After blasting, inhibitor purchase these samples were ultrasonically cleaned with acetone for 20 minutes to remove any residuals, followed by rinsing with deionized water. Finally, the samples were cleaned by steam jet for 30 seconds to remove any remaining residuals.2.2. Plating SetupFor the nickel deposition, an electroplating solution containing 400g/L NiSO4?6H2O, 30g/L NiCl2?6H2O, and 30g/L H3BO4 was used. The pH level of the electrolyte solution was regulated to a value of 3.5 by adding 10% of dilute sulfuric acid to the electrolyte. The experiments were carried out in a bath with a temperature of 55��C and 1.0V electric potential to produce 0.1Amp of current under continuous agitation by a magnetic stirrer. Two pure nickel round plates of 20mm diameter �� 3mm thickness were used as anodes.

The cathode was the thin sample previously cut (5mm diameter �� 2.05mm thick) WC-6%Co substrate, which was fixed at distinct distances from each anode. Figure 1 illustrates the electroplating configuration and setup. The electrodeposition of nickel onto the substrate surface was performed at different holding times.Figure 1Schematic of the electroplating cell.2.3. CharacterizationElectroplated samples were mounted with resin and then sectioned by precision cutter for metallographic tests. The nickel coating thickness and interface were characterized by scanning electron microscope (SEM). Value of coating thickness is obtained from the average of three measurements on each SEM image.The layer thickness variation (k) between the substrate face and its circumference was calculated using (1) as ��(coating??thickness??on???surface)?1]��100%.

(1)2.4.???coating??thickness??on???circumference)????follows:k=[(coating??thickness??on???surface Deposition ParametersElectrode gap and plating time were the input variables, termed in coded form as x1 and x2, respectively. The upper and lower limit values of the input variables were chosen in order to maintain interlayer thickness greater than 2��m with adequate quality. The selected upper and lower limit values for the electrode gap were 5mm and 15mm, respectively, and for the plating time the values were 10min and 30min, respectively. The middle limit values were 10mm for the electrodes gap and 20min for the plating time.Design of experiments and results analysis were performed using commercial statistical analysis software (Design Expert 6.

0 of Stat-Ease Inc.). A three-level factorial design with two variables as the input was employed [11]. The total treatment combinations required for the design were 9 combinations (Table 1).Table 1Design layout of experiment.For determining the relationship between the input and response, Carfilzomib the collected data were analyzed using regression. In regression model, the empirical variable (response) is approximated based on a functional relationship between the estimated variable, y, and one or more input variables, x1 and/or x2.