A multi-factorial mathematical model for the selection of electropolishing parameters with a view to reducing the environmental impact

Abstract

Electrochemical metal processing is a process that generates harmful pollution. An important goal often disregarded by researchers is not only the achievement of the best possible quality of electropolished surface, but also minimising the load of metal ions in the wastewater generated in the process. The conducted experiments on the electropolishing of stainless steel in laboratory conditions, varied time, temperature and current density conditions, as well as process bath contamination (ranging from 0 to 6% Fe mass) allowed us to develop a multi-factorial mathematical model. This model offers the possibility of being able to select the process parameters recommended for achieving the desired effects. It takes into account such surface quality parameters as roughness and gloss, process duration and current density that determine power consumption, as well as the weight loss of the electropolished element that influence the rate of contamination in processing baths and wastewater. The study presents the composition of a passive film of stainless steel after the electropolishing process at the initial and final stages of the process bath’s exploitation. The results obtained from XPS tests were then correlated with the results of corrosion tests and resistance to pitting corrosion in the environment of 0.1 M NaCl.

Evaluation of Electropolishing Characteristics of 316L Stainless Steel Tube in Contaminated Electrolyte

“…1(c) and (d) show the ph and specific gravity of each electrolyte, and it is confirmed that the ph and specific gravity of each electrolyte increase as the usage time of the electrolyte increases. since the electrolyte used for a long time has a high metal ion concentration, the amount of hydrate formed during the electropolishing process also increases [15]. These hydrates were accumulated in the electrolyte in the form of sludge, and the ph and specific gravity increased as impurities in the specimen were mixed with the electrolyte during electropolishing.…”

The efficiency of removing heavy metal ions from industrial electropolishing wastewater using natural materials

“…One example is the electroplating industry which releases wastewater mainly from the production and processing of metal products. One of the techniques used to treat stainless steels is electropolishing [10][11][12][13][14] . This process is designed to change the surface properties of an object in order to improve its aesthetic value by smoothing and making the surface glossy and at the same time increasing its corrosion resistance 12,[15][16][17][18][19] .…”

“…One of the techniques used to treat stainless steels is electropolishing [10][11][12][13][14] . This process is designed to change the surface properties of an object in order to improve its aesthetic value by smoothing and making the surface glossy and at the same time increasing its corrosion resistance 12,[15][16][17][18][19] . This method has many applications including food, automotive, and medical industries [20][21][22] .…”