This paper aims to optimize a pulsed electrophoretic deposition (EPD) process for TiO
2 films. This is accomplished by determining the optimal configuration of the coating parameters from a robust optimization perspective. The experimental study uses a composite central design (CCD) with four
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This paper aims to optimize a pulsed electrophoretic deposition (EPD) process for TiO
2 films. This is accomplished by determining the optimal configuration of the coating parameters from a robust optimization perspective. The experimental study uses a composite central design (CCD) with four control factors, i.e., the initial concentration (x
1 in g/L), the deposition time (x
2 in s), the duty cycle (x
3 in %), and the voltage (x
4 in V). The process responses that should all be maximized are the photocatalytic efficiency of the thin film (De) and three critical charges, which characterize the adhesion failure, i.e., L
C1: the load at which the first cracks occurred; L
C2: the load at which the film starts to delaminate at the edge level of the scratch track; and L
C3: the load when the damage of the film exceeds 50%. This paper compares the robust optimization design of the EPD process using two methods: the robust design of processes and products using the stochastic frontier (RDPP-SF) and the surface response and desirability function methods. The findings show that the RDPP-SF method is superior to the response surface–desirability method for the process responses De and L
C2 because of non-natural sources of variation; however, both methods perform comparably well while analyzing the L
C1 and L
C3 responses, which are subjected to pure random variability. The parameters setting for the process robust optimization are met in run 25 (x
1 = 14 g/L, x
2 = 150 s, x
3 = 50%, and x
4 40 V).
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