Improvement in current efficiency of electroplated Fe-Ni films prepared in citric-acid-based baths

Abstract

Fe-Ni films were electroplated in a citric-acid-based plating bath, focusing on the current efficiency of the plating process. We prepared the plating baths with various citric acid contents, and evaluated the magnetic properties of the films and the current efficiency. The film with Fe content of approximately 22 at. % was obtained by adjusting the iron sulfate content in the plating bath, and we found that the Fe-Ni films with low coercivity (<30 A/m) could be obtained in the baths with various citric acid contents. For the current efficiency, we found that the baths with low citric acid content are effective to obtain high efficiency. The bath with the citric acid content of 10 g/l showed high current efficiency (85%), and the high efficiency enables us to increase the plating rate. The maximum plating rate was 186 lm/h, and we obtained 1.3 times higher rate compared to that for our previous study. Therefore, we concluded that the bath with low citric acid content is a suitable plating bath to obtain thick Fe-Ni films in a short time. V C 2015 AIP Publishing LLC.

Effect of Ammonium Chloride in Plating Baths on Soft Magnetic Properties of Electroplated Fe–Ni Films

“…In contrast, both the current efficiency and the Fe content show almost constant values except for 0 g/L of NH4Cl, indicating that we can vary the concentration of NH 4 Cl without the change in the Fe content. The current efficiency of approximately 95% is much higher than those for our previous study (85%) [5] and other researcher's ones (60 -80%) [10][11]. Fig.2.…”

“…Since addition of the NH4Cl improves the surface condition as shown in the insets, we considered that the dramatic decrease in the coercivity is attributed to the improvement in the surface quality of the films. In our experimental conditions, the coercivity value for NaCl = 15 g/L shows much smaller than those for NaCl = 50 g/L and our previous study (broken line in Fig.2) [5].…”

“…The concentrations of FeSO 4 and NaCl were fixed at 53 and 50 g/L, respectively. In our previous study for the citric acid, both the current efficiency and the Fe content decreases with increasing the concentration of the citric acid [5]. In contrast, both the current efficiency and the Fe content show almost constant values except for 0 g/L of NH4Cl, indicating that we can vary the concentration of NH 4 Cl without the change in the Fe content.…”

“…Thus, a complexing agent is typically used for electroplating of Fe-group films. For the plating of Fe-group films, citrates are one of hopeful complexing agents [4][5], and chloride media are also often employed [6][7]. Osaka et al have been reported Co-Fe-Ni films with high saturation magnetic flux density and low coercivity using ammonium chloride (NH4Cl) [8].…”

Electroplated Fe-Co-Ni films prepared from deep-eutectic-solvent-based plating baths

“…Taking into account of industrial advantages for the electroplating methods, we have studies some electroplated magnetic-films, such as Fe-Ni, Fe-Ni-Co and Fe-Pt, prepared from aqueous solutions, and reported their magnetic properties. [1][2][3][4] Deep eutectic solvents (DESs) are expected as new solution for plating bath due to their excellent industrial advantages. [5][6][7][8] We have reported Fe, Fe-Ni and Fe-Co films prepared in DES-based plating baths, and confirmed high current efficiency of the plating process.…”