Comparative study of platinum electroplating to improve micro gold electrode arrays with LCP laminate

Decoding the cellular network interaction of neurons and glial cells are important in the development of new therapies for diseases of the central nervous system (CNS). Electrophysiological in vivo studies in mice will help to understand the highly complex network. In this paper, the optimization of epidural liquid crystal polymer (LCP) electrodes for different platinum electroplating parameters are presented and compared. Constant current and pulsed current electroplating varied in strength and duration was used to decrease the electrode impedance and to increase the charge storage capacity (CSCC). In best cases, both methods generated similar results with an impedance reduction of about 99%. However, electroplating with pulsed currents was less parameter-dependent than the electroplating with constant current. The use of ultrasound was essential to generate platinum coatings without plating defects. Electrode model parameters extracted from the electrode impedance reflected the increase in surface porosity due to the electroplating processes.

Microstructure Investigation of Aluminide Coatings after Platinum Modification Deposited by CVD Method on Inconel 713 LC Ni-Base Superalloy

In the present study, microstructure investigation of aluminide coatings after platinum modification deposited by CVD method on Inconel 713 LC Ni-base superalloys were performed. The platinum coatings 3 and 7 m thick were deposited by electroplating process. The diffusion treatment of platinum electroplating coatings at the temperature 1050 °C was carried out for 2h. The low-activity CVD aluminizing of heat treated coatings at the temperature 1050 °C was conducted for 8 h. On the grounds of the obtained results it was found that microstructure of diffusion treated platinum electroplating coatings 3 m and 7 m thick consisted of two phases: γ-Ni and (Al0.25Pt0.75)Ni3. The low activity CVD aluminizing of diffusion treated platinum electroplating coatings 3 and 7 m thick enables the diffusion coating obtaining. The main constituent of aluminide coatings was (Ni,Pt)Al phase.

Improved Pt Aluminide Coatings Using CVD and Novel Platinum Electroplating

Chemical vapor deposition (CVD) is an old coating technology, but it was not successfully utilized to aluminize gas turbine hardware until recently (1989). In CVD aluminizing, the use of multiple, independently controlled, low temperature, external, metal halide generators combined with computer control of all process variables gives flexibility and consistent quality that is not possible with any other aluminizing process. It has been shown that harmful coating impurities (such as sulfur and boron etc.) can be transported to a coating from a high temperature aluminum source in the coating chamber during aluminizing. Representative processes include: pack cementation, above the pack, SNECMA, and high activity CVD. In contrast, it has also been demonstrated that CVD low activity aluminizing removes harmful impurities (S, P, B & W etc.) from the coating during deposition. Furthermore, clean, low activity coatings (simple aluminide MDC-210 or platinum modified MDC-150L) have been shown to exhibit superior oxidation resistance compared to similar coatings made by other aluminizing processes. A second significant source of impurities in platinum modified aluminide diffusion coatings is electroplating, that is, plating bath components (S, P, CI, K, Ca etc.) are codeposited with the platinum, and these impurities can have either a beneficial (K&Ca) or a detrimental (S,P&Cl) influence upon the oxidation resistance of the product coating. The results of investigations on the transport of impurities during aluminizing and electroplating, plus the influence of these impurities on oxidation resistance of the product coatings will be presented and discussed.