Behaviour of laser metal deposited Ti6Al4V/Cu composites in hank’s solution for biocompatibility properties
- Authors: Erinosho, Mutiu F. , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2016
- Subjects: Hank’s solution , Laser metal deposition , Microhardness
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/215427 , uj:21416 , Citation: Erinosho, M.F., Akinlabi, E.T & Pityana, S. 2016. Behaviour of laser metal deposited Ti6Al4V/Cu composites in hank’s solution for biocompatibility properties.
- Description: Abstract: Ti6Al4V alloy is a well-known material for biomedical application due to the very excellent corrosion resistance it possessed. Copper is an excellent antimicrobial property and has been found to stabilize the immune system of the body activities. In this present study, laser metal deposition of Ti6Al4V/Cu composites have been conducted by varying the laser power between 600 W and 1800 W while the scanning speed of 0.005 m/s and other process parameters as depicted in the experimental matrix were kept constant. Widmanstettan structures were observed in all the samples at high magnification and lose their coarseness as the laser power increases. The microhardness values of the deposited composites were varied between HV335 ± 27 μm and HV490 ± 73 μm. The surface behaviour and the morphologies of the composites were evaluated under the SEM after soaking for 2 weeks. The simulated body fluid (hank’s solution) was maintained at normal body temperature of about 37±1oC. The surfaces showed fracture topography with porous bone-like and snowflake structures.
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Characterizing the effect of processing parameters on the porosity of laser deposited titanium alloy powder
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2014
- Subjects: Laser metal deposition , Medical implants , Porosity , Processing parameters , Titanium alloy
- Type: Article
- Identifier: uj:4739 , ISSN 2078-0966 , http://hdl.handle.net/10210/11725
- Description: Laser Metal Deposition (LMD) is an additive manufacturing technique that produces parts layer by layer directly from the Computer Aided Design (CAD) file. Highly customized parts with complex shapes such as medical implants can well be manufactured using the LMD process. LMD has been used to produce a wide range of patient specific (customized) parts. Porous parts are of particular importance as medical implants because they can potentially aid the healing process and proper integration of the implant with the body tissues. In this research porous samples of titanium alloy (Ti6Al4V) were produced using the LMD process. Spherical shaped Ti6Al4V powder of particle size ranging between 150 to 200 μm was used. The effect of laser power and scanning speed on the shape, size and degree of porosity of the deposited tracks was investigated. The results showed that as the laser power was increased and the scanning speed decreased, the degree of porosity was reduced. The size of the porosity was also found to reduce as the laser power was increased.
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Effect of powder density variation on premixed Ti-6Al-4V and Cu composites during laser metal deposition
- Authors: Erinosho, Mutiu F. , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2016
- Subjects: Powder density , Laser metal deposition , Titanium alloys , Copper
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/123406 , uj:20787 , Citation: Erinosho, M.F., Akinlabi, E.T & Pityana, S. 2016. Effect of powder density variation on premixed Ti-6Al-4V and Cu composites during laser metal deposition.
- Description: Abstract: This paper reports the effect of powder density variation on the premixed Ti-6Al-4V/Cu and Ti-6Al-4V/2Cu Composites. Two sets of experiment were conducted in this study. Five deposits each were made for the two premixed composites. Laser powers were varied between 600 W and 1700 W while a scanning speed of 0.3 m/min is kept constant throughout the experiment. Investigations were conducted on the microstructures and microhardness of the laser deposited premixed Ti-6Al-4V/Cu and Ti-6Al-4V/2Cu composites. It was found that the evolving microstructures of the composites were characterised with the formation of macroscopic banding and Widmanstatten; and disappears as it grows towards the fusion zone (FZ) and this could be attributed to the changes in the distribution of heat input. Sample A2 of premixed Ti-6Al-4V/Cu composite gives the highest hardness of 393 ± 6.36VHN0.5 while sample B4 of premixed Ti-6Al-4V/2Cu composites depicts the highest hardness value of 373 ± 9.18VHN0.5.
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Effect of scanning speed and powder flow rate on the evolving properties of laser metal deposited ti-6al-4v/cu composites
- Authors: Erinosho, Mutiu F. , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2016
- Subjects: Hardness , High pfr , Laser metal deposition , Microstructure , Porosity , Volume of deposited composite
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/93307 , uj:20331 , Citation: Erinosho, M.F., Akinlabi, E.T. & Pityana, S. 2016. Effect of scanning speed and powder flow rate on the evolving properties of laser metal deposited ti-6al-4v/cu composites.
- Description: Abstract: In Laser Metal Deposition (LMD), good bonding between two similar or dissimilar materials can be achieved if the interrelationships between the processing parameters are well understood. LMD samples of titanium alloy, Ti-6Al-4V and copper, Cu were produced by varying the scanning speed and keeping other parameters constant. The deposited samples were characterized through the volume of deposited composites, microstructure, microhardness and the degree of porosity. The effect of the optimized high (powder flow rate) PFR, scanning speed varying from 0.06 m/min to 1.2 m/min and a constant power of 1kW led to a degree of porosity on the deposited composites. The varying percentages of porosities in the samples have an advance merit effect in the implantation of bones in animal and human. It was found that the existence of pores reduced as the scanning speed increases. The Vickers mirohardness was observed to increase with an increase in the scanning speed which shows an improvement in the properties of the Ti-6Al-4V/Cu composites. At low scanning velocity, the microstructure appears coarse due to the high rate of powder deposited at the same power of 1kW. The α-phase acicular microstructure decreases in size and thickness with an increase in the scanning speed. Widmanstätten structure was found in the scanning electron microscopy analyses. The results show that high PFR and low scanning speed have significantly influenced the evolving properties of the deposited composites.
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Effect of scanning speed on laser deposited 17-4PH stainless Steel
- Authors: Bayode, Abiodun , Pityana, Sisa , Akinlabi, Esther Titilayo , Shongwe, Mxolisi Brendon
- Date: 2017
- Subjects: Functionaly graded material , Laser metal deposition , Mechanical property
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/237432 , uj:24324 , Citation: Bayode, A. et al. 2017. Effect of scanning speed on laser deposited 17-4PH stainless Steel.
- Description: Abstract: Laser metal deposition (LMD) is one of the additive manufacturing technologies that is used in the production of fully dense parts layer by layer. This innovative manufacturing process has the potential to reduce the weight, time and cost of manufacturing components. It is able to process different metallic powders and also produce custom alloy or functionally graded material by consolidating different metallic powders. The purpose of this study was to investigate and discuss the structural integrity, mechanical property and microstructure of 17-4 precipitation hardened stainless steel processed by laser metal deposition. In this study, the laser scanning speed was varied while other process parameters where kept constant. Material characterization was done using optical microscopy and Vickers indentation testing. The results show that, the processed material was structurally sound and defect free. The microstructure was predominantly martensitic and the laser scanning speed was observed to have an influence on the micro-hardness of the structure.
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Exploration of microstructure and wear behaviours of laser metal deposited Ti6Al4V/Cu composites
- Authors: Erinosho, Mutiu F. , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2016
- Subjects: Dry sliding wear , Laser metal deposition , Microstructures
- Language: English
- Type: Article
- Identifier: http://hdl.handle.net/10210/215408 , uj:21415 , Citation: Erinosho, M.F., Akinlabi, E.T & Pityana, S. 2016. Exploration of microstructure and wear behaviours of laser metal deposited Ti6Al4V/Cu composites.
- Description: Abstract: This paper reports on the investigations conducted on the evolving microstructures and the dry sliding wear of the laser deposited Ti6Al4V/Cu composites. Some selected process parameters were used for the experiments. The laser powers were chosen between 1300 W and 1600 W; scanning speeds were selected between 0.30 m/min and 0.72 m/min while other parameters are as specified in the experimental matrix. It was found that all the composites produced showed good and high-quality microstructures and they exhibited very low or no fusion zones which were as a result of the selected process parameters used. The α-phase region of the composites was found to be harder than the β-phase region. During the composites cooling, the β-phase field transformed to the basal planes of the hexagonal α-phase thereby creating a lower diffusion coefficient of the α-phase as compared to the β-phase counterpart. The Ti6Al4V/Cu composite produced at a laser power of 1397 W and a scanning speed of 0.3 m/min was found to show the lowest percentage of wear volume and coefficient of friction; and happened due to the martensitic structure formed during cooling. Results obtained showed that the poor abrasive wear of titanium alloy has been improved with the addition of copper into their lattices.
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Gas flow rate and powder flow rate effect on properties of laser metal deposited Ti6Al4V
- Authors: Pityana, Sisa , Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul
- Date: 2013
- Subjects: Gas flow rate , Microhardness , Microstructure , Powder flow rate , Laser metal deposition , Additive manufacturing technology
- Type: Article
- Identifier: uj:4849 , http://hdl.handle.net/10210/12516
- Description: Tracks of Ti6Al4V powder were deposited on Ti6Al4V substrate using Laser Metal Deposition (LMD) process, an Additive Manufacturing (AM) manufacturing technology, at a laser power and scanning speed maintained at 1.8 kW and 0.005 m/s respectively. The powder flow rate and the gas flow rate were varied to study their effect on the physical, metallurgical and mechanical properties of the deposits. The physical properties studied are: the track width, the track height and the deposit weight. The mechanical property studied is the Microhardness profiling using Microhardness indenter at a load of 500g and dwelling time of 15 μm. The metallurgical property studied is the microstructure using the Optical microscopy. This study revealed that as the powder flow rate was increased, the track width, track height and the deposit weight were increased while as the powder flow rate was increased, the track width, track height and the deposit weight decreased. The results are presented and discussed in detail.
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Influence of laser power on the deposition Ti64l4V/W composite
- Authors: Ndou, Ndivhuwo , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2016
- Subjects: Heat affected zone , Laser metal deposition
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/214837 , uj:21331 , Citation: Ndou, N., Akinlabi, E.T & Pityana, S. 2016. Influence of laser power on the deposition Ti64l4V/W composite.
- Description: Abstract: In this study of laser power on deposited of Ti64l4V/W was investigated. The energy flow rates were varied while every single other parameter were kept at a steady. The evolving microstructure and the hardness of the composites were studied and reported in this study. The study established that the laser metal deposition process is suitable for producing acceptable bonding between a deposited zone and a substrate zone. The hardness values of the deposits varied from 377HV to 719HV. The laser power directly influences the hardness and the microstructure. Scanning electron microscopy (SEM) was utilised to characterise the microstructure of the composite layer formed on the surface of the Ti6Al4V substrate. The microstructure of all the composite layers delivered by the LMD procedure has upgraded properties in connection to that of the Ti64l4V substrate.
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Influence of scanning speed and energy density on the evolving properties of laser deposited Ti6Al4V/Cu composites
- Authors: Erinosho, Mutiu F. , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2015-07-01
- Subjects: Laser metal deposition , Microhardness , Titanium composites , Copper composites
- Type: Article
- Identifier: uj:5131 , ISBN 9789881404701 , http://hdl.handle.net/10210/14094
- Description: Titanium is a light metal and finds application majorly in the aerospace and bio medicals. This paper presents the influence of scanning speed and energy density on the evolving microstructure and microhardness of laser deposited Ti6Al4V/Cu composites. The laser power, powder flow rates and gas flow rates were kept constant while varying the scanning speed. From the microscopic analysis, α acicular structures were found growing from the top of the cross section of the composite and broke into the β-phase and the grain boundary of the (α+β) phase, and found to disappear gradually as the scanning speed increases. Widmanstettan was also found in all the samples. Sample S21 of energy density 240 J/mm2 deposited with a laser power of 1200 W and a scanning speed of 5 mm/secs shows the highest hardness value of 541±20 HV0.5 while Sample S27 of energy density of 48 J/mm2 deposited with a laser power of 1200 W and a scanning speed of 25 mm/secs shows the lowest hardness value of 405±12 HV0.5. This was attributed to the Cu content added and plays a vital role in stabilizing and strengthening the β-phase.
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Laser metal deposition of Ti6Al4V/Cu composite : a study of the effect of laser power on the evolving properties
- Authors: Erinosho, Mutiu F. , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2014
- Subjects: Porosity , Laser metal deposition , Titanium alloys
- Type: Article
- Identifier: http://ujcontent.uj.ac.za8080/10210/375937 , uj:4740 , ISSN 978-93-81505-62-5 , http://hdl.handle.net/10210/11726
- Description: A study of the effect of laser power was investigated over the volume of deposited composite, microstructure and microhardness. The laser power was varied between 600 and 1800 W while keeping all other parameters constant. An indication shows that the area and the volume of the deposited composites are directly proportional to the laser power employed. The volume of the deposit obtained falls between 358.6 mm3 and 1009 mm3. The microstructures were analyzed and found that the formation of the Widmanstatten structures improved the hardness of Ti6Al4V/Cu composites. The hardness values of the deposits varied between HV335 and HV490. The percentages of porosities of the samples were also presented and found to have an inverse relationship with the laser power. The results are presented and discussed.
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Laser metal deposition of titanium aluminide composites : a review
- Authors: Abdulrahman, Kamardeen O. , Akinlabi, Esther Titilayo , Mahamood, Rasheedat M. , Pityana, Sisa , Tlotleng, Monnamme
- Date: 2018
- Subjects: Titanium aluminide composites , Laser metal deposition , Additive manufacturing processes
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/291200 , uj:31618 , Citation: Abdulrahman, K.O. et al. 2018. Laser metal deposition of titanium aluminide composites : a review.
- Description: Abstract: Development of additive manufacturing (AM) from three dimensional printers with ability of producing parts having no need for tooling continue to wax stronger in the manufacturing field. Laser metal deposition, a technique in AM is usually employed to create solid components from model of computer aided design (CAD). Feeding powder supported by shielding gas employed by this technique, is injected into a melt pool produced by accurately focused laser beam on a substrate. This paper discusses some of the AM technologies available, review on laser metal deposition of titanium aluminide on other metals and alloys, relationship between the processing parameters and structural and mechanical properties
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Laser surface modification of Ti6Al4V-Cu for improved microhardness and wear resistance properties
- Authors: Erinosho, Mutiu F , Akinlabi, Esther Titilayo , Pityana, Sisa , Owolabi, Gbadebo
- Date: 2017
- Subjects: Dry sliding wear , Laser metal deposition , Microstructure
- Language: English
- Type: Articles
- Identifier: http://hdl.handle.net/10210/241797 , uj:24925 , Citation: Erinosho, M.F. et al. 2017. Laser surface modification of Ti6Al4V-Cu for improved microhardness and wear resistance properties.
- Description: Abstract: The light weight of Ti6Al4V as a titanium alloy is been amongst the properties that have been tailed for the aerospace and other industrial applications. To modify the properties of this alloy, Cu has been added to host an antimicrobial effect in the revised alloy for marine application. The LMD process on the Ti6Al4V alloy and Cu was been investigated for surface modification in order to combat the problem of biofouling in the marine industry. The investigations focused on the microstructural observations, micro-hardness measurements and dry sliding wear in the presence of 3 and 5 weight percents of Cu. The microstructure results showed that Widmanstätten microstructures were formed in all the samples and lose their robustness towards the fusion zone as a result of the transition of heat sink towards the substrate. The microhardness values of Ti6Al4V-3Cu and Ti6Al4V-5Cu alloys were greatly improved to 547±16 VHN0.5 and 519±54 VHN0.5 respectively. In addition, the behaviour of wear loss on the surface of the Ti6Al4V-Cu alloys exhibited great improvement as compared with the parent...
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Microstructure of Ti6Al4V reinforced by coating W particles through laser metal deposition
- Authors: Ndou, Ndivhuwo , Akinlabi, Esther Titilayo , Pityana, Sisa , Shongwe, Mxolisi
- Date: 2016
- Subjects: Laser metal deposition
- Language: English
- Type: Conference proceedings
- Identifier: http://hdl.handle.net/10210/214816 , uj:21328 , Citation: Ndou, N. et al. 2016. Microstructure of Ti6Al4V reinforced by coating W particles through laser metal deposition.
- Description: Abstract: The study of laser power on deposited of Ti64l4V/W was investigated. The laser metal deposition technique has proven to be a process that is sustainable. The microstructure and microhardness properties of a Tungsten powder strengthened composite coating produced via the laser metal deposition process were investigated in this study. Laser metal deposition was completed utilizing laser power of 800W, 900W, 1100W, 1000Wand 1200W. Scanning electron microscopy (SEM) and microhardness machine were used to characterise the microstructure and hardness of the composite layer formed on the surface of the Ti6Al4V substrate. The microstructures of all the composite layers produced by the Laser Metal Deposition process were enhanced relative to those of the Ti64l4V substrate.
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Microstructures and dry sliding wear characteristics of the laser metal deposited Ti6Al4V/Cu composites
- Authors: Erinosho, Mutiu F. , Akinlabi, Esther Titilayo , Pityana, Sisa
- Date: 2015
- Subjects: Dry sliding wear , Laser metal deposition , Microstructures , Titanium composites , Copper composites
- Type: Article
- Identifier: uj:5139 , http://hdl.handle.net/10210/14106
- Description: This paper reports on the investigations conducted on the evolving microstructures and the dry sliding wear of the laser deposited Ti6Al4V/Cu composites. Some selected process parameters were used for the experiments. The laser powers were chosen between 1300 W and 1600 W; scanning speeds were selected between 0.30 m/min and 0.72 m/min while other parameters are as specified in the experimental matrix. It was found that all the composites produced showed good and high-quality microstructures and they exhibited very low or no fusion zones which were as a result of the selected process parameters used. The composite produced at a laser power of 1397 W and a scanning speed of 0.3 m/min was found to show the lowest percentage of wear volume and coefficient of friction; and happened due to the martensitic structure formed during cooling. Results obtained showed that the poor abrasive wear of titanium alloy has been improved with the addition of copper into their lattices.
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The role of transverse speed on deposition height and material efficiency in laser deposited titanium alloy
- Authors: Mahamood, Rasheedat M. , Akinlabi, Esther Titilayo , Shukla, Mukul , Pityana, Sisa
- Date: 2013
- Subjects: Additive manufacturing , Laser metal deposition , Material efficiency , Titanium alloy
- Type: Article
- Identifier: uj:4895 , http://hdl.handle.net/10210/12609
- Description: The most commonly used aerospace titanium alloy, Ti6Al4V, was deposited on Ti6Al4V plate of dimension 72 x 72 x5mm. The laser power of 3 kW, powder flow rate of 1.44 g/min and gas flow rate of 4 l/min were used throughout the deposition process. The transverse/ scanning speed was varied between 0.005 to 0.095 m/sec according to established result of the preliminary study that produces full dense and pore free deposits. The mass of the deposited powder was obtained by weight the substrate before deposition and reweighing after deposition. The substrate and the deposits were thoroughly cleaned using wire brush and acetone to remove unmelted powder particles from the surface of the substrate and the deposit. The height and width of the deposits were measured with Venier Caliper and the material efficiencies were determined using developed equations. The effect of the scanning speed on the material efficiency and deposit height were extensively studied and the results showed that for the set of processing parameter used in this study the optimum scanning speed is approximately 0.045 m/sec.
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