The anti-corrosion properties of paints can be optimised when adequate proportion of the paint constituents are used. Effect of zinc powder addition to Villa Gloss and Silka Lux Marine Enamel paints on corrosion resistance of mild steel was studied. Quantitative Analysis and Potentiodynamic Polarisation Technique were used to evaluate the samples. The results indicate that zinc powder addition between 15 and 25 % significantly reduced the corrosion rate. The corrosion rate stabilized at approximately 0.10 mmpy when zinc powder added was above 15 %, independent of the exposure time. Potentiodynamic anodic polarization curves of the samples immersed in seawater showed that sample with 25% zinc powder addition exhibited highest corrosion potential and the least corrosion current density. Microstructural analysis of the samples also revealed the presence of pitting corrosion at the surfaces of the samples and their geometry, volume fraction and distribution vary with the zinc powder addition.Keywords: zinc powder, inhibition efficiency, potentiodynamic, weight loss, corrosion rate, pit corrosion NOMENCLATURE A1 uncoated sample. A2 sample coated with 10ml of white paint + 0% zinc powder. A3 sample coated with 10ml of red paint + 0% zinc powder. B1 sample coated with 10ml of white paint + 5% zinc powder. B2 sample coated with 10ml of red paint + 5% zinc powder. C1 sample coated with 10ml of white paint + 10% zinc powder. C2 sample coated with 10ml of red paint + 10% zinc powder. D1 sample coated with 10ml of white paint + 15% zinc powder. D2 sample coated with 10ml of red paint + 15% zinc powder. E1 sample coated with 10ml of white paint + 20% zinc powder. E2 sample coated with 10ml of red paint + 20% zinc powder. F1 sample coated with 10ml of white paint + 25% zinc powder.F2 sample coated with 10ml of red paint + 25% zinc powder. Cr corrosion rate (mmpy) Wt weight loss (milligrams) A Surface area of the sample (cm 2 ) T time of exposure of the samples in hour(s) metal density (g/cm 3 ) L length of the sample (cm) B breadth of the sample (cm) T thickness of the sample (cm)

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Dynamic response of nanosized precipitates bearing (NPB) Waspaloy, a class of superalloy, is crucial to design structural components for critical rotating applications and other severe dynamic impact predisposed applications. The focus of this study is, therefore, to investigate the compressive dynamic behaviour of NPB Waspaloy at a high strain rate under various deformation conditions. The technique of modified split Hopkinson pressure (MSHP) bar was implemented through impact deformation of Waspaloy under wide-ranging deformation temperatures (-180 - 750 oC) and strain rates of (4*103 - 7.5*103 s-1). The outcomes of the experiments divulge how to flow stress relates directly to strain rate and is inversely proportional to deformation temperatures. Work hardening rate affects NPB Waspaloy maximally at the iciest deformation temperature (-180 oC) and the highest strain rate (7.5*103 s-1) considered. Under high straining and high rate of straining deformation conditions, the rate with which work-hardening occurs is destabilized due to the thermal softening effect during deformation. It is established that when strain is constant, the flow stress dependency on the rate of straining depicts linear relation. The thermal softening effect on NPB Waspaloy is concerted at around extreme strain rate (7.5*103 s-1) and iciest deformation temperatures within -180 ~ 25 oC. Mapping of strain, strain rate and deformation temperatures representing input parameters with the resultant flow stress provide an unambiguous analytical view of the effects of dynamic impact deformation. Flow stresses at elevated temperatures are correlated directly with grain growth, mainly influenced by adopted deformation temperatures.

Most aluminum profiles' production by deep-drawing and extrusion processes require certain degree of structural homogeneity because of the segregated second-phase particles in the as-cast structure. Rolled texture and directionality in properties often give rise to excessive earring, breakout, and tears. This study investigates the effect of heat treatment (artificial aging) on the anisotropic behavior of AA6063 alloy between rolling direction (0 • ) through 90• directions. The results show significant reduction in property variability in the aged samples along the rolling direction 0• , and 90• directions compared with the as-cast samples. This gave rise to improved % elongation, impact toughness, and substantial reduction (33.3%) in hardness. These results are capable of achieving huge savings in die conditioning and replacement with improved quality and sale of deep-drawn AA6063 alloy profiles for sustained profitability.

Environmental concerns associated with synthetic plastics are detrimental and have made it very crucial to develop biodegradable polymers for commercial and industrial uses. This work investigates the biodegradability of starch (biopolymer) based bioplastics through the soil burial test (SBT) technique. The biopolymeric films were synthesized from 190 and 250 µm biopolymer particulates of manihot esculenta and triticum aestivum. Blends from each particle size were produced in varied proportions with other additives. The biopolymeric films were characterized by physical, physiochemical, thermal, and microstructural tests. The biodegradability of starch-based polymers was determined by a soil burial test for 30 days where topsoil was used as a source of microbial activity. The conventional polyethylene film was also applied to the test. The bioplastic films were observed to have cracks on the surface and became hard and brittle at the end of the testing period. The total weight loss of 46.55–63.77 % was achieved by the bioplastic films. The LDPE film showed no trace of macro-structural changes or any weight reduction throughout the soil burial test. This research concludes that bioplastic films outperformed ordinary plastic films, as they were proven to be biodegradable; and can be employed efficiently in packaging applications.