Doctor of Philosophy, Case Western Reserve University, 2019, Chemical Engineering

High-performance microprocessors and memory devices require miniaturized copper (Cu) interconnects that carry electrical signals to circuit elements such as transistors. Conventionally, these nanoscale Cu interconnects are fabricated using electrodeposition; however, with the continued scaling of the interconnects below 10 nm, electrodeposition does not allow the requisite atomic-scale control over the interconnect fabrication process. As a result, future interconnect fabrication will require novel materials fabrication techniques. Vapor-phase atomic layer deposition (ALD) is a promising alternative to replace the conventional electrodeposition approach; however, a major drawback of the vapor-phase Cu ALD process is that it uses metalorganic precursors which are highly unstable, undergo decomposition and thus introduce contaminants in the metal deposit. To address such critical issues, we pursue here the development of an electrochemical atomic layer deposition (e-ALD) process which utilizes benign liquid-phase precursors in combination with electrode potential manipulation for the deposition of atomic-scale metal films. In the present work, a novel electrochemical atomic layer deposition process for copper (Cu) and cobalt (Co) is developed. The process is mediated by zinc underpotential deposition (Znupd) which serves as a sacrificial adlayer. Zn underpotential deposition is studied using cyclic voltammetry and quartz crystal microbalance. Chronoamperometry studies on a rotating disk electrode provide insights into the diffusion-reaction properties of the Znupd process. A general strategy for e-ALD is developed which involves deposition of a sacrificial monolayer of Zn via underpotential deposition followed by its spontaneous redox replacement (SLRR) by the desired noble metal (Cu or Co). UPD+SLRR cycles are repeated to build multi-layered metal deposits with controlled thickness in the sub-nm range and minimal surface roughness amplification. Layer-by-laye (open full item for complete abstract)

Master of Science, The Ohio State University, 2012, Aero/Astro Engineering

An accelerated deposition test facility was used to study the relationship between film cooling, surface temperature, and particle temperature at impact on deposit formation. Tests were run at gas turbine representative inlet Mach numbers (0.1) and temperatures (1090°C). Deposits were created from lignite coal fly ash with median diameters of 1.3 and 8.8µm. Two CFM56-5B nozzle guide vane doublets, comprising three full passages and two half passages of flow, were utilized as the test articles. Tests were run with different levels of film cooling back flow margin and coolant temperature. Particle temperature upon impact with the vane surface was shown to be the leading factor in deposition. Since the particle must traverse the boundary layer of the cooled vane before impact, deposition is directly affected by the film and metal surface temperature as well. Film coolant jet strength showed only minor effect on deposit patterns on the leading edge. However, larger Stokes number (resulting in higher particle impact temperature) corresponded with increased deposit coverage area on the shower head region. Additionally, infrared measurements showed a strong correlation between regions of greater deposits and elevated surface temperature on the pressure surface. Thickness distribution measurements also highlighted the effect of film cooling by showing reduced deposition immediately downstream of cooling holes. A set of secondary tests were also conducted to briefly study the effect of Stokes number on leading edge deposition with no cooling, in order to support conclusions from the primary tests. It was found that larger Stokes number led to an increase in rate of deposition due to a greater number of particles being able to follow their inertial trajectories and impact the vane. Implications for engine operation in particulate-laden environments are discussed.

Master of Science, The Ohio State University, 1952, Graduate School

Doctor of Philosophy, University of Akron, 2023, Polymer Science

Plasma polymerization is a facile method of depositing robust films on a wide variety of substrates. While the nanoscale structure of films plasma polymerized in vacuum has been studied some, little is known of the nanoscale structure of the films deposited in the more complex atmospheric plasma polymerized (APP) films. To explore how deposition conditions affect APP film structures, APP films were deposited using hexamethyldisiloxane (HMDSO) precursor at varying power and in varying levels of relative humidity (RH). X-ray and neutron reflectivity measurements reveal that these APP-HMDSO films have a three-layer structure. A transition region of low mass density and carbon content forms next to the substrate as the deposition starts and etching by the plasma initially dominates deposition; a center region which still experiences some etching displays a uniform scattering length density (SLD) with respect to depth; a surface layer next to the air of mass density less than or equal to that of the center region forms whose SLD depends on how “filled in” the layer was when plasma generation was halted. Mass density was found to be sensitive to high humidity, which reduces the flux of monomer fragments to the substrate and allows them to pack more densely. Complementary analysis of depth-resolved X-ray photoelectron spectroscopy and water contact angle measurements show that composition and hydrophilicity are power-dependent. Films deposited at lower power lose more of their carbon to etching, making their composition more silica-like and making them more hydrophilic. Films deposited at higher power retain more of the carbon from the HMDSO monomer thanks to higher deposition rates; a film layer is buried by additional layers before all the residual carbon can be etched away. Neutron reflectivity measurements of the same APP-HMDSO films while exposing them to deuterated solvent vapor showed that vapor easily penetrated them without causing their thickness to increase, (open full item for complete abstract)

Master of Science in Engineering, Youngstown State University, 2023, Department of Mechanical, Industrial and Manufacturing Engineering

The field of metal additive manufacturing has experienced significant growth in recent years, and Laser Hot Wire Directed Energy Deposition (LHW-DED) has emerged as a popular technology due to its ease of use and ability to produce high-quality metal parts. In this study, we used a nonlinear transient thermo-mechanical coupled finite element model (FEM) in ANSYS APDL to conduct a detailed thermal and structural analysis of the laser hot wire DED metal additive manufacturing process. This analysis aimed to characterize the distortion caused by thermal effects and investigate the transient thermal process. In this study H13 iron chromium alloy material was deposited on an A36 low carbon steel substrate using a bidirectional laser toolpath. To record the temperature profile during printing, we employed a FLIR Infrared (IR) camera, while thermocouples mounted to the base plate measured heat transfer for validation purposes. Post-processing analysis was conducted using the CREAFORM laser 3D scan and Geomagic-X software to measure deformation from the nominal printed geometry. Overall, this study provides a significant contribution to our understanding of laser hot wire DED metal additive manufacturing, which will undoubtedly lead to further advancements in the field. This research has the potential to improve the productivity and quality of the additive manufacture of metals.

Doctor of Philosophy, The Ohio State University, 2021, Electrical and Computer Engineering

This dissertation focuses on the development of chemical vapor deposition (CVD) of β-Ga2O3, an ultra-wide bandgap (UWBG) semiconductor representing one of the most promising semiconducting materials for next generation power electronics. Here, two types of CVD thin film deposition techniques were investigated, including the metalorganic chemical vapor deposition (MOCVD) and the low pressure chemical vapor deposition (LPCVD) methods. The main goal of this work aims to establish the fundamental understanding of this emerging UWBG semiconductor material through comprehensive mapping of the growth parameters combined with extensive material characterization. β-Ga2O3, with an ultra-wide bandgap of 4.5-4.9 eV and capability of n-doping, promises its applications for high power electronics. β-Ga2O3 is predicted to have a high breakdown field (~ 8 MV/cm) with room temperature mobility of ~200 cm2/Vs. The Baliga figure of merit (BFOM) of β-Ga2O3 for power electronics is predicted to be 2 to 3 times higher than that of GaN and SiC. One key advantage for β-Ga2O3 is from its availability of high quality and scalable native substrates synthesized via melt growth methods, which is critical to large-scale production with low cost. Thus, this UWBG material has great potential for future generation high power electronics as well as deep ultraviolet optoelectronics. The MOCVD growth window was explored for β-Ga2O3 thin films grown on native Ga2O3 substrates. Group IV Si was identified as an effective n-type dopant with a wide doping range from 1016-1020 cm-3. Under optimized growth conditions, β-Ga2O3 thin films grown on semi-insulating Fe-doped (010) Ga2O3 substrates demonstrated superior room temperature carrier mobilities of 184 and 194 cm2/V·s with and without intentional Si doping at charge concentration of 2.7×1016 cm-3 and 8.5×1015 cm-3, respectively. Temperature-dependent Hall measurements revealed a peak mobility of ~ 9500 cm2/V·s with extremely low compensation concen (open full item for complete abstract)

Master of Science, The Ohio State University, 2020, Aero/Astro Engineering

This thesis covers the intensive research effort to elucidate the role of elevated temperature in deposition. Several experimental campaigns were conducted in this pursuit. The testing explored high temperature deposition with 0-10 micron Arizona Road Dust (ARD) with the intent of creating a yield strength model that included temperature effects and could be incorporated into the existing OSU deposition model. Experimental work was first conducted in the impulse kiln facility where small amounts of the test dust were placed on ceramic targets and rapidly exposed to temperatures between 1200K and 1500K. Trends in the packing factor confirmed the existence of two threshold values (1350K and 1425K) that could be linked to strength characteristics of the dust when exposed to high temperatures. Using the information obtained from the kiln experiments, HTDF testing was conducted between 1325K and 1525K. Exit temperatures were set at 25K intervals in this region with a constant jet velocity of 150 m/s. The capture efficiency data showed this trend with temperature and indicated a softening temperature and melting temperature of 1362K and 1512K respectively. With these critical values in hand, the Ohio State University Molten Model was created to modify yield strength with particle velocity and temperature. The model was tested using CFD and showed a good capability for capturing particle temperature effects in deposition from an impinging particle-laden jet. A subsequent test campaign was conducted to explore the effect of varying surface temperature on deposition. Hastelloy coupons with Thermal Barrier Coatings (TBCs) were subjected to a constant jet at 1600K jet and 200 m/s while being cooled via a backside impingement jet. Surface temperatures between 1455K and 1125K were impacted with 0-10 micron ARD while an IR camera monitored the surface. Coupons with higher coolant flowrates (lower surface temperature) saw significantly lower deposition rates than the higher surf (open full item for complete abstract)

Doctor of Philosophy (Ph.D.), University of Dayton, 2013, Materials Engineering

Synthesizing nanostructures represents a critical technology in the field of materials science. The ability to actively control the structure and composition of matter have allowed some of the greatest scientific achievements in the last decade. This document explores the synthesis and characterization of various carbon nanostructures (e.g. DNA and doped fullerene materials). Furthermore, this document addresses how these materials can be processed into low dimensional solids while maintaining compositional integrity. Processing methods include Matrix Assisted Pulsed Laser Deposition (MAPLE), thermal evaporation, and Chemical Vapor Deposition (CVD). The synthesized bulk structures were analyzed using physical and structural measurements. Project conclusions provided insight into the unique structure-property relationships in these materials.

Master of Science, The Ohio State University, 2013, Aero/Astro Engineering

A high temperature combustion rig was used to impact bituminous and lignite coal fly ash particles on an impingement plate at conditions similar to those found in the hot section of a gas turbine engine. Individual particles were tracked using particle shadow velocimetry as they either rebounded from or deposited on the plate surface. The effects of particle size, particle impact velocity, impact angle, particle temperature, and plate temperature were explored. Particle diameter ranged from 30-800µm, impact velocity ranged from 5-160 m/s, impact angle ranged from close to 0° to 90°, and temperatures ranged from ambient conditions to 2100°F. Increasing diameter, impact velocity, and plate temperature were all shown to decrease the total coefficient of restitution. The angular coefficient of restitution was shown to decrease with increased impact angle for bituminous ash. The total coefficient of restitution versus both impact angle and particle temperature yielded unexpected trends. For bituminous ash, a peak in coefficient of restitution occurred for all temperature cases at an impingement angle of 40°. Both higher and lower impact angles resulted in a decrease in coefficient of restitution. A peak in coefficient of restitution occurs between 1250-1500°F for both the bituminous and lignite ash, decreasing at both higher and lower temperatures. Possible explanations for these unexpected results are discussed.

Master of Science (MS), Wright State University, 2011, Chemistry

Solid oxide fuel cell (SOFC) technology has attracted great attention due to advantages such as low emissions and high efficiency. In this work, solid oxide fuel cells were fabricated by incorporating functional layers deposited by a novel aerosol jet® printing method. The buffer and cathode layers were printed from gadolinium doped ceria (Ce0.9Gd0.1)O1.95 (CGO) and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) inks, respectively. The CGO layer was deposited on the sintered electrolyte and then LSCF was subsequently deposited onto the CGO layer. The polarization curves showed a 19% improvement in current density using LSCF as the cathode instead of LSM. Cathode grain size was shown to change by 85% over the sintering temperatures examined. Lastly, the effect that ethyl cellulose additive had on the resulting cathode was determined. It was discovered that the porosity of the microstructure was not correlated to the additive's molecular weight. The actual causes of the cathode porosity may be the order of polymer branching or the ethoxy content of the ethyl cellulose.

Master of Science, The Ohio State University, 2010, Aeronautical and Astronautical Engineering

A new turbine research facility at The Ohio State University Aeronautical and Astronautical Research Lab has been constructed. The purpose of this facility is to re-create deposits on the surface of actual aero-engine Nozzle Guide Vane (NGV) hardware in an environment similar to what the hardware was designed for. This new facility is called the Turbine Reacting Flow Rig (TuRFR). The TuRFR provides air at temperatures up to 1200 °C and at inlet Mach numbers comparable to those found in an actual turbine (~0.1). Several validation studies have been undertaken which prove the capabilities of the TuRFR. These studies show that the temperature entering the NGV cascade is uniform, and they demonstrate the capability to provide film cooling air to the NGV cascade at flow rates and density ratios comparable to the NGV design. Deposition patterns have also been created on the surface of actual NGV hardware. Deposition was created at different flow temperatures, and it was found that deposition levels decrease with decreasing gas temperature. Also, film cooling levels were varied from 0% film cooling to 4% film cooling. It was found that with increased rates of film cooling deposition decreased. With the TuRFR capabilities demonstrated, research on the effects of deposition on the aerodynamic performance of the NGV hardware was conducted. Integrated non-dimensional total pressure loss values were calculated in an exit Rec range of 0.2x106 to 1.7x106 for a deposit roughened NGV cascade and a smooth cascade. The data suggests that deposition causes increased losses across the NGV cascade and possibly earlier transition. The data also suggests a possible region of separated flow in the NGV cascade which disappears at higher exit Reynolds numbers. These results are similar to those found in the literature.

Doctor of Philosophy, The Ohio State University, 2004, Materials Science and Engineering

The Laser Engineered Net Shaping (LENS™) system, a type of directed laser manufacturing, has been used to create compositionally graded materials. Using elemental blends, it is possible to quickly vary composition, thus allowing fundamental aspects of phase transformations and microstructural development for particular alloy systems to be explored. In this work, it is shown that the use of elemental blends has been refined, such that bulk homogeneous specimens can be produced. When tested, the mechanical properties are equivalent to conventionally prepared specimens. Additionally, when elemental blends are used in LENS™ process, it is possible to deposit compositionally graded materials. In addition to the increase in design flexibility that such compositionally graded, net shape, unitized structures offer, they also afford the capability to rapidly explore composition-microstructure-property relationships in a variety of alloy systems. This research effort focuses on the titanium alloy system. Several composition gradients based on different classes of alloys (designated a, a+b, and b alloys) have been produced with the LENS™. Once deposited, such composition gradients have been exploited in two ways. Firstly, binary gradients (based on the Ti-xV and Ti-xMo systems) have been heat treated, allowing the relationships between thermal histories and microstructural features (i.e. phase composition and volume fraction) to be explored. Neural networks have been used to aid in the interpretation of strengthening mechanisms in these binary titanium alloy systems. Secondly, digitized steps in composition have been achieved in the Ti-xAl-yV system. Thus, alloy compositions in the neighborhood of Ti-6Al-4V, the most widely used titanium alloy, have been explored. The results of this have allowed for the investigation of composition-microstructure-property relationships in Ti-6-4 based systems.

Master of Science (MS), Ohio University, 1990, Mechanical Engineering (Engineering)

OVD Project: The purpose of this study is to present a numerical solution of the thermophoretic deposition process which occurs in the Outside Vapor Deposition technique used in the fabrication of optical fiber preforms. In the OVD technique a mixture of gasses is combined and emitted from a nozzle. A typical mixture may include methane, oxygen, nitrogen, silicon tetrachloride, and germanium chloride. Upon exiting the nozzle the methane and oxygen ignite to form a flame jet. The large amount of heat released upon combustion induces a chemical reaction in which silicon dioxide particles doped with germanium dioxide are produced. The jet of particle laden gases flows past a cylindrical bait rod. Since the bait rod is much cooler than the flame, high temperature gradients are developed in the boundary layer over the cylinder. This temperature gradient produces thermophoretic motion of the particles in the flame jet, and the particles deposit on the bait rod. Successive layers of particles are deposited in this way to produce the preform. The thermophoretic deposition of particles involves many factors such as fluid motion and heat and mass transfer so the analysis of the process is quite difficult. Analysis has been carried out by Alam and Mehrotra (1987), and Homsy et al. (1981). In these analyses a simple uniform flow was assumed, and the target rod was assumed to have a uniform temperature. The uniform flow assumption is obviously highly simplistic. Experiments have been carried out at Ohio University (Graham et al., 1989), which indicate that the uniform temperature assumption is also not valid. In the present analysis, the flow is taken to be that of a free jet aimed at a surface with a variable temperature profile. The free jet dimensions correspond to the flame jets used in OVD systems, and the temperature profile on the target surface is based on experimental results. The heat and mass transfer problem is then solved in two phases. First, the flow equations and (open full item for complete abstract)

Master of Science (MS), Ohio University, 1986, Mechanical Engineering (Engineering)

The purpose of the study was to investigate the deposition of fine particles from a flow, onto surfaces, and to relate the deposition process to the flow conditions. Both, internal & external boundary layer type flows have been studied. These can be related to the conditions encountered in the Modified Chemical Vapor Deposition (MCVD) and Outside Vapor Deposition (OVD) processes used in optical waveguide fabrication. For internal flows, the equations that govern the energy and particle transport are relatively simple and have been studied by previous researchers who suggested that thermophoresis is the dominant particle transport mechanism. This has been confirmed by our study too. The new aspect of our research is that we have included the particle size calculations in our model. External flows are more difficult to analyze because of the added burden of evaluating the flow field. Another difficulty is the growth of the boundary layer. To avoid this, a coordinate transformation has been used that makes the domain of computation rectangular and the boundary layer growth in these coordinates negligible. The governing equations are solved, once again, using a finite difference technique. The results obtained agree well with those of Homsy et. al., who used a Blasius series technique in terms of universal functions. Results indicate that the deposition rate is greater for larger temperature differences between the flow and deposition surface. The dependance on Reynolds number of the free stream has also been analysed.

Master of Science (MS), Ohio University, 2000, Chemical Engineering (Engineering)

Residual stress in gallium nitride films grown on silicon substrates by metalorganic chemical vapor deposition

Doctor of Philosophy (Ph.D.), University of Dayton, 2011, Mechanical Engineering

Jet fuel is used in high-performance military flight vehicles for cooling purposes before combustion. It is desirable to investigate the influence of the flow and heating conditions on fuel heat transfer and thermal stability to develop viable mitigation strategies. Computational fluid dynamics (CFD) simulations and experiments can provide the understanding of the fuel physical phenomena which involves the fluid dynamics, heat transfer and chemical reactions. Three distinct topics are studied: The first topic considers the effect of flow geometry on fuel oxidation and deposition. Experiments and CFD modeling were performed for fuels flowing through heated tubes which have either a sudden expansion or contraction. It was found that the peak deposition occurs near the maximum oxidation rate and excess deposition is formed near the step. This study provides information for the fuel system designer which can help minimize surface deposition due to fuel thermal oxidation. In the second area of study, the fuel passed heated rotational test articles to investigate the effect of rotation on fuel heat transfer. The coupled effects of centrifugal forces and turbulent flow result in fuel temperatures that increase with rotational speed. This indicates that the convective heat transfer is enhanced as rotational speed increases. This work can assist the understanding of using jet fuel to cool the turbine engine. In the third segment of research, the fuel was exposed to “rocket-like” conditions. This investigation is to explore the effect of high heat flux and high flow velocity on fuel heat transfer and oxidation/deposition. Simulations show a temperature difference over several hundred degrees in the radial direction within the very thin thermal boundary layer under rapid heating. The fuel contacting the interior wall is locally heated to a supercritical state. As a result, the heat transfer is deteriorated in the supercritical boundary layer. Both simulated and measured dep (open full item for complete abstract)

Doctor of Philosophy, Case Western Reserve University, 2006, Chemical Engineering

Tribological thin films are of interest to designers and end-users of friction management and load transmission components such as steel rolling element bearings. This study sought to reveal new information about the properties and formation of such films, spanning the scope of their technical evolution from natural oxide films, to antiwear films from lubricant additives, and finally engineered nanocomposite metal carbide/amorphous hydrocarbon (MC/a-C:H) films. Transmission electron microscopy (TEM) was performed on the near-surface material (depth < 500 nm) of tapered roller bearing inner rings (cones) that were tested at two levels of boundary-lubricated conditions in mineral oil with and without sulfur- and phosphorus-containing gear oil additives. Site-specific thinning of cross-section cone surface sections for TEM analyses was conducted using the focused ion beam milling technique. Two types of oxide surface films were characterized for the cones tested in mineral oil only, each one corresponding to a different lubrication severity. Continuous and adherent antiwear films were found on the cone surfaces tested with lubricant additives, and their composition depended on the lubrication conditions. A sharp interface separated the antiwear film and base steel. Various TEM analytical techniques were used to study the segregation of elements throughout the film volume. The properties of nanocomposite tantalum carbide/amorphous hydrocarbon (TaC/a-C:H) thin films depend sensitively on reactive magnetron sputtering deposition process conditions. TaC/a-C:H film growth was studied as a function of three deposition parameters in designed experiments: acetylene flow rate, applied d.c. bias voltage, and substrate carousel rotation rate. Empirical models were developed for the following film characteristics to identify process-property trend relationships: Ta/C atomic ratio, hydrogen content, film thickness, TaC crystallite size, Raman spectrum, compressive stress, hardness, (open full item for complete abstract)

Master of Science, University of Akron, 2006, Applied Mathematics

Plasma enhanced physical vapor deposition (PEPVD) is one method to coat nanofibers and nanostructures with thin film materials. Experimental efforts in coating electrospun polymer nanofibers suggest a complicated relationship between coating morphology and operating conditions. This motivates a theoretical model for coating growth. The model presented here assumes a coating growth that is uniform along the axial dimension of the nanofiber but non-uniform in the radial direction. The concentration of vaporized aluminum surrounding the coating growth is non-uniform due to the geometry of the coating growth, therefore modeling the morphology of the growth requires that the surrounding concentration field be determined. The concentration field would then be supplied to an evolution equation. The mode of mass transport is diffusion, therefore the mathematical model consists of Laplace's equation over a polar domain. The domain is an annulus with an irregular inner boundary. A finite difference method is employed to solve the system. The irregular inner boundary geometry, as well as a complicated inner boundary condition, requires that interpolation schemes and ghost points be used at points on and near the boundary. The resulting matrix system is solved with a block SOR iterative method.

Doctor of Philosophy, University of Toledo, 2013, College of Arts and Sciences

Real time spectroscopic ellipsometry (RTSE), and ex-situ mapping spectroscopic ellipsometry (SE) are powerful characterization techniques capable of performance optimization and scale-up evaluation of thin film solar cells used in various photovoltaics technologies. These non-invasive optical probes employ multichannel spectral detection for high speed and provide high precision parameters that describe (i) thin film structure, such as layer thicknesses, and (ii) thin film optical properties, such as oscillator variables in analytical expressions for the complex dielectric function. These parameters are critical for evaluating the electronic performance of materials in thin film solar cells and also can be used as inputs for simulating their multilayer optical performance. In this Thesis, the component layers of thin film hydrogenated silicon (Si:H) solar cells in the n-i-p or substrate configuration on rigid and flexible substrate materials have been studied by RTSE and ex-situ mapping SE. Depositions were performed by magnetron sputtering for the metal and transparent conducting oxide contacts and by plasma enhanced chemical vapor deposition (PECVD) for the semiconductor doped contacts and intrinsic absorber layers. The motivations are first to optimize the thin film Si:H solar cell in n-i-p substrate configuration for single-junction small-area dot cells and ultimately to scale-up the optimized process to larger areas with minimum loss in device performance. Deposition phase diagrams for both i- and p-layers on 2" x 2" rigid borosilicate glass substrate were developed as functions of the hydrogen-to-silane flow ratio in PECVD. These phase diagrams were correlated with the performance parameters of the corresponding solar cells, fabricated in the Cr/Ag/ZnO/n/i/p/ITO structure. In both cases, optimization was achieved when the layers were deposited in the protocrystalline phase. Identical solar cell structures were fabricated on 6" x 6" borosilicate (open full item for complete abstract)

Master of Science in Engineering, Youngstown State University, 2024, Department of Mechanical, Industrial and Manufacturing Engineering

This is a study on optimizing the Laser Hot-wire Directed Energy Deposition (LHW-DED) process Invar 36 steel deposition onto an A36 mild steel substrate. This study aims to investigate Numerical Analysis as well as thermocouple measurements, on the transient thermal model to discuss potential solidification mechanisms. Unlike most-existing studies which focus is on single or few-layer geometries, this research presents a multi-layered model capable of predicting thermal analysis during deposition. A transient thermal model was developed to evaluate the effects of conduction, convection and radiation on the printing beads. The numerical model results were compared with the temperature data measured using thermocouples. The integration of experimental and numerical approaches enhance the accuracy of the findings, providing valuable insight into the thermal behavior of the DED process. This understanding is crucial for optimizing parameters and improving the quality of printed structures. The study highlights the significance of accurately modeling thermal interactions to advance the precision and efficiency of DED additive manufacturing. The detailed study of the LHW-DED additive manufacturing process focusing on the experimental setup, materials used, and the potential impact of the research on advancing the understanding and application of this innovative manufacturing technology. The numerical simulation with experimental data is to ensure the accuracy of the thermo-mechanical model. This will involve in measuring profiles, residual stresses, and material properties during the actual LHW-DED process.