Fabrikasi Dan Penganodan Komposit Matriks Aluminium Diperbuat Daripada Serbuk Aluminium Berbentuk Kepingan Dan Gentian Pendek Alumina Saffil ™

Kajian fabrikasi dan penganodan komposit matriks aluminium (KMA) diperbuat daripada serbuk aluminium berbentuk kepingan dan gentian pendek alumina SaffilTM telah dijalankan. Fabrikasi KMA melalui kaedah metalurgi serbuk (MS) dengan menggunakan kaedah pencampuran kering dalam atmosfera nitrogen dikaji dengan menentukan tempoh pensinteran dan nilai peratusan optimum kandungan gentian pendek alumina SaffiITM. Proses penganodan asid sulfurik telah dijalankan dan objektifnya adalah untuk mendapatkan parameter kepekatan asid sulfurik, bezaupaya dan tempoh penganodan yang sesua; untuk KMA. Kandungan optimum gentian pendek alumina SaffilTM (0 hingga 25% berat) ditentukan berdasarkan ujian mikrostruktur, ujian ketumpatan dan keliangan, ujian tegangan, ujian mikrokekerasan, analisis fasa pembelauan sinar-X (XRO) dan ujian pengembangan linear (PPL). A study of fabrication and anodising on aluminium matrix composites (AMC) made from flaky aluminium powder and short fibre alumina Saffil™ was carried out. AMC fabrication by powder metallurgy methods (PM) using dry mixing and sintered in nitrogen was studied to determine the best sintering time and optimum percentage of Saffil™ alumina short fibres content. Sulphuric acid anodising process was performed and the objective is to obtain suitable parameters of sulphuric acid concentration, anodising voltage and anodising time. Characterisation on AMC included anodised also involved corrosion and wear test. The optimum SaffilH.4 alumina short fibre contents (0 to wt 25%) was determined by microstructure, density and porosity test, tensile strength, microhardness test, X-ray diffraction (XRD) analysis and coefficient of thermal expansion (CTE) analysis

Fabrikasi Dan Penganodan Komposit Matriks Aluminium Diperbuat Daripada Serbuk Aluminium Berbentuk Kepingan Dan Gentian Pendek Alumina Saffil Tm

Kajian fabrikasi dan penganodan komposit matriks aluminium (KMA) diperbuat daripada serbuk aluminium berbentuk kepingan dan gentian pendek alumina Saffil telah dijalankan. A study of fabrication and anodising on aluminium matrix composites (AMC) made from flaky aluminium powder and short fibre alumina Saffil was carried out

Fabrikasi Dan Penganodan Komposit Matriks Aluminium Diperbuat Daripada Serbuk Aluminium Berbentuk Kepingan Dan Gentian Pendek Alumina Saffil™ [TS694.2. N336 2006 f rb].

Kajian fabrikasi dan penganodan komposit matriks aluminium (KMA) diperbuat daripada serbuk aluminium berbentuk kepingan dan gentian pendek alumina Saffil™ telah dijalankan. Fabrikasi KMA melalui kaedah metalurgi serbuk (MS) dengan menggunakan kaedah pencampuran kering dalam atmosfera nitrogen dikaji dengan menentukan tempoh pensinteran dan nilai peratusan optimum kandungan gentian pendek alumina Saffil™. A study of fabrication and anodising on aluminium matrix composites (AMC) made from flaky aluminium powder and short fibre alumina Saffil™ was carried out. AMC fabrication by powder metallurgy methods (PM) using dry mixing and sintered in nitrogen was studied to determine the best sintering time and optimum percentage of Saffil™ alumina short fibres content

Effect of sintering on the physical and mechanical properties of Co-Cr-Mo (F-75)/HAP composites

This paper reports on the effects of HAP addition and sintering temperature on the microstructure and properties of the F-75/HAP composites fabricated by powder metallurgy. Co-Cr-Mo (F-75) is used in orthopedics because of its excellent biocompatibility when implanted to human or animal body. Hydroxyapatite (HAP) powders have been used as fillers because HAP is the one of the most effective biocompatible materials with similarities to mineral constituents of bones and teeth. HAP powders (chemical formula Ca10(PO4)6 (OH)2) have been added to Co-Cr-Mo alloys in composition of 0 to 10 wt. %. The mixtures were then milled, cold compacted at 550 MPa, before sintered at 1100 and 1200°C in a tube furnace. The density, porosity, microhardness and compressive strength were measured. The composites that have been sintered at temperature 1200°C showed better physical and mechanical properties than those produced at 1100°C. After sintering at 1200°C, the samples show higher density, compared with the sample sintered at 1100°C. The sample with no HAP which have been sintered at 1200°C has the highest microhardness (208.9 HV), compared with the same sample sintered at 1100°C (194.3HV). As the temperature is increased from 1100 to 1200°C, the value of compressive strength increased from 184.538 to 341.086 MPa. Microstructural analysis for line scan showed that, as the sintering temperature was increased, there was good interface bonding between HAP particles and matrix F-75

Fabrication of calcium phosphate coating on pure magnesium substrate via simple chemical conversion coating: surface properties and corrosion performance evaluations

The main objective of the current work was to fabricate calcium phosphate (CaP) coating on 99.9% purity magnesium, Mg substrate through simple chemical conversion method and evaluated the surface properties and corrosion performance of the coated substrates. The chemical conversion method was done by immersing the samples inside primary phosphating bath and followed by secondary treatment in alkaline solutions. The coated samples from the primary (PRI) and secondary (SEC) coating treatment were analyzed from morphological, topographical, and phase analysis aspects. The corrosion behaviour of the coatings inside simulated body fluid was assessed by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The PRI and SEC coated were composed of dicalcium phosphate dehydrate (DCPD) and hydroxyapatite (HA), respectively. Both of the coatings improved the corrosion resistance of the Mg substrate. The corrosion potentials, Ecorr of the coated samples becomes nobler compared to the bare substrates. EIS shows that the polarization resistance, Rp is improved about 40 and 2 times fold for PRI and SEC compared to the uncoated samples. Furthermore, PRI shows better corrosion resistance compared to SEC due to lower porosity along with thicker and better coating coverage. Keywords: Magnesium, Calcium phosphate coating, Chemical conversion coatin

Role of Metals Content in Spinach in Enhancing the Conductivity and Optical Band Gap of Chitosan Films

Blend of chitosan and spinach extract has been successfully prepared using acetic acid as a solvent medium to produce chitosan-spinach films. The conductivity measurements showed that chitosan-spinach films for all ratios of 95 : 5, 90 : 10, 85 : 15, and 80 : 20 had better conductivity than the chitosan film. The optical band gap reduced with the addition of the spinach extract into chitosan. Chitosan-spinach film with the ratio of 85 : 15 gave the best electrical properties in this work with the conductivity of 3.41 × 10−6 S/m and optical band gap of 2.839 eV. SEM-EDX spectra showed the existence of potassium, phosphorus, sulphur, iron, and oxygen in chitosan-spinach films. AFM image showed that the surface morphology of the films became rougher as the spinach incorporated into chitosan. The minerals which exist in spinach extract play a role in enhancing electrical properties of chitosan film