Application of response surface method for predicting electroless nickel plating

Electroless nickel plating process has been studied considering pure copper (99.99%) as a substrate material. Deposition per unit area has been considered as a response variable and individual as well as combined effects of process parameters on deposited mass have been studied. Regression analysis and Student’s t test have been used to identify the significant influencing process parameters. It has been observed that reducing agent (NaBH4), source of metal (NiCl2 · 6H2O) and temperature significantly affect the deposition. The interactions among various process parameters have also been observed to be significant. Mathematical modeling has been carried out by a second-order response surface model with central composite design (CCD) to take into account the effect of curvature in the predicted response. Equations for response surfaces have been determined for various deposition times using MATLAB software package. Most of the response surfaces show that deposition thickness increases with increased values of process parameters within the adopted range but with different rates. The test for reliability for predicting response surface equations shows that these equations give an excellent fitting to the observed values.