electrolyte temperature Current density Electrolyte agitation Metal ion l concentration Aggregated particle Dispersed particle
Ni coating Ni coating Electro deposition Electro ‐ deposition Corrosion resistance Low cost Low temperature requirement p q Electrical conductivity y Low energy requirement Thermal conductivity Nickel Capability to handle complex Magnetostriction property geometry Physical appearance Physical appearance Simple scale ‐ up with easily Improve maintained equipment mechanical Good chemical stability properties Electro-co-deposition Electro co deposition � Particle and grain size control � pH � pH � Organic surfactant Wear resistance Ceramic � Agitation Protection against high temp particles particles Corrosion and oxidation Corrosion and oxidation resistance Hardness
Plan o Plan of Wor f f Work k k Ultrafine TiO 2 dispersed Ni coating on the mild steel substrate using Electro-co-deposition method. g p Electro deposition for nano ‐ dispersed coating Characterization Microstructure Chemical Analysis Mechanical (SEM, FESEM,AFM) (EDS) (Hardness, wear) Correlation with process parameter � Effect of surfactant and texture study
Deposition Parameters Deposition Parameters Electrolyte Nickel sulphate (NiSO 4 .6H 2 O): 350 g/l (Watt’s bath) (Watt s bath) Nickel chloride (NiCl 6H O): 45 g/l Nickel chloride (NiCl 2 .6H 2 O): 45 g/l Boric acid (H 3 BO 4 ): 37 g/l Wetting agent Sodium dodecyl sulphate: 0.2 g/l Surfactant Hexadecylpyridinium bromide: 0, 0.1, 0.3 g/l Dispersion Titania (TiO 2 ): 5, 10, 15 g/l pH pH 4 4 Temperature ( o C) 60 5 A/dm 2 Current density Plating time 30 minutes Potential Flat DC
Results TiO 2 Particle Characterization IEP Particle size XRD TEM
XRD and Texture study (of Ni) = ∑ I I / / I I × ( hkl ) 0 ( hkl ) TC 100 % ( hkl ) ( I / I ) ( hkl ) 0 ( hkl ) Coating/sample Grain size Texture coefficient (nm) (111) (200) (220) (311) Ni, no TiO 2 and 31 0.18 0.25 0.08 0.50 surfactant 5 g TiO 5 g TiO 2 , no no 30 0.17 0.10 0.63 0.10 surfactant 10 g TiO 2 , no nlarged 20 0.21 0.11 0.54 0.15 surfactant Deposition without surfactant 15 g TiO 2 , no 24 24 0 14 0.14 0.07 0 07 0 71 0.71 0.07 0 07 En surfactant 5 g TiO 2 , 0.1 g/l 30 0.29 0.33 0.09 0.29 surfactant 10 g TiO 2 , 0.1 g/l 40 0.29 0.32 0.08 0.30 su ac a surfactant 15 g TiO 2 , 0.1 g/l 33 0.15 0.70 0.03 0.12 surfactant 5 g TiO 2 , 0.3 g/l 35 0.22 0.08 0.56 0.13 surfactant 10 g TiO 2 , 0.3 g/l 10 g TiO 0 3 g/l 28 0.24 0.10 0.56 0.10 surfactant 15 g TiO 2 , 0.3 g/l 33 0.15 0.06 0.70 0.09 surfactant
EDS study 10 g/l TiO 2 without surfactant Particle deposition rate
SEM Micrograph 5 g/l TiO 2 without surfactant 15 g/l TiO 2 without surfactant 2 Parida et al., Surf. Coat. Technol., 205 (2011), 4871
AFM Study 5 g/l TiO 2 without surfactant 10 g/l TiO 2 without surfactant
Microhardness and Wear Study Microhardness Wear with varying TiO 2 % Wear with varying surfactant %
SEM Micrograph of Wear Track MAGNIFIED Pure Nickel 15 g/l TiO 2 without surfactant
Summary � Orientation of nickel in composite coating hard [110] in zero or 0.3 g/l surfactant whereas it is softer ([100] & [211]) in 0.1 g/l surfactant. � TiO 2 co ‐ deposition rate increases more in zero or 0.3 g/l surfactant compared to 0.1 g/l surfactant. � With increase in TiO 2 surface roughness increases marginally. � Due to soft orientation and less powder loading hardness increase is less in zero or 0.3 g/l surfactant compared to 0.1 g/l surfactant. Maximum hardness reported with 0.3 g/l surfactant and 15 g/l TiO 2 . � The wear test results show similar trend as microhardness due to combined effect of � The wear test results show similar trend as microhardness due to combined effect of nickel orientation and TiO 2 amount in the coating. Wear mechanism primarily adhesive in nature and the worn out particle shifts it nominally to abrasive regime.
Acknowledgment A k g Department of Science and Technology (DST), India [G [Grant No. SR/FTP/ETA/A-10/08] t N SR/FTP/ETA/A 10/08] Thank You! Thank You!
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