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Full-Text Articles in Engineering
Alternative Methods To Determine The Elastoplastic Properties Of Sintered Hydroxyapatite From Nanoindentation Testing
Faculty of Engineering University of Malaya
This study introduces alternative methods to determine the elastoplastic properties of bovine-derived Hydroxyapatite (HA) porous bone graft through a set of nanoindentation tests with a Berkovich indenter. Generally, experimental data obtained from nanoindentation tests are force displacement, hardness and elastic modulus. However, to determine plastic properties such as strength coefficient and work hardening exponent of bovine HA, analytical or inverse finite element models are required. In this paper, the effect of sintering temperature on these properties of HA is studied for the range of 1000-1400 degrees C. The direct and inverse Finite Element (FE) simulation models for nanoindentation tests were …
Investigating The Surface Tribology Of Roller-Burnished Polymer Using The Fuzzy Rule-Based Approach
Investigating The Surface Tribology Of Roller-Burnished Polymer Using The Fuzzy Rule-Based Approach
Faculty of Engineering University of Malaya
Burnishing is specified as the plastic deformation cold working process applied as surface treatment and smoothing following machining to obtain a superior surface roughness finish. The present experimental study was carried out on roller-burnished polyurethane using a roller burnishing tool. An analysis was done to investigate the effect of burnishing depth, speed, feed rate, and roller width on the surface roughness of the polymer workpiece. Roughness (R-a) prediction was achieved with a fuzzy rule-based system. The results indicate 95% accuracy between the fuzzy predicted roughness values and experimental results. Link to Full-Text Articles : www.tandfonline.com/doi/abs/10.1080/10402004.2014.962205
Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang
Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang
Azman Ismail
The external surface hardness of friction stir welded aluminum alloy 6063 pipe joint was investigated in this paper. The 89mm of outside diameter pipe with 5mm of wall thickness was used as test pipe piece for this experiment on closed butt joint configuration by utilising Bridgeport 2216 CNC milling machine and orbital clamping unit specially designed to cater for this task and function. Several welded samples were produced on varying process parameters which were successfully joined by using a non-consumable tool with a flat shoulder and a cylindrical pin.
Evaluation Of Cassava Tuber Resistance To Deformation, Oladele Peter Kolawole Engr.
Evaluation Of Cassava Tuber Resistance To Deformation, Oladele Peter Kolawole Engr.
Oladele Peter Kolawole Ph.D
A study was carried out, hardness and resistant ability of cassava tuber was investigated, the study involved the use of laboratory penetrometer and a data lodger. Hand-drilling machine was fitted with a 500mm diameter blade. These devices were powered manually and by application of electricity. Forces were applied by allowing direct cutting of the tubers using rotating sharp blade. The penetrometer was used to test the strength of fresh tuber. The result obtained indicated that cassava tuber hardness increases with the reduction of moisture content. The penetration force of 5.4 Newton at 70% moisture content wet basis was recorded while …
Degradation Of Physical Properties Of Different Elastomers Upon Exposure To Palm Biodiesel
Degradation Of Physical Properties Of Different Elastomers Upon Exposure To Palm Biodiesel
A.S. Md Abdul Haseeb
Biodiesel, as an alternative fuel, is gradually receiving more popularity for use in internal combustion engines. However questions continue to arise with regard to its compatibility with elastomeric materials. The present work aims to investigate the comparative degradation of physical properties for different elastomers [e.g. ethylene propylene diene monomer (EPDM), silicone rubber (SR), polychloroprene (CR), polytetrafluroethylene (PTFE) and nitrile rubber (NBR)] upon exposure to diesel and palm biodiesel. Static immersion tests in B0(diesel), B10 (10% biodiesel in diesel), B20, B50 and B100(biodiesel) were carried out at room temperature (25 °C) for 1000 h. Different physical properties like, changes in weight …
Addition Of Cobalt Nanoparticles Into Sn-3.8ag-0.7cu Lead-Free Solder By Paste Mixing
Addition Of Cobalt Nanoparticles Into Sn-3.8ag-0.7cu Lead-Free Solder By Paste Mixing
A.S. Md Abdul Haseeb
Purpose - The purpose of this paper is to investigate the effects of addition Co nanoparticles on the characteristic properties of Sn-3.8Ag-0.7Cu solder. Design/methodology/approach - Cobalt (Co) nanoparticles were added to Sn-Ag-Cu solders by thoroughly blending various weight percentages (0-2.0 wt%) of Co nanoparticles with near eutectic SAC387 solder paste. Blending was done mechanically for 30 min to ensure a homogeneous mixture. The paste mixture was then reflowed on a hot plate at 250°C for 45 s. The melting points of nanocomposite solder were determined by differential scanning calorimetry. Spreading rate of nanocomposite was calculated following the JIS Z3198-3 standard. …
Compatibility Of Elastomers In Palm Biodiesel
Compatibility Of Elastomers In Palm Biodiesel
A.S. Md Abdul Haseeb
In recent time, environmental awareness and concern over the rapid exhaustion of fossil fuels have led to an increased popularity of biodiesel as an alternative fuel for automobiles. However, there are concerns over enhanced degradation of automotive materials in biodiesel. The present study aims to investigate the impact of palm biodiesel on the degradation behavior of elastomers such as nitrile rubber (NBR), polychloroprene, and fluoro-viton A. Static immersion tests in B0 (diesel), B10 (10% biodiesel in diesel), B100 (biodiesel) were carried out at room temperature (25 °C) and at 50 °C for 500 h. At the end of immersion test, …
Thermal Stability Of Electrodeposited Liga Ni-W Alloys For High Temperature Mems Applications
Thermal Stability Of Electrodeposited Liga Ni-W Alloys For High Temperature Mems Applications
A.S. Md Abdul Haseeb
For thermally stable LIGA materials for high temperature MEMS applications LIGA Ni-W layers and micro testing samples with different compositions (15 and 5 at% W) were electrodeposited. In order to investigate the thermal stability the Ni-W layers were annealed at different temperatures (300-700°C) and for different durations (1, 4, 16 h). Their microstructure and micro-hardness were than analysed after annealing and compared with those of as-deposited states. The observed microstructures show, in comparison to pure LIGA nickel, a small grain growth and a relatively stable structure up to 700°C. The micro-hardness values of the LIGA Ni-W layers are higher than …
The Influence Of Titanium And Cerium On Microstructure And Properties Of Fe-C-Cr-Nb Alloys, Zeljko J. Kamberovic
The Influence Of Titanium And Cerium On Microstructure And Properties Of Fe-C-Cr-Nb Alloys, Zeljko J. Kamberovic
Zeljko J Kamberovic
In this paper, the influence of titanium and cerium on the microstructure and properties of Fe- C-Cr-Nb alloys are examined, in both as-cast and heat treated state. These elements affect the crystallisation process of Fe-C-Cr-Nb alloys and the transformation of austenite during the cooling process after solidification. Titanium changed the morphology of NbC carbides. Further, in the austenite of the examined Fe-C-Cr-Nb-Ti alloys, very fine particles of precipitated secondary carbide can be seen. The alloy containing 0,28%Ti and 0,19%Ce has martensite-perlite-austenitic matrix microstructure in as-cast condition. Adding titanium and cerium to Fe-C-Cr-Nb alloys will also changed its properties, since the …
On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film
On The Nature Of The Electrochemically Synthesized Hard Fe-0.96 Mass Pct C Alloy Film
A.S. Md Abdul Haseeb
A hard Fe-0.96 mass pet C alloy with a hardness value of 810 HV has been electrochemically synthesized from a ferrous sulfate bath containing a small amount of citric acid and L-ascorbic acid. The nature of the alloy has been investigated by a number of techniques, including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Mössbauer spectroscopy, differential scanning calorimetry (DSC), and magnetic measurements. The decomposition behavior of the alloy is also studied and compared with that of thermally prepared martensite. It has been found that the electrochemically deposited Fe-C alloy exists in …