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The influence of scanning speed on laser metal deposition of Ti/TiC powders

- Sobiyi, K. K., Akinlabi, Esther Titilayo, Akinlabi, Stephen A.

  • Authors: Sobiyi, K. K. , Akinlabi, Esther Titilayo , Akinlabi, Stephen A.
  • Date: 2017
  • Subjects: Titanium , Lasers , Metal deposition
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/241302 , uj:24840 , Citation: Sobiyi, K.K. 2017. The influence of scanning speed on laser metal deposition of Ti/TiC powders.
  • Description: Abstract: This paper describes the experimental work performed on laser metal deposition (LMD) of titanium carbide powders on pure titanium substrate. The understanding the effect of LMD processing parameters is vital in controlling the properties of the final product fabricated from the LMD process. The objective of the study is to characterize the influence of laser scanning speed of metal deposition of titanium and titanium carbide powders on pure titanium substrate. Microstructural characterization results showed that the substrate is characterized by two-phase morphology; alpha and beta phase. Deposit zone microstructures showed that the grains are of continuous columnar in nature. Heat affected zone region grain areas appear to decrease with increasing in scanning speed for different samples at different scanning speeds. The height of samples at different scanning was observed to decrease with increase in scanning speed. Microhardness results showed that the hardness of the deposits is greater than the hardness of the substrate. Wear resistance performance results showed that the coefficient of friction of substrate is greater than the coefficient of friction of the deposit samples. Wear volume loss of material of the substrate is higher than the deposits. The deposit contains titanium carbide and, as such, this powder has improved the wear resistance performance of the substrate.
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Prediction of municipal solid waste generation : an investigation of the effect of clustering techniques and parameters on ANFIS model performance

- Adeleke, Oluwatobi, Akinlabi, Stephen A., Jen, Tien-Chien, Dunmade, Israel

  • Authors: Adeleke, Oluwatobi , Akinlabi, Stephen A. , Jen, Tien-Chien , Dunmade, Israel
  • Date: 2020
  • Subjects: Waste generation , Adaptive Neuro-Fuzzy Inference System , Clustering-techniques
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/461246 , uj:41074 , Citation: Adeleke, O. et al. 2020. Prediction of municipal solid waste generation : an investigation of the effect of clustering techniques and parameters on ANFIS model performance.
  • Description: Abstract: The present waste management system and facilities in most developing countries are insufficient to combat the challenge of increasing rate of solid waste generation. To achieve success in sustainable solid waste management, planning plays a crucial role. Accurate prediction of waste quantities generated will immensely help to overcome the challenge of deficient-planning of sustainable waste management. This challenge has necessitated the need for modelling approach. In modelling the complexity within a system, a paradigm-shift from classical-model to artificial intelligent model has been necessitated. Previous researches which used Adaptive Neuro-Fuzzy Inference System (ANFIS) for waste generation forecast did not investigate the effect of clustering-techniques and parameters on the performance of the model despite its significance in achieving accurate prediction. This study therefore investigates the impact of the parameters of three clustering-technique namely: Fuzzy c-means (FCM), Grid-Partitioning (GP) and Subtractive-Clustering (SC) on the performance of the ANFIS model in predicting waste generation using South Africa as a case study. Socio-economic and demographic provincial-data for the period 2008-2016 were used as input-variables and provincial waste quantities as output-variable. ANFIS model clustered with GP using triangular input membership-function (tri-MF) and a linear type output membership-function (ANFIS-GP1) is the optimal model with Mean Absolute Percentage Error (MAPE), Mean Absolute Deviation (MAD), Root Mean Square Error (RMSE) and Correlation Co-efficient (R2) values of 12.6727, 0.6940, 1.2372 and 0.9392 respectively. Based on the result in this study, ANFIS-GP with a triangular membership-function is recommended for modelling waste generation. The tool presented in this study can be utilized for the national repository of waste generation data by the South Africa Waste Information Centre (SAWIC) in South Africa and it is also applicable to waste-planners in developing countries for reliable and accurate prediction of annual waste generation.
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Powder flow rate influence on laser metal deposited tic on ti-6al-4v

- Akinlabi, Esther Titilayo, Akinlabi, Stephen A.

  • Authors: Akinlabi, Esther Titilayo , Akinlabi, Stephen A.
  • Date: 2016
  • Subjects: Powder flow rate , Tic , Ti-6al-4v
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/93277 , uj:20328 , Citation: Akinlabi, E.T. & Akinlabi, S.A. 2016. Powder flow rate influence on laser metal deposited tic on ti-6al-4v.
  • Description: Abstract: Laser metal deposition (LMD) presents a suitable substitute for conventional machining of titanium products. It is an additive manufacturing technology used to build prototypes, models, tools, dies and end products. The process is used to manufacture components from materials, which are difficult to machine through conventional methods. Titanium and its alloys are one of the difficult materials to machine since they cause galling on the cutting tool. This paper reports on the material characterization of Laser Metal deposited TiC on Titanium alloy grade 5 and the effect of varying the powder flow rate on the evolving properties of the material. The clads were characterized through microstructural analysis, hardness and degree of porosity. The physical appearances of the samples appeared sound without defect. However, the surfaces of the samples were rough. Furthermore, the average microhardness decreased as the powder flow rate was increased. The microstructural evaluation revealed that the grain size in the deposit zone becomes shorter as the powder flow rate was increased. The microstructure in the heat-affected zone had smaller grain sizes relative to the grain sizes in the deposit zone. In addition, the porosity characterization revealed that the number of pores increases when the powder flow rate increases.
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Non-destructive testing of dissimilar friction stir welds

- Akinlabi, Esther Titilayo, Levy, Adrian C. S., Akinlabi, Stephen A.

  • Authors: Akinlabi, Esther Titilayo , Levy, Adrian C. S. , Akinlabi, Stephen A.
  • Date: 2012
  • Subjects: Friction stir welding , Non-destructive testing , Aluminum alloys , Copper
  • Type: Article
  • Identifier: uj:5333 , ISSN 2078-0966 , http://hdl.handle.net/10210/8876
  • Description: friction stir welds between 5754 aluminium alloy and C11000 copper. The Friction stir welds of 5754 aluminium alloy and C11000 copper were produced at different tool rotational speeds and feed rates. The tool rotational speed was varied between 600 and 1200 rpm while the feed rate was varied between 50 and 300 mm/min. The visual inspection and the x-ray radiographic testing techniques were employed to conduct the tests; these tests were conducted on the welds to ascertain the joint integrity before characterization to have an idea of the quality of the welds. No visual defects were observed on all the welds considered but the x-ray radiography technique revealed the presence of wormhole defects and discontinuities in some of the welds. It was found that the welds produced at 950 rpm with varied feed rates were the best quality welds produced and this was substantiated with the microstructural evaluation of the joint interface. It was found that these welds have good mixing and metallurgical bonding at the interfaces.
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Neuro-fuzzy resource forecast in site suitability assessment for wind and solar energy: a mini review

- Adedeji, Paul A., Akinlabi, Stephen A., Madushele, Nkosinathi, Olatunji, Obafemi O.

  • Authors: Adedeji, Paul A. , Akinlabi, Stephen A. , Madushele, Nkosinathi , Olatunji, Obafemi O.
  • Date: 2020
  • Subjects: ANFIS-based modeling , GIS , MCDM
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/436562 , uj:37873 , Adedeji, P.A. 2020:Neuro-fuzzy resource forecast in site suitability assessment for wind and solar energy: a mini review. DOI: https://doi.org/10.1016/j.jclepro.2020.122104
  • Description: Abstract: , Site suitability problems in renewable energy studies have taken a new turn since the advent of geographical information system (GIS). GIS has been used for site suitability analysis for renewable energy due to its prowess in processing and analyzing attributes with geospatial components. Multi-criteria decision making (MCDM) tools are further used for criteria ranking in the order of influence on the study. Upon location of most appropriate sites, the need for intelligent resource forecast to aid in strategic and operational planning becomes necessary if viability of the investment will be enhanced and resource variability will be better understood. One of such intelligent models is the adaptive neuro-fuzzy inference system (ANFIS) and its variants. This study presents a mini-review of GIS-based MCDM facility location problems in wind and solar resource site suitability analysis and resource forecast using ANFIS-based models. We further present a framework for the integration of the two concepts in wind and solar energy studies. Various MCDM techniques for decision making with their strengths and weaknesses were presented. Country specific studies which apply GIS-based method in site suitability were presented with criteria considered. Similarly, country-specific studies in ANFIS-based resource forecasts for wind and solar energy were also presented. From our findings, there has been no technically valid range of values for spatial criteria and the analytical hierarchical process (AHP) has been commonly used for criteria ranking leaving other techniques less explored. Also, hybrid ANFIS models are more effective compared to standalone ANFIS models in resource forecast, and ANFIS optimized with population-based models has been mostly used. Finally, we present a roadmap for integrating GIS-MCDM site suitability studies with ANFIS-based modeling for improved strategic and operational planning.
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Mitigating backdrop in operational efficiency : a case study

- Akinlabi, Stephen A., Mbohwa, Charles

  • Authors: Akinlabi, Stephen A. , Mbohwa, Charles
  • Date: 2016
  • Subjects: Planning , Scheduling , Rail freight
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/215025 , uj:21355 , Citation: Akinlabi, S.A & Mbohwa, C. 2016. Mitigating backdrop in operational efficiency : a case study.
  • Description: Abstract: The main focus of this investigation was to identify the backdrop in the operational efficiency of a rail company in South Africa - Transnet Freight Railways (TFR) and profer solutions. Qualitative approach was adopted through the administering of questionnaires to respondents in Transnet company. Even though Transnet makes effort to resolve the problems, the outcome of the results still show that the system of schedling is not consistent to a specifc standard and the turnaround time is still between poor and fair. In addition, wagon and locomotives failures is identified as one of the factors contributing to the backdrop in the operational efficiency of the TFR system. It is therefore recommended that adopting a good maintenenace system to the wagon and locomotive may help to reduce if not eliminate failures of the wagons and the locomotive. This will consequently help to improve the backdrop in the operational efficiency of the TFR system.
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Microstructural development during mechanical forming of steel sheets

- Akinlabi, Stephen A., Akinlabi, Esther Titilayo

  • Authors: Akinlabi, Stephen A. , Akinlabi, Esther Titilayo
  • Date: 2013
  • Subjects: Microhardness , Metal forming , Steel - Deformation
  • Type: Article
  • Identifier: uj:4852 , ISBN 978-988-19251-0-7 , http://hdl.handle.net/10210/12519
  • Description: Metal forming is used synonymously with deformation, a process during which an object gets changed due to the applied force. These changes can either be reversible or irreversible depending on the type of material; size and geometry of the object and the magnitude of the applied force to the object. This paper reports the microstructural development after mechanical forming of steel sheet material by varying the applied loads. The microstructural evaluations showed that the applied loads employed caused an increase in the magnitude of the grain sizes in each loaded specimen. Furthermore, the increase in the grain size of the microstructure was observed to be directly proportional to the loads applied. In addition, the microhardness values of the cross sections investigated were found to increase with the applied loads. Hence, the grain size growth and the hardness were linearly dependent on the applied loads, and this implies that there is a correlation between the applied loads and the resulting microstructure of the material and the hardness of the material.
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Microstructural characterizations of dissimilar friction stir welds

- Akinlabi, Esther Titilayo, Reddy, Randall D., Akinlabi, Stephen A.

  • Authors: Akinlabi, Esther Titilayo , Reddy, Randall D. , Akinlabi, Stephen A.
  • Date: 2012
  • Subjects: Friction stir welding , Scanning Electron Microscopy , Aluminum alloys , Copper
  • Type: Article
  • Identifier: uj:5332 , ISSN 2070-3740 , http://hdl.handle.net/10210/8871
  • Description: This paper reports the microstructural characteristics of dissimilar friction stir welds between 5754 aluminium alloy and C11000 copper. Dissimilar Friction Stir Welds of 5754 aluminium and C11000 copper were produced by varying the rotational speeds between 600 and 1200 rpm and the feed rate between 50 and 300 mm/min. The welds were characterized through Scanning Electron Microscopy (SEM). The SEM analysis revealed the levels of metallurgical bonding achieved at the joint interfaces of the welds produced and it can be established that better metallurgical bonding and good mixing of both materials joined were achieved in welds produced at lower feed rates of 50 mm/min and 150 mm/min while defect population was found to be common in the welds produced at high feed rate of 300 mm/min.
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Methods of improving turnaround time of iron ore wagon utilisation

- Mabhena, Thembisile, Akinlabi, Stephen A., Mbohwa, Charles

Material characterization studies on the laser beam formed AISI 1008 mild steel

- Kumpaty, Subha, Brossard, Bradley, Kamara, Sheku, Akinlabi, Stephen A., Akinlabi, Esther Titilayo, Raju, Govinda, Panda, Nirmal, Balasubramanian, K.

  • Authors: Kumpaty, Subha , Brossard, Bradley , Kamara, Sheku , Akinlabi, Stephen A. , Akinlabi, Esther Titilayo , Raju, Govinda , Panda, Nirmal , Balasubramanian, K.
  • Date: 2014
  • Subjects: Mechanical forming , Laser beam forming , Metal deformation
  • Type: Article
  • Identifier: uj:4743 , ISSN 978-93-81505-62-5 , http://hdl.handle.net/10210/11729
  • Description: Laser Beam Forming is a new non-contact method without the use of a die, to achieve deformation in metals, which traditionally involved the application of mechanical forces to change the shape and form of the material permanently. Laser forming causes deformation by introducing thermal stresses from an external heat source as opposed to the simple application of forces in mechanical forming. In this study, samples were formed mechanically by using a dynamic press brake machine, whereby, a punch and die apply the force. A 4.4 kW Nd:YAG laser system was used to form a second set of samples made from cold rolled AISI 1008 mild steel using laser forming. In this collaborative work involving researchers from the USA, South Africa and India, the mechanical and metallurgical properties of the unformed, mechanically formed and laser formed samples were experimentally investigated. The objective is to compare these properties amongst the different samples in order to analyze the impact of the varying methodologies especially the laser energy effects on the samples. The conclusions from these tests have provided valuable information on the applicability of laser forming to attain the appropriate surface modifications yielding the desired mechanical and metallurgical properties of the metal.
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Material characterization studies on the laser beam formed AISI 1008 mild steel

- Kumpaty, Subha, Brossard, Bradley, Kamara, Sheku, Akinlabi, Stephen A., Akinlabi, Esther Titilayo, Raju, Govinda, Panda, Nirmal, Balasubramanian, K.

  • Authors: Kumpaty, Subha , Brossard, Bradley , Kamara, Sheku , Akinlabi, Stephen A. , Akinlabi, Esther Titilayo , Raju, Govinda , Panda, Nirmal , Balasubramanian, K.
  • Date: 2013
  • Subjects: Metal-work , Metals , Thermal stresses , Steel - Heat treatment
  • Type: Article
  • Identifier: uj:5097 , http://hdl.handle.net/10210/13713
  • Description: Laser Beam Forming is a new non-contact method without the use of a die, to achieve deformation in metals, which traditionally involved the application of mechanical forces to change the shape and form of the material permanently. Laser forming causes deformation by introducing thermal stresses from an external heat source as opposed to the simple application of forces in mechanical forming. In this study, samples were formed mechanically by using a dynamic press brake machine, whereby, a punch and die apply the force. A 4.4 kW Nd:YAG laser system was used to form a second set of samples made from cold rolled AISI 1008 mild steel using laser forming. In this collaborative work involving researchers from the USA, South Africa and India, the mechanical and metallurgical properties of the unformed, mechanically formed and laser formed samples were experimentally investigated. The objective is to compare these properties amongst the different samples in order to analyze the impact of the varying methodologies especially the laser energy effects on the samples. The conclusions from these tests have provided valuable information on the applicability of laser forming to attain the appropriate surface modifications yielding the desired mechanical and metallurgical properties of the metal.
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Laser forming of titanium and its alloys – an overview

- Akinlabi, Esther Titilayo, Shukla, Mukul, Akinlabi, Stephen A.

Inspection of market products : a case study

- Ntlhane, Makibane Daniel, Akinlabi, Stephen A., Mbohwa, Charles

Hybrid neurofuzzy wind power forecast and wind turbine location for embedded generation

- Adedeji, Paul A., Akinlabi, Stephen A., Madushele, Nkosinathi, Olatunji, Obafemi O.

  • Authors: Adedeji, Paul A. , Akinlabi, Stephen A. , Madushele, Nkosinathi , Olatunji, Obafemi O.
  • Date: 2020
  • Subjects: ANFIS , Embedded generation genetic algorithm , Genetic algorithm
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/436546 , uj:37871
  • Description: Abstract: , Wind energy uptake in South Africa is significantly increasing both at the micro‐ and macro‐level and the possibility of embedded generation cannot be undermined considering the state of electricity supply in the country. This study identifies a wind hotspot site in the Eastern Cape province, performs an in silico deployment of three utility‐scale wind turbines of 60 m hub height each from different manufacturers, develops machine learning models to forecast very short‐term power production of the three wind turbine generators (WTG) and investigates the feasibility of embedded generation for a potential livestock industry in the area. Windographer software was used to characterize and simulate the net output power from these turbines using the wind speed of the potential site. Two hybrid models of adaptive neurofuzzy inference system (ANFIS) comprising genetic algorithm and particle swarm optimization (PSO) each for a turbine were developed to forecast very short‐term power output. The feasibility of embedded generation for typical medium‐scale agricultural industry was investigated using a weighted Weber facility location model. The analytical hierarchical process (AHP) was used for weight determination. From our findings, the WTG‐1 was selected based on its error performance metrics (root mean square error of 0.180, mean absolute SD of 0.091 and coefficient of determination of 0.914 and CT = 702.3 seconds) in the optimal model (PSO‐ANFIS). Criteria were ranked based on their order of significance to the agricultural industry as proximity to water supply, labour availability, power supply and road network. Also, as a proof of concept, the optimal location of the industrial facility relative to other criteria was X = 19.24 m, Y = 47.11 m. This study reveals the significance of resource forecasting and feasibility of embedded generation, thus improving the quality of preliminary resource assessment and facility location among site developers.
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Friction stir welding process : a green technology

- Akinlabi, Esther Titilayo, Akinlabi, Stephen A.

  • Authors: Akinlabi, Esther Titilayo , Akinlabi, Stephen A.
  • Date: 2012
  • Subjects: Friction stir welding , Green technology
  • Type: Article
  • Identifier: uj:5335 , ISSN 2010-3778 , http://hdl.handle.net/10210/8878
  • Description: Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in the United Kingdom in 1991 for butt and lap welding of metals and plastics. This paper highlights the benefits of friction stir welding process as an energy efficient and a green technology process in the field of welding. Compared to the other conventional welding processes, its benefits, typical applications and its use in joining similar and dissimilar materials are also presented.
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Friction stir welding of dissimilar materials – statistical analysis of the weld data

- Akinlabi, Esther Titilayo, Akinlabi, Stephen A.

  • Authors: Akinlabi, Esther Titilayo , Akinlabi, Stephen A.
  • Date: 2012
  • Subjects: Friction stir welding
  • Type: Article
  • Identifier: uj:5336 , ISSN 2078-0966 , http://hdl.handle.net/10210/8879
  • Description: This paper reports the results of statistical analysis conducted on the weld data obtained from friction stir welding of aluminium and copper. The welds were produced by varying the process parameters; the rotational speed was varied between 600 to 1200 rpm and the welding speed varied between 50 and 300 mm/min. The Statistica (version 9.0) statistical analysis software package was used to generate the scatter and surface plots relative to the experimental results obtained from the tensile testing and the FSW data. Regression analysis was also done on the weld data. It was found that the downward vertical force has a significant effect on the Ultimate Tensile Strength of the weld and a strong relationship exist between the heat input into the welds and the measured electrical resistivities of the welds.
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Friction stir welding of aluminium and copper : fracture surface characterizations

- Akinlabi, Esther Titilayo, Akinlabi, Stephen A.

  • Authors: Akinlabi, Esther Titilayo , Akinlabi, Stephen A.
  • Date: 2014
  • Subjects: Aluminium , Copper , Fracture surfaces , Friction stir welding
  • Type: Article
  • Identifier: uj:4745 , ISSN 2078-0966 , http://hdl.handle.net/10210/11731
  • Description: Butt welds of aluminium alloy and copper alloy were produced by Friction Stir Welding by varying the feed rate and keeping all other parameters constant. The final weld matrix was composed of welds produced by a constant rotational speed of 600 rpm and the feed rate varied between 50 and 300mm/min. The microstructure and fracture surfaces of the joint interfaces were investigated. The results revealed that the joint interface was characterised with mixed layers of both materials joined. The strongest weld was produced at the highest feed rate employed at 300 mm/min. The fracture surfaces were characterised with thin layers of intermetallic compounds and can be considered fit for practical applications.
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Fracture location characterizations of dissimilar friction stir welds.

- Akinlabi, Esther Titilayo, Akinlabi, Stephen A.

  • Authors: Akinlabi, Esther Titilayo , Akinlabi, Stephen A.
  • Date: 2011
  • Subjects: Fracture location , Friction stir welding , Intermetallics , Metallography
  • Type: Article
  • Identifier: uj:5322 , http://hdl.handle.net/10210/8230
  • Description: This paper reports the tensile fracture location characterizations of dissimilar friction stir welds between 5754 aluminium alloy and C11000 copper. The welds were produced using three shoulder diameter tools; namely, 15, 18 and 25 mm by varying the process parameters. The rotational speeds considered were 600, 950 and 1200 rpm while the feed rates employed were 50, 150 and 300 mm/min to represent the low, medium and high settings respectively. The tensile fracture locations were evaluated using the optical microscope to identify the fracture locations and were characterized. It was observed that 70% of the tensile samples failed in the Thermo Mechanically Affected Zone (TMAZ) of copper at the weld joints. Further evaluation of the fracture surfaces of the pulled tensile samples revealed that welds with low Ultimate Tensile Strength either have defects or intermetallics present at their joint interfaces.
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Experimental investigation of laser beam forming of titanium and statistical analysis of the effects of parameters on curvature

- Akinlabi, Stephen A., Akinlabi, Esther Titilayo

  • Authors: Akinlabi, Stephen A. , Akinlabi, Esther Titilayo
  • Date: 2013
  • Subjects: Laser beam forming , Titanium alloys
  • Type: Article
  • Identifier: uj:4746 , ISSN 2078-0966 , http://hdl.handle.net/10210/11732
  • Description: Laser beam forming, a non-contact manufacturing process has become a viable manufacturing process for shaping metallic components. The capability of laser beam forming and bending demands more experimental studies to identify an optimized parameter setting and the likely parameters influencing the formed curvature. This paper investigates experimental laser beam forming of Ti6Al4V titanium alloy using a 4.4 kW Nd: YAG laser and studied the effects of the process parameters on the formed curvature. It was established that an increase in both the laser beam power and the number of scan tracks reduces the radius of curvature in the formed sheets having a more dome shape. The scan speed on the other hand, achieved the same good curvature at a slower or reduced scan speed to allow enough laser – material interaction. Furthermore, both the ANOVA and the regression analysis confirmed the repeatability of the experimental data. A simple regression model was developed based on the known active parameters to determine approximate curvatures instead of running a series of experiments.
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Evaluation of structural integrity of laser formed steel sheets for possible load bearing applications

- Akinlabi, Stephen A., Shukla, M.

  • Authors: Akinlabi, Stephen A. , Shukla, M.
  • Date: 2016
  • Subjects: Structural integrity , Laser forming , Microstructural evolution
  • Language: English
  • Type: Article
  • Identifier: http://hdl.handle.net/10210/215436 , uj:21417 , Citation: Akinlabi, S.A & Shukla, M. 2016. Evaluation of structural integrity of laser formed steel sheets for possible load bearing applications.
  • Description: Abstract: Steel is a well-known material for various manufacturing applications because of its unique properties such as great formability and durability, good tensile and yield strength and good thermal conductivity. This paper reports on the evaluation of the structural integrity of laser formed steel sheets for possible load carrying applications. The tensile tests conducted revealed 46% elongation while the yield strength of the laser formed components were enhanced with about 18%. Furthermore, elongated grain structures were observed in the micrographs of the three components formed at the maximum parameter setting. It was revealed that this elongation varied indirectly to the applied line energy. The measured grain sizes further showed that the components formed at the optimized maximum process parameter window were characterized by smaller grain structures with about 60% of the grain sizes of the parent material. A progressive increase in the micro Vickers hardness of about 40% was also observed in the three laser formed components in comparison to the parent material. The analysis of the residual stresses conducted in this study revealed that the changes in the residual stresses are a function of the process condition to which the samples were subjected...
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