Kenaf/E-glass reinforced polypropylene (PP) hybrid composites with different fiber loading 20, 25 and 30 (vol. %) were fabricated using a hot compression molding. The effect of the fiber content on the tensile properties of the composites was studied. The ratio of alkali-treated kenaf fiber and untreated E-glass fiber was 20:10 (vol. %). The tensile strength and strain of the composites slightly decreased with the increase of the fiber content, but tensile modulus increased. The presence of voids and inhomogeneous distribution of the fibers led to the change of tensile properties of the composites as confirmed by scanning electron microscopy (SEM) micrographs of the tensile fracture surface.

The authors have conducted a preliminary investigation with regard to the potential to manufacture porous titanium alloys for biomedical applications using toxic-free elemental powders, i.e., Ti, Nb, Ta, Zr, in combination with the pressurised gas bubble entrapment method and in contrast to standard processing routes that generally utilise prealloyed powder containing potentially toxic elements. Elemental powder compacts were either hot isostatic pressed (HIP-ed) at 1000°C and then foamed at 1150°C or else HIP-ed at 1100°C and foamed at 1350°C. Porous α + β alloys containing up to 45 vol% of porosity in the size range 20-200 μm were successfully produced, thus highlighting the potential of this manufacturing route. It was expected that further optimisation of the processing route would allow full development of the preferred β-Ti phase (from the point of view of elastic modulus compatibility between implant and bone) with this being the subject of future work by the authors.

Optimasi parameter proses 3D printing dengan bahan PETG terhadap respon kekuatan lentur menggunakan metode Taguchi telah dilakukan. Penelitian ini menggunakan desain eksperimen orthogonal arrays L9 (3 3 ) dengan tiga parameter proses yang digunakan yaitu nozzle temperature, extrusion width, dan feed rate serta dengan tiga variasi level pada setiap parameter (240 °C, 245 °C, 250 °C, 0.3 mm, 0.35 mm, 0.4mm, 50%, 75%, 100%). Spesimen dipersiapkan sesuai dengan Standar ISO 178:2010 menggunakan mesin 3D printer Prusa-i3, kemudian diukur dimensi, massa, waktu produksi dan kekuatan lenturnya. Respon kekuatan lentur dianalisis menggunakan metode Taguchi melalui SN Ratio dan ANOVA untuk mendapatkan parameter optimalnya. Hasil penelitian menunjukkan bahwa parameter proses paling berpengaruh terhadap respon kekuatan lentur berturutturut adalah nozzle temperature, extrusion width dan feed rate dengan kombinasi parameter optimal yaitu nozzle temperature (250 °C), extrusion width (0.35 mm), dan feed rate (75%). Eksperimen konfirmasi menunjukkan bahwa kombinasi parameter optimal tersebut mendapatkan kekuatan lentur tertinggi dengan sebaran data yang kecil (52,98 ±0,65 MPa). Selain itu, semua produk yang dihasilkan memiliki dimensi sesuai dengan standar yang digunakan.

MORPHOLOGY AND TENSILE PROPERTIES OF PVA/SNAIL MUCIN NANOFIBER MEMBRANES. Snail mucin has been widely known to contain agents with wound healing properties. A preliminary research with regard to the potential to manufacture composite nanofibrous membranes of polyvinyl alcohol (PVA) and snail mucin (SM) by the electrospinning technique for wound dressing applications has been conducted. The effect of SM concentration on the morphology and tensile properties of PVA/SM nano membrane has been investigated. The PVA/SM solutions with various concentration of SM (0%, 2%, 4%, dan 6%)(w/v) were electrospun at the optimized process parameters. The morphology nanofiber membranes was observed by scanning electron microscopy and the average diameters of prepared nanofibers was determined by image analysis technique. The tensile test was conducted to examine the tensile properties of the nanofiber membranes being prepared according to ASTM D882. The PVA/SM nanofibre membrane possessing the tensile strength and tensile strain ranging between 3.48-5.37 MPa and 101.25-157.13 %, respectively were successfully fabricated. The membrane of 10% (w/v) PVA/ 2% (w/v) SM achieved the highest values of tensile strength. This phenomenon has been associated to the uniformity of fiber size diameter distribution within the membranes. It was expected that further optimization of the processing would allow development of the tensile properties compatibility requirement with this being the subject of future work by the authors.