Advanced manufacture of compositionally composite graded materials : an overview
- Authors: Mahamood, R.M. , Akinlabi, Esther Titilayo , Abdulrahman, K.O. , Owolabi, M.G.
- Date: 2018
- Subjects: Additive manufacturing , Functionally graded materials , Selective laser melting
- Language: English
- Type: Book Chapter
- Identifier: http://hdl.handle.net/10210/291077 , uj:31601 , Citation: Mahamood, R.M., Akinlabi, E.T. & Abdulrahman, K.O. 2018. Advanced manufacture of compositionally composite graded materials : an overview.
- Description: Abstract: Compositionally graded composite materials are advanced materials that consists of inhomogeneous composition as well as structure that varies across the entire volume and with changing properties. Functionally graded materials are produced through different manufacturing processes which include centrifugal method, powder metallurgy method, and additive manufacturing technology. Additive Manufacturing (AM) is an advanced manufacturing process used to produce three dimensional objects simply by adding materials in layers using the digital image of the component. In this chapter, the production of compositionally graded composite materials using an advanced manufacturing method, laser additive manufacturing technologies, which include selective laser melting/sintering and laser metal deposition/laser material deposition (LMD) processes are reviewed and the recent research progress are also presented.
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Corrosion behaviour of laser additive manufactured titanium alloy
- Authors: Mahamood, R.M. , Akinlabi, Esther Titilayo
- Date: 2018
- Subjects: Corosion rate , Laser metal deposition , Laser Engineered Net shaping
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/290913 , uj:31589 , Citation: Mahamood, R.M. & Akinlabi, E.T. 2018. Corrosion behaviour of laser additive manufactured titanium alloy.
- Description: Abstract: The influence of process parameter on corrosion behavior of the most widely used titanium alloy-Ti6Al4V, produced using laser metal deposition process was studied. The processing parameters: scanning velocity, the powder flow rate and gas flow rate were kept at constant values of 0,005m/s, 1.44 g/min and 4 l/min while the laser power was varied between 0.8 to 3.0 kW. Electrochemical corrosion test was conducted on each of the samples produced at each set of processing parameters. The corrosive media used is the solution of sodium chloride (NaCl) desolved in deionized water. The results of this study indicate that the as the laser power was increase, the corrosion behaviour was found to be improved. The better corrosion resistance performance of the additive manufacture part can be attributed to the higher cooling rate that is associated with this type of manufacturing process. This high cooling rate results in the higher hardness of the material which could also contribute to the improved corrosion resistance behaviour.
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Corrosion resistance of heat treated Ti6Al4V in NaCl
- Authors: Omoniyi, P.O. , Akinlabi, E.T. , Mahamood, R.M. , Jen, T.C.
- Date: 2021
- Subjects: Corrosion , Heat treatment , Ti6Al4V
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/485969 , uj:44190 , DOI: 10.1016/j.cdc.2021.100780 , Citation: P.O. Omoniyi, E.T. Akinlabi, R.M. Mahamood, T.C. Jen, Corrosion resistance of heat treated Ti6Al4V in NaCl, Chemical Data Collections, Volume 36, 2021, https://doi.org/10.1016/j.cdc.2021.100780.
- Description: Abstract: Please refer to full text to view abstract.
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Influence of laser power on microhardness and wear resistance properties of laser metal deposited 17-4 PH stainless steel
- Authors: Adeyemi, A. , Akinlabi, Esther Titilayo , Mahamood, R.M.
- Date: 2018
- Subjects: Laser Metal Deposition , Laser Power , 17-4 PH stainless steel
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/290921 , uj:31590 , Citation: Adeyemi, A., Akinlabi, E.T. & Mahamood, R.M. 2018. Influence of laser power on microhardness and wear resistance properties of laser metal deposited 17-4 PH stainless steel.
- Description: Abstract: This aim of this research is to investigate the impact of laser power on the hardness and the wear resistance properties of laser metal deposited 17-4 PH stainless steel. Hardness was studied using Zwick/Roell microhardness tester and the wear resistance property was carried out using ball-on-disc Anton Paar-tribometer wear tester. The study revealed that an irregular increase and decrease in the average hardness value and wear behaviour were observed. This could be attributed to the presence of copper precipitate which was more concentrate at the overlapping region because of the reheating activity that is happening between the succeeding and preceding track layers.
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Influence of laser power on microstructure of laser metal deposited 17-4 ph stainless steel
- Authors: Adeyemi, A.A. , Akinlabi, Esther Titilayo , Mahamood, R.M. , Sanusi, K.O. , Pityana, S. , Tlotleng, M.
- Date: 2017
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/244692 , uj:25306 , Citation: Adeyemi, A.A. et al. 2017. Influence of laser power on microstructure of laser metal deposited 17-4 ph stainless steel.
- Description: Abstract: The influence of laser power on the microstructure of 17-4 PH stainless steel produced by laser metal deposition was investigated. Multiple-track of 17-4 stainless steel powder was deposited on 316 stainless steel substrate using laser metal deposition, an additive manufacturing process. In this research, laser power was varied between 1.0 kW and 2.6 kW with scanning speed fixed at 1.2 m/s. The powder flow rate and the gas flow rate were also kept constant at values of 5 g/min and 2 l/min respectively. The microstructure was studied under optical microscope and it revealed that the microstructure was dendritic in structure with finer and lesser δ-ferrite at low laser power while the appearance of coarse and more δ-ferrite are seen at higher laser power.
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Microstructural evolution of laser metal deposited 17-4 PH SS-tungsten composite with varying volume percent tungsten
- Authors: Adeyemi, A.A. , Akinlabi, Esther Titilayo , Mahamood, R.M.
- Date: 2018
- Subjects: Laser Metal Deposition , Laser Power , Microstructure
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/290972 , uj:31595 , Citation: Adeyemi, A.A., Akinlabi, E.T. & Mahamood, R.M. 2018. Microstructural evolution of laser metal deposited 17-4 PH SS-tungsten composite with varying volume percent tungsten.
- Description: Abstract: This study investigates the influence of quantity of tungsten powder on the microstructural evolution of 17-4 PH stainless steel-tungsten composite produced using laser metal deposition process. The 17-4 PH stainless steel and tungsten powders were deposited on 316 stainless steel substrate at laser power of 2600 W. The tungsten powder flow rate was varied between 0.5 rpm and 2.0 rpm while 17-4 PH stainless steel powder flow rate, the scanning speed, the gas flow rate and the laser spot size were fixed at 2.0 rpm, 0.5 m/s, 2.5 l/min and 2.0 mm respectively. Five (5) multiple track of 17-4 PH stainless steel and tungsten powder were deposited on 316 stainless steel of thickness 10 mm from different hopper at 50% overlapping percentage to produce 17-4 PH SS-W composite. During the microstructural study, it was observed that tungsten carbide has been precipitated in-situ and evenly dispersed in the 17-4 PH SS-W composite produced. SEM and EDS analysis also revealed the presence of BCC alpha (α) ferrite and FCC gamma (δ) ferrite with the presence of sigma (σ) phase precipitates.
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