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This study examines the relationship between service quality and customer satisfaction in Ibadan Electricity Distribution Company. To achieve this, IBEDC customers residing in Ogun State were sampled to seek their opinion on their level of satisfaction with IBEDC's services. Survey research was employed which involved the distribution of questionnaires to customers. The questionnaire sought information based on the five SERVQUAL dimension of reliability, empathy, responsiveness, tangibles and assurance which were measured on a 7-point Likert scale. A total of 397 customers were surveyed with 19 SERVQUAL survey items and 3 customer satisfaction survey items. Data collected were analysed with the use of the arithmetic mean, standard deviation and Partial Least Squares Structural Equation Model (PLS-SEM) for testing the five hypotheses theorised in the study. From the study, it was established that the reliability of IBEDC does not have a significant Original Research Article

The corrosion resistance of conventional (AA2024-T3, AA6082-T6 and AA7050-T7451) and the new generation (AA2050-T84, AA2098-T351, AA2198-T8, and AA2198-T851) precipitation-hardened alloys has been studied and compared using electrochemical and non-electrochemical approaches. The AA6082-T6 was the most resistant alloy followed by the new generation Al-Cu-Li alloys, except the AA2050-T84. All the alloys exhibited pseudo-passivity, except for the AA2024-T3 alloy which presented the highest number of pitting sites per cm 2 and also exhibited the most insidious form of corrosion amongst the alloys tested. However, the alloy with the highest corrosion depth was the AA2050-T84 alloy followed by the AA2024-T3 and AA7050-T7451 alloys. Intergranular corrosion was associated with rapid rates of penetration. In addition to the microstructural features of the alloys before corrosion, the modes of localized corrosion in the alloys were also influenced by evolving microstructural features (such as re-deposited Cu) during corrosion.

As part of the efforts to produce robust, cost effective bipolar plates, it is necessary to evaluate the forming characteristics of potential materials under consideration. For this work the relationship between strain and deformation induced surface roughness was investigated for channels made from AISI 304 stainless steel and AISI 1010 mild steel that are formed using a hydroforming process. The experiment investigated the effect of channel geometry and hydroforming pressure on surface roughness of the sheet metals under consideration. It is important to state that some functional properties and manufacturing processes of metallic bipolar plates are dependent on the surface roughness of the materials. The results indicate that the final roughness of the formed part is dependent on the initial roughness of the as received sheet. Also, the results show that the surface roughness increases with increasing forming pressure and the resulting increase in strain of the sheet metal due to deformation.

Friction stir back extrusion has recently been identified as a method for manufacturing stronger, more ductile seamless tubes. However, most of the work to date has investigated tubes with low length to diameter ratios and there has been little work investigating the change in grain through the thickness of the tube wall. The current project presents preliminary results in an investigation of the effect of the stirring process on developing ultrafine grain through the tube wall. The long term goal of the project is to miniaturize the process in order to produce highly ductile microscale tubes for biomedical applicaions, microscale heat exchangers, and fuel cell manufacturing applications. Friction stir back extrusion is a variation of friction stir processing and friction stir welding in that the end of a non-cutting tool rotates against a metal work piece, heats the work piece, and creates an ultrafine grain structure. The work described here considers tool speed and diameters when forming tubes from A1100-O aluminum work pieces. It was found that for rotations varying from 750 RPM to 2000 RPM that the maximum stir zone was approximately 250 μm at the bottom of the tube and approximately 50 μm in the walls. The outside diameter of the tubes was 12.5 mm and inside diameters of 6.35 mm and 9.3mm were produced.