Engineering and Technology Journal

Brass used in heat exchanger is corroded in industrial water. The used inhibitor is extracted from horse tail herb added in different concentrations and temperature to industrial water in which heat exchanger if exposed to these conditions. Brass is studied under the above conditions using potentiodynamic polarization, scanning electron microscopy (SEM) and X-ray diffraction. Potentiodynamic polarization technique was used to evaluate the corrosion rate data. Inhibition efficiency of 92.1 % at 298 k was achieved with the addition of 1350 ppm of horse tail herb from potentiodynamic polarization measurements. Potentiodynamic curves show that the presence of extracted horse tail herb in industrial water affects both the anodic and cathodic processes, decreases the corrosion current density and shifts the corrosion potential towards more noble values; the inhibitors are mixed type inhibitors.

Metal samples such as Copper and Aluminum and alloy as Brass were prepared and machined as discs (plane sample) and as a half rings (curvature sample). The samples were polished by using metallographic paper with different grades. The micro roughness and the initial weight were measured for all samples before wear tests, and then the samples were subjected to wear testing system under lubricated condition, fixed normal load of 15N, sliding time 30 min and sliding speed of 750 rpm. During the running of wear testing system the temperature of the samples were measured .The wear rate was calculated by employing the weighing method. It is clear from the results that micro roughness values increasing leads to increase in weight loss , wear rate and the temperature of samples .The effect of sample shape on weight loss , wear rate and sample heat is also obvious when noticing that the different measurements of weight loss, wear rate and sample heat of curvature samples are higher than that of plane samples .