93 research outputs found
Evaluation of transformed layer hardness of DLC coating after friction test
No full textDiamond-like carbon (DLC) provide very excellence performance in term of
friction coefficient and wear resistance under boundary lubrication. the nano
characteristic of the transformed layer has not been studied in terms of its
hardness which is believed to have a significant effect in the tribological
performance. This study presented the scratch test of the DLC transformed
layer was obtained from the AFM scratch test that governs the friction behavior
of DLC. As a result, the hardness of the DLC transformed layer depends on the
oil temperature, where the sliding interface of DLC softened during the friction
test due to graphitization process
Effect of Surface Transformation and Transfer Film on Friction of Carbonaceous Hard Coatings
No full textEffect of Surface Transformation and Transfer Film on Friction of Carbonaceous Hard Coatings
Full text link名古屋大学Nagoya University博士(工学)doctoral thesi
Pressurised pyrolysis of rice husk
Full text linkMalaysia produces every year huge quantities of agro residue such as rice husk, palm shell, sugar cane and etc. Pusat Tenaga Malaysia reported that the estimating potential energy of biomass around 834.305 PJ in year 2002. Rice husk has a potential energy around 7.536 PJ. Raw rice husk is not suitable used as fuel due to low density, low calorific value, high volatile matter, moisture and ash content. However, these characteristics can be improved by converting it into solid fuel through pressurised pyrolysis technology. Compressing and carbonisation process is applied simultaneously in pressurised pyrolysis to produce biocoal under pressure 3-6 MPa and heating temperature of 250°C. Experiments are carried out the thermo-chemical properties, density and compressive strength of biocoals. The calorific value and density of biocoal are increased to 20.12 MJ/kg and 1150 kg/m³ respectively. The biocoal has compressive strength of 3.49 MPa
Effect of Tensile Load on Electrical Resistivity of Stretchable Conductive Ink (SCI)
Full text linkTo date, research has tended to focus on emerging Electrical Conductive Adhesive (ECA) with stretchable and flexible substrate or known as Stretchable Conductive Ink (SCI). SCI is more flexible, stretchable and multi-purpose compare with the traditional printed circuit. Limitation on the chatacreization of SCI performance especially on it electrical performane under tensile stress has motivate this study. The aim of this research is to investigate the conductivity of the conductive ink under tensile stress at different elongation. The conductive ink carbon black was used to print on the thermoplastic polyurethane (TPU) and cure in the oven at 120°C for 30 minutes. The conductive ink was clamp using in-house stretching equipment with different elongation. The resistivity was measured by four-point probe while surface structure was observed by using Axioscope 2 MAT microscope. The result shows that the resistance increased when the elongation increased. For 40mm length of conductive ink, the initial resistance is 0.562 kΩ and its become 1.217 kΩ when stretch until 18% of its initial length. The sheet resistance of the conductive ink also increased due to the defection (porosity) on the surface of conductive ink after stretching. The strain level for 40mm and 60mm also increase form 0.14 to 0.16 that cause incerase in resistance. However, since there are no crack/defection observes at 80mm after maximum elongaton, the resistance start to decrease that cause increase in SCI conductivity
Correlation analysis of biodegradable additives, temperature and loading toward tribology behaviour of musa aluminata balbisiana (MBS) oil
Full text linkIdentification of the effect of the tribological characteristics in lubricant application is a critical part of the experimental process. A correlation study is used to identify the effect of temperature, load and biodegradable additive on the coefficient of friction (COF) and specific wear (Ws) from the experimental data. Pearson correlation coefficient (r) and analysis of variance (ANOVA) are the statistical analysis used to identify the relationship between the parameters and the significant difference in response variable which are COF and Ws. Based on the result, there is a positive moderate linear relationship between temperature to both COF and Ws
with a score of r between 0.354 to 0.676. In contrast, there is a negative linear relationship between load towards COF and Ws with a -0.285 to -0.460 score of r. There is approximately no correlation with the percentage of biodegradable additives respecting COF and Ws. The result also shows that there is no significant difference between COF and Ws using ANOVA testing with a p-value is more than 0.05. This work may facilitate improvements for other researchers to identify the variable in the experimental design proces
Physiochemical Properties and Fatty Acids Profiles of Oil from <i>Musa Aluminata balbisiana</i>
No full textBanana peel wastes of Musa Aluminata balbisiana (MBS) which known as a waste, and often ignored was collected and subjected to approximate composition study. The study revealed that the peel contained 78.58% of moisture content and 0.57% of volatile content. Oil extraction of MBS was performed using soxhlet method was yielded a pale brownish oil at room temperature with extraction recovery of 62.42%. The oil was exhibited a density, specific gravity, refractive index and viscosity of 08502 kg/m3, 0.8536 kg/m3, 1.47 and 3.29 cSt respectively. Physiochemical analysis shows that, the oil contained 2.64 of free fatty acids (FFAs), 0.77 g I2/100 g of oil Iodine values (IV), 7.46 mgKOH/g of saponification value (SV), 0.52 mgKOH/g of total acid number (TAN). Fatty acids analysis showed that, the oil composed of 46% of saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) and 4% of polyunsaturated fatty acids (PUFAs). The fatty acids analysis exhibit a desirable properties to further developed as a lubricants or as a lubricant additives due to ability to provides surface protective film in tribological behavioral due to the higher percentages of SFAs.</jats:p
Interface thermal resistance and thermal conductivity of polymer composites at different types, shapes, and sizes of fillers: A review
No full textThe growing demand toward miniaturization and power device packaging required new die-attach materials with high thermal conductivity (TC). Multitudinous attention is being paid to enhance the TC of thermally conductive polymer composites as it is easy to fabricate and environmentally friendly and has low-cost processability. However, after years of extensive research, it can be concluded that reinforcing different morphologies of fillers (types, sizes, and shapes) into polymer composite creates interfacial thermal resistance (ITR) that greatly constrains the TC value. Thus, this article presents an exhaustive review in minimizing the ITR effect by optimizing the types, sizes, and shapes of the fillers used. This literature also seeks to review the use of different morphologies of fillers in single and hybrid polymer composites. It was found that hybridizing two different fillers shows remarkable TC enhancement
due to its synergistic effect and formation of three-dimensional network/conduction path. The size and shape of fillers used play a vital role in improving the TC of the polymer composite compared with the type of filler used due to more contact area created, which significantly reduces the ITR. The results presented here may facilitate improvement in the development of future work
for new die attach of the thermally conductive polymer composite
The Effect Of Temperature On The Electrical Conductivity And Microstructure Behaviour Of Silver Particles
Full text linkSilver conductive ink has been used in the electronics industry due to their potential advantages such as high electrical conductivity and thermal conductivity. However, silver needs to undergo a curing process to reduce the porosity between particles as well as to have a smooth conductive track to ensure maximum conductivity. Therefore, the effect of temperature on the electrical conductivity and microstructure were explored. The printing of silver conductive paste was executed on a polymer substrate through screen printing before analysis. Next, an electrical analysis was done to measure the conductivity by using a 4-point probes instrument, followed with microstructure and mechanical analysis which were carried out to observe the structure behaviour and hardness of silver respectively with respect to temperature. The study found that the electrical conductivity of silver increases when temperature elevated. Besides that, the microstructure of silver has a larger size with the increase in temperature, correspondingly cause the silver to have less hardness. In conclusion, temperature plays significant roles in increasing the electrical conductivity of silver
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