Duplex Surface Treatment of Pre-Electroplating and Pulsed Nanocrystalline Plasma Electrolytic Carbonitriding of Mild Steel

Abstract

Recently, new duplex surface treatments involving the use of pre-electroplating and pulsed plasma electrolytic nitrocarburizing (PPEN/C) have led to the possibility of using this material for applications usually typical for tool steels. In this work, we present results concerning the duplex treatment of preelectroplating of Cr and PPEN/C of AISI 1020 mild steel. The samples were electroplated in a plating bath. After electroplating, the samples were nitrocarburized. The effects of time and applied voltage of PPEN/C process were discussed. The samples were characterized using scanning electron microscopy (SEM), atomic force microscopy (AFM), and microhardness testing. Electroplated layers of up to 100 lm were obtained. The subsequent PPEN/C increased the surface hardness to 1200 HV 0.2 due to the formation of nitrides and carbides. Decreasing the size of nanocrystalline carbonitrides will lead to improvement of their wear resistance significantly.

Carburizing of low-melting-point metals by pulsed nanocrystalline plasma electrolytic carburizing

“…The details of treatment process and rigs can be found in refs. [9,10]. The sparks around sample is homogenized due to high frequency of applied pulsed voltage and removing the sharp edges of samples.…”

Effect of current density on distribution and roughness of nanocrystallites for duplex treatment

“…The observed carburising rates are several orders of magnitude higher than those measured in the same type of steels at near equilibrium conditions. 8 In addition, plasma electrolytic saturation has the advantage of providing close dimensional tolerance and low cost. It could be successfully used for stainless steels, commercially pure titanium and other alloys.…”

Study of anodic voltage on properties of complex nanocrystalline carbonitrided titanium fabricated by duplex treatments

“…1 Bipolar pulsed plasma electrolytic carbonitriding (BPPEC/N) technique is a relatively new group of saturation treatments, which has been used to different metals. 2 Electrolytes of this electrolytic method are ecologically friendly and non-hazardous. 3 Despite the considerable effort that has been invested into understanding the different properties of treated steels, it seems that little attention has been given to the role of BPPEC/N in wear and corrosion procedure.…”