Investigating Optimum Parameter Required for Drilling Mild Steel Using Response Surface Methodology (Published)
The study investigated on optimum parameters required for drilling mild steel using Response Surface Methodology (RSM) based on L9-A 34-2 fractional factorial design. The mild steel workpiece is of dimension of 200 mm by 80 mm with a thickness of 1.5 mm. The study employed the following process parameters namely, cutting speed, feed, depth of cut and tool for minimizing surface roughness of mild steel. Vertical pillar drilling machine of METALIK PK203 model was used for the drilling operation and coupling ultrasonic thickness meter of TM-8810 model was also used to measure the surface roughness of the workpiece after drilling. Analysis of Variance (ANOVA) was carried out to test for the significant level of the process parameters for optimizing surface roughness. The findings revealed that the process parameters has a high significant effect in influencing the response variable at 5% significant level and that optimum process parameters can be achieved at an intermediate level during drilling operation. The findings also revealed that there exist a good agreement between the estimated and experimental results based on the mathematical model formulated.
This paper presents a corrosion rate model for mild steel in hydrochloric acid. A non-linear corrosion rate equation was developed, validated and used to relate the acid point, pH of hydrochloric acid as corrosive medium for mild steel to other variables like corrosion rate and substrate immersion period. The inhibitor used is Sinclair synthetic paint – an organic inhibitor. The effect of variables on corrosion rate has been investigated using non-linear regression analysis. The derived model is an exponential decay function of two input factors. The coefficient of correlation between the calculated and experimental data indicates good performance of the derived model.
Investigation of the Corrosion Inhibition of Mild Steel in Acidic Medium by Extract from Citrullus Lanatus Rind (Published)
Corrosion Inhibition of mild steel in acidic medium by ethanol extract of citrullus lanatus plant has been studied using weight loss method. The result of the study revealed that different concentrations of the extract of citrullus lanatus inhibited mild steel corrosion in 0.2M concentration of hydrogen tetraoxosulphate VI solution. The inhibition ability of the rind extract is attributed to the presence of the photochemical in the extracts. Result for weight loss also revealed that inhibition efficiency increased with increasing inhibitor concentration. Adsorption study revealed that adsorption of the extract of citrullus lanatus on mild steel surface occurred according to Langmuir adsorption isotherm.