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Articles 121 - 150 of 249
Full-Text Articles in Metallurgy
Functionally Graded Materials By Laser Metal Deposition (Preprint), Syamala R. Pulugurtha, Joseph William Newkirk, Frank W. Liou, Hsin-Nan Chou
Functionally Graded Materials By Laser Metal Deposition (Preprint), Syamala R. Pulugurtha, Joseph William Newkirk, Frank W. Liou, Hsin-Nan Chou
Materials Science and Engineering Faculty Research & Creative Works
Fabrication of functionally graded materials (FGMs) by laser metal deposition (LMD) has the potential to offer solutions to key engineering problems over the traditional metalworking techniques. But the issues that need to be addressed while building FGMs are intermixing in the layers and cracking due to the residual stresses. This paper is to present the study of the effect of process parameters (laser power and travel speed) on the degree of dilution between the substrate (or, previous layer) and powder material for few metallurgical systems.
Effect Of Friction Stir Processing On Fatigue Behavior Of An Investment Cast Al-7si-0.6 Mg Alloy, S. Jana, Rajiv S. Mishra, J. B. Baumann, G. Grant
Effect Of Friction Stir Processing On Fatigue Behavior Of An Investment Cast Al-7si-0.6 Mg Alloy, S. Jana, Rajiv S. Mishra, J. B. Baumann, G. Grant
Materials Science and Engineering Faculty Research & Creative Works
Cast aluminum alloys in general show poor fatigue performance due to the presence of defects. Friction stir processing (FSP) can be used as a tool to enhance the mechanical properties of cast alloys by eliminating such defects. in the present study FSP led to a five times improvement in fatigue life of an investment cast Al-7Si-0.6 Mg hypoeutectic alloy. the reason for such an enhancement was linked to the closure of casting porosities, which acted as crack nucleation sites in the as cast condition. Porosities acted as notches in the as cast alloy and led to an order of magnitude …
Influence Of Fraction Of High Angle Boundaries On The Mechanical Behavior Of An Ultrafine Grained Al-Mg Alloy, R. Kapoor, N. Kumar, R. S. Mishra, C. S. Huskamp, K. K. Sankaran
Influence Of Fraction Of High Angle Boundaries On The Mechanical Behavior Of An Ultrafine Grained Al-Mg Alloy, R. Kapoor, N. Kumar, R. S. Mishra, C. S. Huskamp, K. K. Sankaran
Materials Science and Engineering Faculty Research & Creative Works
The mechanical behavior of ultrafine grained AA5052 processed through different techniques-rolled, annealed, friction stir processed (FSP) and equal channel angular pressed (ECAP)-were compared and correlated with microstructure. the microstructure was characterized using electron back scattered diffraction to obtain the boundary spacing, the fraction of high angle boundaries and to estimate the dislocation density from local misorientations. Both FSP and ECAP conditions had ultrafine boundary spacing, but the fraction of high angle boundaries was larger for the FSP condition. Tensile deformation carried out at 297K, and 10-3s-1 showed a lower work-hardening rate and recovery rate for FSP as compared to the …
Friction Stir Processing Of Commercial Grade Marine Alloys To Enable Superplastic Forming, Christopher B. Smith, Arun Mohan, Rajiv S. Mishra, Murray Mahoney, Mike Miles, Scott M. Gillis, Lee M. Cerveny, Gerald Opichka
Friction Stir Processing Of Commercial Grade Marine Alloys To Enable Superplastic Forming, Christopher B. Smith, Arun Mohan, Rajiv S. Mishra, Murray Mahoney, Mike Miles, Scott M. Gillis, Lee M. Cerveny, Gerald Opichka
Materials Science and Engineering Faculty Research & Creative Works
The use of friction stir processing (FSP) on marine grade aluminum sheet has been investigated with the objective of locally enhancing the material properties. This can potentially allow low-cost commercial grade aluminum to be used in superplastic forming applications or further enhance the formability to allow more complex geometries to be formed. FSP has been demonstrated to enable super plasticity (uniform elongations >250%) in 5083-H116 over a range of friction stir processing conditions. © (2010) Trans Tech Publications.
An Analysis Of Strength And Ductility Of Ultrafine Grained Al Alloys, R. Kapoor, P. S. De, R. S. Mishra
An Analysis Of Strength And Ductility Of Ultrafine Grained Al Alloys, R. Kapoor, P. S. De, R. S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
This paper brings together and compares data of various ultrafine grained (UFG) Al alloys processed through different routes. in general, the trend of decreasing ductility with increasing strength was observed for the UFG alloys. as compared to the coarse grained (CG) alloys, the UFG alloys show a lower ductility, a lower extent of work-hardening and a lower uniform elongation. Unlike the CG alloys, which show a large fraction of uniform to total elongation, in UFG alloys this fraction varies with processing technique. It is shown here that aging of some UFG Al alloys improves ductility. Further, it is shown that …
Effect Of Stress Ratio On The Fatigue Behavior Of A Friction Stir Processed Cast Al-Si-Mg Alloy, S. Jana, Rajiv S. Mishra, J. B. Baumann, G. Grant
Effect Of Stress Ratio On The Fatigue Behavior Of A Friction Stir Processed Cast Al-Si-Mg Alloy, S. Jana, Rajiv S. Mishra, J. B. Baumann, G. Grant
Materials Science and Engineering Faculty Research & Creative Works
The effect of friction stirs processing (FSP) on the fatigue life of a cast Al-7Si-0.6 Mg alloy at stress ratios of R = 0 and R = -1 was evaluated. Two types of specimen geometry were used for the FSPed condition, through thickness processed and partial thickness processed. at R = 0, the microstructural refinement enhanced the fatigue life by a factor of 15, whereas at R = -1 the improvement in fatigue life was 5-fold. in light of these observations, various closure mechanisms were examined. © 2009 Acta Materialia Inc.
Dislocation-Particle Interaction At Elevated Temperatures, Rajiv S. Mishra
Dislocation-Particle Interaction At Elevated Temperatures, Rajiv S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
There is a major difference in dislocation-particle interaction at low and elevated temperatures. This article will only discuss the historic development of and the current understanding of the interaction of dislocations with non-shearable particles at elevated temperatures. It will show that the understanding of repulsive-attractive transition in dislocation-particle interaction at elevated temperatures has undergone remarkable change and is at a level where a physics-Based high-temperature strengthening framework can be developed. © TMS 2009.
Thickness Effects On The Ac And Dc Electrical Behavior Of Rf-Sputtered Batio3 Nano-Capacitors With Pt And Ni Electrodes, James N. Reck, Matthew O'Keefe, Fatih Dogan
Thickness Effects On The Ac And Dc Electrical Behavior Of Rf-Sputtered Batio3 Nano-Capacitors With Pt And Ni Electrodes, James N. Reck, Matthew O'Keefe, Fatih Dogan
Materials Science and Engineering Faculty Research & Creative Works
Nanoscale BaTiO3 capacitors were deposited on Si wafers at dielectric thicknesses of approximately 25, 50, 100, and 200 nm using RF-magnetron sputtering with either 25 nm thick Ni or Pt electrodes. Multiple DC and AC tests were conducted on these devices to determine the effects of BaTiO3 thickness on the measured dielectric behaviors. All films were observed to have non-linear responses for resistance, permittivity, and loss with respect to dielectric thickness. The permittivity was found to follow a standard dead layer model behavior with measured values ranging from approximately 350 to 1700 for Ni electrodes and approximately 100 …
Preface, Judy Schneider, Rajiv S. Mishra, Thomas R. Bieler, Yuntian T. Zhu, Khaled B. Morsi, Viola L. Acoff, Eric M. Taleff, Ruslan Valiev
Preface, Judy Schneider, Rajiv S. Mishra, Thomas R. Bieler, Yuntian T. Zhu, Khaled B. Morsi, Viola L. Acoff, Eric M. Taleff, Ruslan Valiev
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Microstructural Modification Of As-Cast Al-Si-Mg Alloy By Friction Stir Processing, Z. Y. Ma, S. R. Sharma, Rajiv S. Mishra
Microstructural Modification Of As-Cast Al-Si-Mg Alloy By Friction Stir Processing, Z. Y. Ma, S. R. Sharma, Rajiv S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
Friction stir processing (FSP) has been applied to cast aluminum alloy A356 plates to enhance the mechanical properties through microstructural refinement and homogenization. the effect of tool geometry and FSP parameters on resultant microstructure and mechanical properties was investigated. the FSP broke up and dispersed the coarse acicular Si particles creating a uniform distribution of Si particles in the aluminum matrix with significant microstructural refinement. Further, FSP healed the casting porosity. These microstructural changes led to a significant improvement in both strength and ductility. Higher tool rotation rate was the most effective parameter to refine coarse Si particles, heal the …
Effect Of Friction Stir Processing On The Microstructure Of Cast A356 Aluminum, Z. Y. Ma, S. R. Sharma, Rajiv S. Mishra
Effect Of Friction Stir Processing On The Microstructure Of Cast A356 Aluminum, Z. Y. Ma, S. R. Sharma, Rajiv S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
Friction stir processing (FSP) was applied to cast A356 Al to modify the as-cast microstructure. FSP homogenizes and refines the cast microstructure, completely eliminates porosity, and creates a microstructure with fine Si particles (0.25-0.42 μm) distributed in a fine grain aluminum matrix (3-4 μm). Further, FSP parameters significantly influence microstructural development in the processed zone of cast A356 Al. Generally, higher tool rotation rate creates a more homogeneous microstructure. at lower tool rotation rates, a macroscopically visible banded structure characterized by a low density of coarse particles, was detected in the nugget zone. However, FSP parameters did not significantly influence …
Effect Of Welding Parameters On Properties Of 5052 Al Friction Stir Spot Welds, T. A. Freeney, S. R. Sharma, Rajiv S. Mishra
Effect Of Welding Parameters On Properties Of 5052 Al Friction Stir Spot Welds, T. A. Freeney, S. R. Sharma, Rajiv S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
Effect of process parameters on friction stir spot welding (FSSW) of 5052 Al alloy has been evaluated. a plunge type FSSW machine was used for this study. Sheet thicknesses of 1 and 1.6mm were used. the tool rotation rate was varied between 1000 and 3000 rpm. the tool plunge rate and dwell time was varied to give weld cycle of 1-4 seconds. Shear tests were performed in 2 sheet and 3 sheet configurations to determine the influence of processing parameters on the mechanical properties of lap joint FSSWs. Higher joint strengths were observed at lower tool rotation rates. Copyright © …
Journal Of Materials Engineering And Performance: Editorial, C. Suryanarayana, Leon L. Shaw, Rajiv S. Mishra
Journal Of Materials Engineering And Performance: Editorial, C. Suryanarayana, Leon L. Shaw, Rajiv S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Approaches Toward Integrating Functionality Into Structural Materials, Rajiv S. Mishra
Approaches Toward Integrating Functionality Into Structural Materials, Rajiv S. Mishra
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Superplasticity In Cast A356 Induced Via Friction Stir Processing, Z. Y. Ma, Rajiv S. Mishra, M. W. Mahoney
Superplasticity In Cast A356 Induced Via Friction Stir Processing, Z. Y. Ma, Rajiv S. Mishra, M. W. Mahoney
Materials Science and Engineering Faculty Research & Creative Works
Super plasticity was investigated in friction stir processed A356 alloy at temperatures of 470-570 °C and initial strain rates of 3x10 -4-1x10-1 s-1. Maximum superplastic elongation of 650% was obtained at 530 °C and an initial strain rate of 1x10-3 s-1 where a maximum strain rate sensitivity of 0.45 was observed. © 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Segmented Roll For Casting Metal Strip, James R. Sauer, Ronald J. O'Malley, Robert S. Williams
Segmented Roll For Casting Metal Strip, James R. Sauer, Ronald J. O'Malley, Robert S. Williams
Materials Science and Engineering Faculty Research & Creative Works
Casting molten metal using a segmented roll for casting continuous metal strip. A strip caster (10) for producing a continuous strip (18) includes a tundish for containing a melt and a pair of horizontally disposed water cooled composite casting rolls (84). The casting rolls are juxtaposed relative to one another for forming a pouring basin (16) for receiving molten metal. The composite rolls are formed from a plurality of annular segments (45). Each segment preferably includes at least a pair of coolant openings (34) and means for aligning the coolant openings, such as a pair of alignment openings (26). The …
Evaluation Of Lead Anode Reactions In Acid Sulfate Electrolytes: Ii. Manganese Reactions, Pu Yu, Thomas J. O'Keefe
Evaluation Of Lead Anode Reactions In Acid Sulfate Electrolytes: Ii. Manganese Reactions, Pu Yu, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
Lead alloys containing calcium-tin, silver, or similar combinations are the primary insoluble anodes used for copper and zinc electrowinning. One potential concern with these anodes is the detrimental effect on cathode purity from incorporation of lead corrosion products. Other factors which are important to process economics are the reaction potential and overpotential required for oxygen evolution. In addition to the inherent overpotential, impurities in the electrolyte can have a significant polarization impact, such as the films that may form when manganese is present. In order to gain a better understanding of the fundamental behavior of various concentrations of manganese ions …
Misinformation [1], Hollis P. Leighly
Misinformation [1], Hollis P. Leighly
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Evaluating And Monitoring Nucleation And Growth In Copper Foil, Ye Kun Lee, Thomas J. O'Keefe
Evaluating And Monitoring Nucleation And Growth In Copper Foil, Ye Kun Lee, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
The electrodeposition of copper foil for use in electronic materials applications is a complex and demanding process. The specific aspects of producing and controlling the structure-property-performance requirements of the foil are important because of the stringent demands placed on their use in printed circuit boards and similar products. In this paper, a brief review of the electrodeposition process for raw copper foil is presented. Since electrolyte additives play such a significant role in the copper-deposition process, the effects of two essential additives, chloride ion and an organic (e.g., glue or gelatine), on the foil are described. Also, the influence of …
Electrochemical Characterization Of The Effects Of Impurities And Organic Additives In Lead Electrowinning From Fluoborate Electrolyte, Puqiang Zhang, Thomas J. O'Keefe, Pu Yu
Electrochemical Characterization Of The Effects Of Impurities And Organic Additives In Lead Electrowinning From Fluoborate Electrolyte, Puqiang Zhang, Thomas J. O'Keefe, Pu Yu
Materials Science and Engineering Faculty Research & Creative Works
The effects of glue and calcium lignin sulfonate additives, and chloride and antimony impurities on the lead electrowinning process, using a fluoborate electrolyte, were studied. Short-term deposition tests, voltammetry, electrochemical impedance spectroscopy (EIS) and SEM techniques were used for the evaluation. The interactions among additives and impurities were also evaluated. The presence of antimony or chloride ion in the range of 50 to 200 mg/L was shown to cause a more dendritic and powdery lead deposit. Additions of glue and calcium lignin sulfonate at selected concentrations helped to level the deposit and counteracted the detrimental effects of chloride and antimony. …
Properties Of Sputtered Bilayer Wnx/W Diffusion Barriers Between Si And Cu, K. D. Leedy, Matthew O'Keefe, E. J. Dahlgren, J. T. Grant
Properties Of Sputtered Bilayer Wnx/W Diffusion Barriers Between Si And Cu, K. D. Leedy, Matthew O'Keefe, E. J. Dahlgren, J. T. Grant
Materials Science and Engineering Faculty Research & Creative Works
Copper interconnect metallizations in next generation integrated circuits will require thin diffusion barrier layers (< 20 nm) between the Cu and low-k dielectric which may also function as seed layers for subsequent material depositions. One possible structure entails a multicomponent diffusion barrier with a lower resistivity component, such as W on WNx. In this study, sputtered WNx/W bilayer thin films were investigated as diffusion barriers between Si and Cu. The total thickness of the WNx/W bilayer was fixed at 20 nm while the WNx thickness was varied from 0 to 20 nm. After deposition of the barrier films, a 100 nm thick Cu film was sputtered over the top of the ct-W and amorphous WNx bilayer. The as-deposited WNx/W film stress was found to be strongly dependent on the relative amount of WNx and W present and the addition of a Cu overlayer was found to mitigate the stress levels. The WNx/W barriers remained stable after 650°C anneals and exhibited phase transformations to W 2N. Microstructural characterization using transmission electron microscopy and x-ray diffraction and chemical analysis by x-ray photoelectron spectroscopy of the films were used to identify the as deposited and transformed phases. © 2001 Materials Research Society.
Rms Titanic: A Metallurgical Problem, Hollis P. Leighly, B. L. Bramfitt, S. J. Lawrence
Rms Titanic: A Metallurgical Problem, Hollis P. Leighly, B. L. Bramfitt, S. J. Lawrence
Materials Science and Engineering Faculty Research & Creative Works
No abstract provided.
Characterization And Soldering Of Organic Modified Aluminum Thin Films And Bond Pads, Rui Fang, Eric Dahlgren, Matthew O'Keefe, Thomas J. O'Keefe, Wu Sheng Shih, Daniel R. Gamota, Jie Zhang
Characterization And Soldering Of Organic Modified Aluminum Thin Films And Bond Pads, Rui Fang, Eric Dahlgren, Matthew O'Keefe, Thomas J. O'Keefe, Wu Sheng Shih, Daniel R. Gamota, Jie Zhang
Materials Science and Engineering Faculty Research & Creative Works
An immersion plating process using organic solutions was used to deposit a seed layer of copper and to activate the surface of thin film aluminum surfaces and bond pads. The seeded surfaces were subsequently electroless copper plated and tested for compatibility with soldering assembly. It was demonstrated that the copper particles deposited from the organic solution onto sputter deposited aluminum thin films were able to act as nucleation sites for the subsequent buildup of adherent, continuous copper films from conventional electroless plating baths. In addition, the metal deposition from organic solution process was found to be very selective on patterned …
Spontaneous, Non-Aqueous Electrochemical Deposition Of Copper And Palladium On Al And Al(Cu) Thin Films, R. Fang, H. Gu, Matthew O'Keefe, Thomas J. O'Keefe, W. S. Shih, K. D. Leedy, R. Cortez
Spontaneous, Non-Aqueous Electrochemical Deposition Of Copper And Palladium On Al And Al(Cu) Thin Films, R. Fang, H. Gu, Matthew O'Keefe, Thomas J. O'Keefe, W. S. Shih, K. D. Leedy, R. Cortez
Materials Science and Engineering Faculty Research & Creative Works
Copper and palladium seed layers have been successfully deposited from organic solutions onto patterned and unpatterned pure aluminum and Al (0.5%Cu) thin films using an immersion displacement process. The reaction occurs at ambient temperature and pressure by a spontaneous electrochemical mechanism. Copper and palladium deposition using the organic solution was studied as a function of reaction time and Cu or Pd concentration in the solution. It was found that both time and the initial ionic metal concentration significantly influence deposit morphology, particle size and shape, and adherence. Nucleation of Cu or Pd sub-micron particles on both Al and Al (Cu) …
Evaluation Of Nickel Deposition By Electrochemical Impedance Spectroscopy, M. Holm, Thomas J. O'Keefe
Evaluation Of Nickel Deposition By Electrochemical Impedance Spectroscopy, M. Holm, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
Electrochemical impedance spectroscopy was used to characterize the deposition of nickel from unbuffered acid sulfate electrolytes, from which a wide range of deposit morphologies and current efficiencies are possible. The operating parameters were in the range of 40 to 60 g L-1 Ni2+, 40 to 60 °C, and the pH from 2.0 to 3.5. The resulting impedance spectra for nickel deposition at 20 mA cm-2 consisted of one or two characteristic loops whose frequency and capacitance were dependent upon the electrowinning conditions and indicative of the resultant deposit morphology. A single high frequency capacitive loop, on the order of 1 …
The Anomalous Behavior Of Al³⁺ In Nickel Electrowinning From Sulfate Electrolytes, Michael Holm, Thomas J. O'Keefe
The Anomalous Behavior Of Al³⁺ In Nickel Electrowinning From Sulfate Electrolytes, Michael Holm, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
The effect of varying concentrations of Al3+ on the morphology and current efficiency of electrodeposited nickel from an acid-sulfate electrolyte was studied. Concentrations of Al3+ of 20 to 100 ppm significantly degraded the nickel-cathode morphology and current efficiency. However, it was found that higher concentrations of Al3+, in the range of 1 to 5 g/L, depending on the electrolyte parameters and operating conditions, improved the deposit morphology compared to deposition from a pure electrolyte. However, the current efficiency remained low. Physical characterization of the nickel revealed that a smoother, more uniform surface resulted from deposition in …
Organic Solution Deposition Of Copper Seed Layers Onto Barrier Metals, H. Gu, R. Fang, Thomas J. O'Keefe, Matthew O'Keefe, W. S. Shih, J. A.M. Snook, K. D. Leedy, R. Cortez
Organic Solution Deposition Of Copper Seed Layers Onto Barrier Metals, H. Gu, R. Fang, Thomas J. O'Keefe, Matthew O'Keefe, W. S. Shih, J. A.M. Snook, K. D. Leedy, R. Cortez
Materials Science and Engineering Faculty Research & Creative Works
Spontaneous deposition of copper seed layers from metal bearing organic based solutions onto sputter deposited titanium, titanium nitride, and tantalum diffusion barrier thin films has been demonstrated. Based on electrochemically driven cementation exchange reactions, the process was used to produce adherent, selectively deposited copper metal particulate films on blanket and patterned barrier metal thin films on silicon substrates. The organic solution deposited copper films were capable of acting as seed layers for subsequent electrolytic and electroless copper deposition processes using standard plating baths. Electroless and electrolytic copper films from 0.1μm to 1.0μm thick were produced on a variety of samples …
Evaluation Of Lead Anode Reactions In Acid Sulfate Electrolytes. I. Lead Alloys With Cobalt Additives, Pu Yu, Thomas J. O'Keefe
Evaluation Of Lead Anode Reactions In Acid Sulfate Electrolytes. I. Lead Alloys With Cobalt Additives, Pu Yu, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
Lead alloys, such as lead-calcium-tin and lead-silver, are the primary insoluble anodes used in the electrowinning of metals. While some difficulties are encountered in their use, there is no obvious replacement that is economically and technically competitive. Two of the specific problems with lead include decreased cathode purity due to incorporation from corrosion products and the relatively high overpotential which increases cell voltage. To gain an improved understanding of the fundamental behavior of lead anodes, the polarization behavior of six different alloys in sulfuric acid was evaluated. Some tests were also made with Co(II) in the acid sulfate electrolyte. Notable …
Modeling The Dielectric Response And Relaxation Spectra Of Relaxor Ferroelectrics, Huh Tswen Lin, David C. Van Aken, Wayne Huebner
Modeling The Dielectric Response And Relaxation Spectra Of Relaxor Ferroelectrics, Huh Tswen Lin, David C. Van Aken, Wayne Huebner
Materials Science and Engineering Faculty Research & Creative Works
A multi-Debye relaxation model that is based upon the Boltzmann superposition principle has been used to determine the frequency-dispersion behavior of Pb (Mg1/3-Nb2/3)O3 (PMN) and Pb0.88La0.08 (Zr0.65Ti0.35) O3 (PLZT 8/65/35) relaxor ferroelectrics. For PMN, relaxation times on the order of seconds contribute to the dispersive character of the dielectric properties. A defect-relaxation mechanism that involves Mg cation hopping in a structure that is composed of interpenetrating 〈111〉 chains of ordered Pb (Mg1/2Nb1/2) O3 is proposed for PMN. Motion of the Mg cations …
Copper Nucleation On Titanium For Thin Film Applications, A. J.B. Dutra, Thomas J. O'Keefe
Copper Nucleation On Titanium For Thin Film Applications, A. J.B. Dutra, Thomas J. O'Keefe
Materials Science and Engineering Faculty Research & Creative Works
Copper nucleation and growth on titanium substrates from concentrated acidic copper sulfate solutions was studied at 45 and 65 °C and high cathodic potentials. Electrochemical experiments allied to SEM examination were performed to characterize the mechanism of nucleation and its evolution with time. Particular emphasis was given to the influence of potential and agitation on the initial stages of nucleation and growth. Results indicated that most of copper nucleation on titanium from a 83 g dm-3 Cu2+ solution, at 65 °C, is achieved in a matter of milliseconds. As expected, the initial stages of the copper nucleation and growth is …