Spatial Distribution of Wettability in Aluminum Surfaces Treated with an Atmospheric-Pressure Remote-Plasma

Muñoz Muñoz,Calzada Calzada,Rincón Rincón

doi:10.3390/met9090937

Abstract

The use of atmospheric-pressure remote plasmas (postdischarge) sustained in argon and argon–nitrogen for the treatment of aluminum surfaces has been studied to better understand the underlying mechanisms responsible for cleaning and activating the surfaces. The effect of the gas composition, treatment distance, and speed on the hydrophilicity of commercial aluminum samples has been studied using the sessile drop method to build spatial profiles of the treated zones. In the case of argon–nitrogen postdischarges, neither the distance to the plasma end (2 < z < 6 cm) nor the treatment speed (2500 < v < 7500 m/s) had a significant impact in the spot radius of the treatment, remaining approximately constant around 6–7 mm. This result seems to indicate that the postdischarge experiments a little expansion at the exit of the tube in which the discharge was created but its action can be considered highly-directional. This fact is essential for the possible industrial implementation of the procedure described in this research. These results have been analyzed together with the composition of active species in the postdischarge by using optical emission spectroscopy, revealing that long lived nitrogen species are required to significantly increase the wettability of the aluminum surfaces.

Highlights

Among the different materials used in the industry, metals and their alloys stand out due to their outstanding properties such as thermal and electric conductivity, malleability or ductility which make them of special interest to be utilized in sectors like electronics, food packaging, automotive, aeronautics, or construction
Aluminum surfaces can be damaged by corrosion due to chlorine ions, which is of great importance during the continue exposure to environmental agents of aluminum components in construction, naval, and aerospace industries [2]
Active Species in the Discharge active species that can be used for remote surface treatment

Summary

Introduction

Among the different materials used in the industry, metals and their alloys stand out due to their outstanding properties such as thermal and electric conductivity, malleability or ductility which make them of special interest to be utilized in sectors like electronics, food packaging, automotive, aeronautics, or construction. In the development of lithium-ion batteries, it is common to use aluminum for the manufacture of the current collector, which is exposed to the pitting corrosion of the electrolytes of the battery, especially during long work cycles, like those required for their use in electric and/or hybrid cars. This deterioration can cause an increase in the impedance and self-discharge of the battery, as well as loss of its energy storage capability [1]. Aluminum surfaces can be damaged by corrosion due to chlorine ions, which is of great importance during the continue exposure to environmental agents of aluminum components in construction, naval, and aerospace industries [2]

Methods

Discussion

Conclusion