Abstract: Weld repair usually comprises of mechanical removal of weld part and redisposition of the filler wire using the same parameters. The defect may be removed by carbon arc gauging and grinding or machining. The strength and the microstructure of the material will changed when the repeated weld repair is applied to the material at the same area. The purpose of this study is to compare and identify the angle of distortion, hardness, and tensile strength and bend strength and to analyze the macro and microstructure between repairing method using carbon arc gauging and mechanical grinding process with the same number of repairing sequence. The result proved that repairing A36 steel increased the strength of the material itself but the ductility was decrease when the number of repair increases. It can be concluded that, the repair using carbon arc gauging can't be applied to repair weld joint for material because it's more significant to change the material process compared to mechanical grinding. Overall, the mechanical grinding technique is the most suitable practice which can serve as the suitable method for repairing the weld defect if the repaired focus area received high impact loads.

Corrosion is described as material’s destruction or deterioration because of reaction with its surrounding environment. This type of degradation represents a tremendous economic loss since so much value of loss being described. Mostly, in petroleum industry, mild steel are still the most commonly used metal to build structures. However, acid which is hydrochloric acid has been used as acidizing operation since its advantage over other mineral acid. This may cause mild steel structure susceptible to corrosion. This project is about the study of the rate of corrosion on SMAW and GMAW welded mild steel with different time of exposure. The comparison of f these two type of welded joint were subjected for microstructure analysis using SEM/EDX. Welded mild steel were prepared using SMAW and GMAW process with dimension of 100mm x 50mm x 6mm. Then, samples were inspected using NDT technique using magnetic particle testing. After that, the samples were immersed in 6 mol of HCl acid. Then, the corroded samples were cross-sectioned and were examined using SEM/EDX. The results show that, the rate of corrosion on SMAWwelded mild steel is higher compared to the GMAW welded mild steel. As the duration of exposure increase, the weight loss also increased as well as the value of the corrosion rate. This results were supported by the MPT showing that the flaws and defects on the SMAWwelded mild steel might be the cause that act as a stress raiser and thus, enhancing the corrosion degradation.

In December 2015 and usually once in a year, the population of Temerloh'spatin fish was the environmental issue gripping Pahang. The fishes, bred in special breeding cages made of y-bar steel along the riverbanks of Sungai Pahang are threatened with a massive die-off. This low water level problems becomes worsen as more forests in the upper reaches of the Ulu Jelai and Ulu Tembeling areas are cleared for timber. Instead of that, due to the low water level and high water turbidity, y-bar steel Patin fish cages facing corrosion problem in unpredicted time. Though, this paper is to investigate the impact of heavy metal and water turbidity level on corroded y-bar steel at specified location adjacent to the fish cages. In this work, samples were submerged into the Pahang river for 56 days in February 2016. The sample then must be weighing before and after being submerged. The river water samples were took out at specific time and subjected to heavy metal and water turbidity test. It was found that, the concentration of Cu and Fe and also water turbidity level that occur in water caused by fish pallet or fish food also contribute and increase the weight loss of the Y-bar.

 Abstract: Armoured military vehicle is designed to withstand the stresses impact from bullets, missiles or any explosive shells. It is applied to the vehicle in order to protect the personnel inside from enemy fire and also to protect from any threats other than deliberate attack. However, an issue arises when it comes for track link shoes of the armoured vehicle which already became problems to the designers and users of tracked vehicles. The track link problems usually related to the problems that already existed because of its excessive weight, excessive noise and vibrations, overheating of rubber track elements and road wheels, etc. All of these existing problems could leads to the failure of pin and bushing, chunking of the pads and breaking of the track links itself. Instead of that, today's tracks are much more expensive not only in terms of initial cost but also the replacement cost. Here, this paper reviews some of the failure cases and improvements of the armoured-vehicle itself. It also covers a real study on the failure assessment of the ADNAN (The Malaysian Armoured-Vehicle) Track Shoe.Index Terms: military vehicle, rubber track, pin and bushing, impact stress, vibration.