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This study presents the investigation of friction coefficient effect on stress-strain distribution of ceramic coated aeroengine specific material substrate using explicit finite element method. Half-cylinder-on-flat contact configuration subjected to normal and tangential loading is examined. Elastic ceramic coated elastic-plastic Ti-6Al-4V and Super CMV substrates are assigned to study the influence of different friction coefficient on contact pressure, von Mises stress, tangential stress and equivalent plastic strain distribution. The outcome of present research is quite revealing that stress-strain distribution response is remarkable for sliding step which experiencing significant traction compared to normal loading step. Higher possibilities of coated substrate equivalent plastic strain (plastic deformation) are registered under higher friction coefficient cases due to substantial resistance to overcome relative to tangential motion of contacting bodies.

This study addresses characterization of ED (electrode drying) effect on WC hardfacing welding microstructure. Medium carbon steel blade which used as CD (continuous digester) blade to mix up sulphuric acid together with ilmenite ore in a digester tank as a major part of production. Microstructure of WC hardfacing, elemental composition alongside hardness analyses are executed to investigate the effect of ED (electrode drying). The ED (electrode drying) effect on microstructure and hardness values of WC hardafcing coating are characterized by SEM (scanning electron microscope) analysis and micro-Vickers hardness tester correspondingly. Results revealed that ED (electrode drying) effect less significant in the larger carbides at overall coating zone. However, the absence of ED (electrode drying) led to distribution of uniform smaller carbide in non-carbide zone. The uniform carbide distribution increases the hardness of the WC hardfacing coating.

Total hip replacement is surgical procedure which is widely performed in most of the developed countries due to rapid aging. The extensive application of titanium alloy as hip prosthesis can be seen because of its suitable properties such as good biocompatibility, light weight and high strength. However, coating or bond is required as titanium alloy ineffective to be adhered directly with human bone. Hydroxyapatite (HAp) is common coating material used to bond Ti-6Al-4V hip prosthesis with human bone. HAp-Ti-6Al-4V interface is a possible fretting wear region which is subjected to significant contact pressure. HAp-Ti-6Al-4V interface fretting fatigue delamination leads to contact pressure which can accelerate fretting wear behaviour of HAp coating. Present paper discusses the influence of delamination length and fatigue stress ratio on contact pressure distribution at interface of HAp-Ti-6Al-4V using finite element methodology. A simple two-dimensional finite element contact configuration consisting Ti-6Al-4V substrate, HAp coating and contact pad (representing bone) is employed to examine under static analysis. The finite element predicted results highlighted that contact pressure can be promoted under increased delamination length condition and stress ratio of 0.1 (tension-tension). Contact pressure can accelerate HAp coating fretting wear behaviour.

The rapid age growth in most of the developed countries leads to application of artificial joints such as knee joints and hip joints. The properties of titanium alloy such as light weight, high strength and good biocompatibility make it a suitable material for wide usage as artificial joints. However, titanium alloy cannot directly adhered with human bone; thus, bonds or coating are required. Plasma-sprayed hydroxyapatite (HAp) is widely used as a coating to bond artificial Ti-6Al-4V implants with human bone. The contact slip mainly occurs at the HAp-Ti-6Al-4V interface which also known as possible delamination interface in hip joint artificial implant. The coating fretting fatigue delamination condition can lead to contact slip at HAp coating-Ti-6Al-4V interface which will accelerate HAp coating fretting wear behavior. This paper presents the influence of normal loading, fatigue loading and delamination length on contact slip distributions at HAp coating-Ti-6Al-4V interface through finite element based methodology. A simple FE contact configuration model consist of contact pad, HAp coating and Ti-6Al-4V substrate is examined under static simulation. The predicted results revealed that lower normal load with higher maximum fatigue loading condition could promote more contact slip distribution. The contact slip is also increased with increasing delamination length. The induced contact slip can accelerates fretting wear behavior of HAp coating.

The micro-hardness and compression of recycling aluminum alloy AA6061 were investigated as a function of the different microstructure and constituent powder metallurgy method. Five specimens were selected to investigate the compression strength and microhardness. The first, as fabricated specimen (as compacted), the second was as heat treated by quenching and aging process. Three specimens were mixed with Graphite particles as a reinforcement material. Compression strength values were tested for the specimens as fabricated and heat treated which were 195 and 300 MPa, respectively. The improvement ratio was 52% for the specimen as heat treated. On the other hand, high wear resistance was given by the specimen as heat treated, whereas, the lower wear strength was at the specimen mixed with 4.5% Graphite. These results were attributed to that the wear resistance related to the microhardness value.

The micro-hardness and compression of recycling aluminum alloy AA6061 were investigated as a function of the different volume fraction and particle sizes by using powder metallurgy method. Three different groups of volume fraction and particle size were used 21.5, 50 and 78.5 % and 25,63 and 100 μm respectively. The current paper highlight on the effect of the various of particle size on the compression strength and microhardness results. The results of compression strength and micro-hardness show that the type of the higher amount of the smaller size was obtained for higher value for each of compression strength and micro-hardness 195.66 MPa and 79.796 Hv respectively.While it was the lower values on the type of the smaller amount of the smaller size (132.05 MPa and 50.369 Hv) respectively.

The thermo-mechanical fatigue (TMF) of power plant components is caused by the cyclic operation of power plant. A time-dependent plasticity model can be used to simulate the component response under cyclic thermo-mechanical loading. This paper is concerned with the modelling of thermo-mechanical behaviour of power plant steel under various loading conditions. Fully-reversed, strain-controlled tests were conducted on a parent material of P91 steel at high temperatures in order to determine material constants. A unified, Chaboche viscoplasticity model, was used to model the TMF behaviour of the steel. The multiaxial form of the Chaboche constitutive equations have been implemented in the finite element software and validated by comparing to experimental data. Simulation results have been compared with the results of anisothermal cyclic testing in order to validate the performance of the model in cyclic temperature conditions. The model’s performance under multiaxial stress conditions was investigated by testing and simulating the notched bar specimen under load-controlled conditions.

This paper presents the residual stress behaviour under various values of friction coefficients and scratching displacement amplitudes. The investigation is based on numerical solution using explicit finite element method in quasi-static condition. Two different aeroengine materials, i.e. Super CMV (Cr-Mo-V) and Titanium alloys (Ti-6Al- 4V), are examined. The usage of FEM analysis in plate under normal contact is validated with Hertzian theoretical solution in terms of contact pressure distributions. The residual stress distributions along with normal and shear stresses on elastic and plastic regimes of the materials are studied for a simple cylinder-on-flat contact configuration model subjected to normal loading, scratching and followed by unloading. The investigated friction coefficients are 0.3, 0.6 and 0.9, while scratching displacement amplitudes are 0.05 mm, 0.10 mm and 0.20 mm respectively. It is found that friction coefficient of 0.6 results in higher residual stress for both materials. Meanwhile, the predicted residual stress is proportional to the scratching displacement amplitude, higher displacement amplitude, resulting in higher residual stress. It is found that less residual stress is predicted on Super CMV material compared to Ti-6Al-4V material because of its high yield stress and ultimate strength. Super CMV material with friction coefficient of 0.3 and scratching displacement amplitude of 0.10 mm is recommended to be used in contact engineering applications due to its minimum possibility of fatigue.

High velocity oxy-fuel (HVOF) coating techniques are employed mainly to improve the service life of engineering components, which is exposed to wear, erosion, corrosion or combination of both; wear and corrosion. The aim of this study is to investigate the wear and corrosion behavior of WC-10Ni and WC-12Co coating deposited onto medium carbon steel (Cast steel BS 3100 GR A3) blade. The blade was used to stir the mixture of sulfuric acid (H2SO4) with ilmenite to produce titanium dioxide (TiO2) pigments. The microstructures of both coatings before and after wear and corrosion testing were evaluated using scanning electron microscope (SEM). Vickers microhardness testing was used to examine the coatings hardness. The three-body wear test with wet condition using silicon carbide (SiC) slurry was used to investigate the wear behavior for both coating. The experiment was based on weight loss of the sample and Archard’s law to determine the wear rate of the coating. In addition, the three-electrode electrochemical test was used to investigate the corrosion behavior of the coatings. The mixture of H2SO4 and ilmenite used as an electrolyte of the test. It is found that the wear rate will increase with increasing of the weight loss. This is consistent with decreases of the volume fraction loss and hardness of the coating. After corrosion test, it can be observed that the existence of the crack and porosity on the coating increasing the corrosion behavior of coating. With high volume fraction and hardness, WC-12Co shows higher wear resistance compared to WC-10Ni. However, the value of corrosion rate for both coating has a slight difference due to better corrosion resistance of Ni binder itself.

This paper presents the results of heat and compression effects on moisture content and water absorption properties in the manufacturing of disposable plate made from Pineapple Leaf Fiber-based material (PALF). The plate was made of PALF and sugarcane bagasse waste as an alternative to polystyrenes, designed to promote the green technology effort on food packaging material. Two different specimens were produced with different compositions of PALF/sugarcane bagasse series N2T8 ( 20 wt% of Pineapple leaf fiber and 80 wt% of sugarcane bagasse ) and series N8T2 ( 80 wt% of Pineapple leaf fiber and 20 wt% of sugarcane bagasse). The specimens were produced using a hot press machine set at compressing temperatures of 50°C, 100°C and 150°C with constant pressure of 0.024 MPa for 10 minutes. Moisture content and water absorption tests were carried out on the specimens to determine the moisture content and water absorption properties. The lower water absorption was obtained for specimen N8T2 because PALF potential to water resistance. This range of properties is expected to be good enough for the requirement of disposable plate and it has the potential as a suitable raw material for strength and lightweight in the manufacturing of disposable plates.

This paper discusses a finite element analysis of cylinder on flat contact configuration subjected to constant normal load and reciprocating tangential displacement with linear kinematic hardening models based on bi-modal Ti-6Al-4V cyclic stress-strain curves. The predicted evolution of plastic deformation such as the equivalent plastic strain, tangential plastic strain and shear plastic strain distributions on the contact region has been studied along with its respective predicted stress distributions. The effect of applied forward and backward sliding displacement movements on predicted stress and strain distributions have also been looked at. It is found that the stress distributions predicted for kinematic hardening model is similar for forward and backward movements while the predicted plastic strain distribution is increasing with reciprocating sliding movement. The predicted value keep increasing when it moves forward, backward and finally moves forward again. This is due to large strain effect of the model and its dependant on the displacement movement amount.

Sliding contact will experience wear in majority of mechanical components during their service life where it reduces the performance of the components. The capability to predict the evolution of reciprocating wear scars, such as the scar’s width and depth, would be a valuable tool when designing mechanical components. Wear scar mechanism behaviour is characterised during stabilized cycle reciprocating sliding wear test of Ti-6Al-4V investigated using pin-on-flat arrangement under variable duration of sliding. The test samples were analyzed using profilometer test, optical microscopy test, Scanning Electron Microscopy (SEM) test, Energy Depressive X-ray (EDX) test and Vickers Hardness (HV) test. Stabilised high number of cycles shows low wear rate and initiation period of low cycles produced higher wear rate.

Ti-6Al-4V is material that has the special characterisation and widely used in tribology studies. In this study reciprocating sliding test between Ti-6Al-4V pin on Ti-6Al-4V flat surface was conclude and focussed on the different contact area of pin size. The testing is run using tribometer pin-on-flat machine where the parameter set on the computer. The sample profilometry than analysed using 3D optical microscope (OM) and value of hardness get from Vickers hardness (HV) test. Due to the experiment, the contact pressure for 6.5 mm is higher than the 12 mm pin size, that brings the higher depth of wear.

Reciprocating sliding wear test of uncoated titanium alloy, Ti-6Al-4V is investigated using pin-on-flat contact arrangement of Ti-6Al-4V/Ti-6Al-4V pair under variable number of cycles at low number of cycles. The worn surfaces of the titanium alloy specimens were analyzed with the use of optical microscope (2D and 3D OM) and Vickers Hardness analysis was carried on. The pattern of the wear scar characteristics determined and the finding at the end of wear track had been focus through the presence at the end of wear track. It is suggesting an evidence of plastic deformation with the increasing in hardness value. The increase in hardness value at the end of wear track indicates increase in the plastic deformation with increasing number of cycles.

Reciprocating sliding wear test of uncoated titanium alloy, Ti-6Al-4V is investigated using pin-on-flat arrangement under variable applied normal load. The wear scar produced by the reciprocating sliding wear test is analysed by surface profile examination using 2D and 3D optical microscope (OM) and Scanning Electron Microscope (SEM). Through SEM, the energy-dispersive X-ray spectroscopy (EDX) is used to characterise the composition of the substance on the worn surface. The hardness value of the wear scar is investigated at three regions which are; worn, unworn and the end of the wear track using Micro Vickers Hardness Test. The presence of moderate oxygen composition and the increasing in hardness value at the end of wear track suggesting evidence of plastic deformation. The increase in hardness value at the end of wear track indicates increase in plastic deformation with increasing applied normal load.

The effect of surface modification due to fretting wear behaviour of coated SCMV (High Strength Alloy Steel) with interlayer is investigated by simulation using ABAQUS Software on a cylinder on flat contact configuration under gross sliding conditions. The effect of interlayer stiffness and the surface modification are analysed with the focus on the interlayer stress failures and its associated stresses behaviour. Tangential stress and shear stress are predicted to reduce with the increase of numbers of wear cycles due to the effect of contact conforming. Stresses in the interlayer are predicted to increase with the interlayer stiffness due to the function of the interlayer as the load bearer.

The fretting wear behavior of Ti-6Al-4V is studied with the focus on cyclic plasticity effect under partial slip condition. The analysis is simulated using finite element based method with a new worn surface profile model represent a given number of cycles using a cylinder-on-flat geometry. The effect of surface modification on the stresses and plastic strain distribution is studied. As the profiles become deeper and wider, the contact pressure and shear stress increase at the stick zone. Due to this increment, the accumulation of plastic strain will become more significant. This may lead to material’s ductility exhaustion that could initiate the nucleation of crack. Plastic deformation is predicted to occur in the 6000thcycle model and onwards. Overall the relationship of fretting wear and plasticity has been defined qualitatively.

This paper presents a numerical investigation on semi-elliptical surface cracks in round bars subjected to mode III loadings. Lack of information can be found in open literature regarding to the J-integral solution especially the surface crack subjected to mode III loadings. Therefore, this work investigates and analyzes crack behavior using J-integral approach. On the other hand, a mathematical model is also developed to predict the J-integral along the crack front. It is found that the J-integral can be used to predict well along the crack front. However, the prediction is strongly influenced by whether the material is elastic-or plastic dominated region.

This paper presents finite element modelling of fretting wear under partial slip conditions using combined isotropic-kinematic hardening plasticity model with the emphasized to investigate the cyclic-plasticity behaviour predicted under fretting condition. The model is based on two-dimensional (2D) cylinder-on-flat contact configuration of titanium alloy, Ti-6Al-4V. A number of wear profiles at specific number of wear cycle (6000th, 60000th, 150000th and 300000th) are simulated. Contact pressure, tangential stress, shear stress, equivalent plastic strain, tangential plastic strain and also shear plastic strain are gathered and analysed. It is found that the plastic strain response of the combined isotropic-kinematic hardening plasticity model is slightly higher compare to linear kinematic hardening plasticity model [1].

is present project investigated the impact penetration response of woven jute fiber reinforced composites subjected to wide range of low impact velocities. Hand layout woven jute fibers are thermally compressed to ensure no internal defects formed in the composites. Six layers of woven jutes are stacked together using different fiber orientations [0/q/0]s. Low impact velocities are used ranging between 5 – 20 m/s. Force-time, force-displacement and energy-time curves are obtained automatically during the impact tests. The results are then discussed with considering the composite fragmentations and failure mechanisms. It is found that 00composite orientations capable to absorb sufficiently impact energy for 5 m/s but not for velocity greater than 10 m/s. When fiber orientations used between 15 – 450, the composite impact resistance increased indicating two significant peak forces. These peak forces represent different type of failure mechanisms occurred during the striker progresses.

The fretting wear behavior of Ti-6Al-4V is studied with the focus on cyclic plasticity effect under gross sliding condition. The analysis is simulated using finite element based method with a new surface profile model represently a given number of cycles using a cylinder-on-flat geometry. The effect of cyclic plasticity on the stresses and plastic strain distribution is studied. The maximum tangential stress is predicted at the trailing edge while the maximum compressive tangential stress is predicted at the leading edge of contact area. Plasticity in shear component is significant compare to tangential component and predicted at 0th and 3000th cycles only. It is found that important to include plasticity that remains from previous cycle for better prediction of fretting wear.

Finite element analysis of a coated SCMV (high-strength alloy steel) substrate with interlayer has been studied with the emphasized of stresses behaviour predicted in the substrate region due to the fretting wear surface profiles modification. The analysis is simulated using a simple cylinder-on-flat contact geometry under gross sliding condition for a given surface profile on a specific number of fretting cycles. The effect of interlayer stiffness on the stresses predicted in the substrate region is studied. It is found that the stresses in the substrate region are generally predicted to reduce with the increase of interlayer stiffness and with the advancement of wear.

The fretting wear of coated SCMV (high-strength alloy steel) substrate with interlayer is studied with the focus on stresses associated with the coating failure under gross sliding condition. The analysis is simulated using finite element based method for a given number of cycles of worn half cylinder-on-flat geometry. The effect of interlayer stiffness on the stress distributions in the coating is studied. The maximum tensile stress at the trailing edge and the maximum compressive stress at the leading edge are reducing with increasing interlayer stiffness. The maximum shear stress at the coating-interlayer interface is predicted to have negligible effect with the change of interlayer stiffness. All the stresses are generally predicted to reduce with cycle. In general, stiffer interlayer will reduce the risk of coating failure.

Cracking phenomenon in soap production is an imminent problem. It renders the soap aesthetically unpleasing. This study attempts to find best solution to solve cracking phenomenon in premium soap production. The adopted approach is a stamping method with stretched LLDPE wrap film. The result shows that stretched LLDPE wrap film able to solve the cracking problem. The appearance of the premium transparent was improved. This paper presents the results and the SOP for stretched LLDPE film wrap for soap making industries to adopt.

Transparent soap is actually the combination of actual soap and solvent. The solvent is added into the soap solution to produce the transparent characteristic. The problem from the previous production is that tiny air bubbles were observed inside the soap resulted in less attractive appearance. Current method of producing the soap bar had taken more than 8 hours and having difficulties to take out the soap bar from the plastic mold with low production rate. It is expected that the air bubble problem can be solved using this new soup molder machine. The soap production rate is believed to increase with the invention of soap molder machine. By reducing the production time from 8 hours to 2 hours, it improve production rate significantly.

This research paper presents the possible solutions to prolong the shelf life of spicy (chili) soy sauce. The current spicy soy sauce formulation is without adding preservative which result in shorter shelf life. It is suggested to add chemical preservative to this spicy soy sauce in order to prolong its shelf life without jeopardising its prevailing taste. The proposed preservative is sodium benzoate. It is hope that by adding sodium benzoate, it can prolong the shelf life of the products from one year to two years without jeopardising the taste and quality of the products. The problem to extend the shelf life of spicy (chilli) soy sauce was 100% solved. The product could be extended to 2 years without adding any preservative (sodium benzoate) as the main raw material (soy sauce) purchased from "Kicap Jalen" had been added sodium benzoate as their preservative to prolong the soy sauce shelf life. All the physicochemical and nutritional analysis shown good results. As for the microbiological analysis, all the 3 samples shown good results on the total plate count.

Thermally conductive plastic is the composite between metal-plastic material that is becoming popular because if it special characteristic. Injection moulding was regarded as the best process for mass manufacturing of the plastic composite due to its low production cost. The objective of this research is to find the best combination of the injection parameter setting and to find the most significant factor that effect the strength and thermal conductivity of the composite. Several parameter such as the volume percentage of copper powder, nozzle temperature and injection pressure of injection moulding machine were investigated. The analysis was done using Design Expert Software by implementing design of experiment method. From the analysis, the significant effects were determined and mathematical models of only significant effect were established. In order to ensure the validity of the model, confirmation run was done and percentage errors were calculated. It was found that the best combination parameter setting to maximize the value of tensile strength is volume percentage of copper powder of 3.00%, the nozzle temperature of 195oC and the injection pressure of 65%, and the best combination parameter settings to maximize the value of thermal conductivity is volume percentage of copper powder of 7.00%, the nozzle temperature of 195oC and the injection pressure of 65% as recommended.

This establishes the effect of coating geometry with precrack on stress intensity factor (SIF) using Finite Element Simulation. The coating is assumed to be brittle and perfectly adhered to the substrate. The coating surface is loaded by a sliding cylinder across the crack, thus including normal and tangential loads. Results suggest that an increase in the pre- crack length in the coating causes the corresponding increase of the SIF, enhancing the possibility of the crack extension. A thicker coating with a long pre-crack length is predicted to continue increasing stress intensity factor (K) along the sliding path.