The Izod impact strength of maleic anhydride-grafted acrylonitrile butadiene styrene (MA-g-ABS) copolymer has been improved by the use of rubbery poly(ethyleneco-vinyl acetate) (EVA). The MA-g-ABS is prepared by an internal mixer using dicumyl peroxide as free radical initiator, and the grafting degree was determined using back-titration method. The amount of EVA is optimized by evaluating the Izod impact strength, tensile, and flexural properties of the samples. Addition of 6% EVA into MA-g-ABS system improved the Izod impact strength and tensile strength by 18% and 35%, respectively. The miscibility of EVA in ABS and MA-g-ABS matrices has been observed using differential scanning calorimetry and scanning electron microscopy techniques. The enhanced adhesion property exhibited by MA-g-ABS/ EVA systems promises it as a good candidate for thermoplastic coating applications on aluminum substrates.

Boiler tube failures usually result in frequent forced outages, and ultimately in costly extended outages for major tubing replacement in a plant. There are several failure modes that may occur in a boiler tube, i.e. stress-corrosion cracking, pitting, water-side corrosion, fire-side corrosion, fatigue failure, overheating, dissimilar metal weld fatigue, mechanical fatigue and erosion. In this research the failure modes of boiler and its end cracks due to the dissimilar metal weld is analyzed. Hence data are collected and explored to determine the cause of failure and as a solution ceramic ferrule is suggested. The use of ceramic ferrule in boiler tube can eliminate the crack occurrence or delay the process due to thermal properties. The prevention of crack will reduce frequent maintenance and thus the cost of operation can be minimized.

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Development of high performance titanium dioxide (Ti02) based varistor materials demands binders to improve its physical properties which will ultimately enhance its electrical performances. The material used for ceramic based varistor should exhibit good mechanical properties. As for desired mechanical properties, porosity should be minimal, high fued density, high sintered strength and small average grain size are desired. In this paper effect of PV A (binder) on Ti02 was investigated and its influence on physical, mechanical and microstructure was observed. The binder was added during ball milling and then followed by the shaping and sintering process. The samples were characterized by evaluating fued density, hardness, compressive strength and microstructure. Our studies revealed that varistor disc with higher density, hardness and strength can be produced with the use of binder.

This study investigates the effect of water absorption on the flexural strength of kenaf/ glass/unsaturated polyester (UPE) hybrid composite solid round rods used for insulating material applications. Three volume fractions of kenaf/glass fibre 20:80 (KGPE20), 30:70 (KGPE30), and 40:60 (KGPE40) with three different fibre arrangement profiles of kenaf fibres were fabricated by using the pultrusion technique and were aimed at studying the effect of kenaf fibres arrangement profile and its content in hybrid composites. The fibre/ resin volume fraction was maintained constant at 60:40. The dispersion morphologies of tested specimens were observed using the scanning electron microscope (SEM). The findings were compared with pure glass fibre-reinforced UPE (control) composite. The water absorption results showed a clear indication of how it influenced the flexural strength of the hybrid and non-hybrid composites. The least affected sample was observed in the 30KGPE composite type, wherein the kenaf fibre was concentrated at the centre of a cross-section of the composite rod. The water absorption reduced the flexural strength by 7%, 40%, 24%, and 38% of glass/UPE (control), 20KGPE, 30KGPE, and 40KGPE composites, respectively. In randomly distributed composite types, the water absorption is directly proportional to the volume fraction of kenaf fibre. At the same time, flexural properties were inversely proportional to the volume fraction of kenaf fibres. Although the influence of water absorption on flexural strength is low, the flexural strength of pultruded hybrid composites was more influenced by the arrangement of kenaf fibre in each composite type than its fibre loading.