Improvement of the stainless steel electropolishing process by organic additives

Abstract

The infl uence of organic additives on the process of surface electropolishing of AISI 304 type steel was determined. Additives were selected in initial potentiodynamic tests pursuant to the plateau analysis on the current/potential curves. The assessment of the operational effectiveness of additives consisted in determining the relationship between surface gloss after electropolishing and the mass loss of the sample and in determining surface roughness. The applied electropolishing bath consisted of a mixture of concentrated acids: H 3 PO 4 and H 2 SO 4 , and the following organic additives were used: triethylamine, ethanolamine, diethanolamine, triethanolamine, diethylene glycol monobutyl ether and glycerol. The best electropolishing result, i.e. low roughness and high gloss of stainless steel surface with a relatively low mass loss of the sample at the same time were obtained for baths containing triethanolamine.

Recent trends in Ni(II) sorption from aqueous solutions using natural materials

“…Thanks to its peculiar physicochemical properties (resistance to very high temperatures, oxidation and corrosion, big ductile and readily in processing), nickel is used in many industrial sectors, including the paper industry, steel mills, refineries, and fertilizer factories. Increased nickel ion concentrations are also noticed as a result of the production of galvanic coatings and pickling as well as the electropolishing of stainless steels, electroforming and production of nickel-cadmium batteries and electronic equipment (Lochynski et al 2016;Lochyn ´ski et al 2019). This is particularly important issue because nickel is readily soluble at pH \ 6.5 in dilute oxidizing acids.…”

Fabrication and Characterisation of Porous Coatings Enriched with Copper on CP Titanium Grade 2 under Plasma Electrolytic Oxidation

“…In Fig. 8, the SEM pictures with two magnifications (500×, 5000×) of porous coating formed on Titanium after PEO process at voltage of 650 V DC after 3 min in 500 g/L of Cu(NO 3 ) 2 ) show clearly that with PEO treatment at 650 V, the obtained coating contains more copper than that one obtained at 450 VDC(aver. 6.3 at%).…”

“…Contemporary surface technology is frequently realized under electrochemical processing, effective with oxide layers of nanometric thickness or porous compounded layers of micrometric thickness. In view of obtaining nano-layers, the standard electrochemical polishing (EP) method [1][2][3][4][5], electropolishing in magnetic field (MEP) [6][7][8][9][10][11][12] or high-current density electropolishing (HDEP) [14,15], or High-Voltage Electropolishing (HVEP) [16], are used. Micro-layers with micro-and nanopores may be obtained by Plasma Electrolytic Oxidation (PEO), which is also described in literature as Micro Arc Oxidation (MAO) on metals, e.g.…”

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

“…As the electric load Amin increases, the bath composition changes while the values of weight loss begin to diverge from those that may be calculated from a linear proportion. The application of organic additives to process baths allows for reducing weight losses in comparison to baths without any additives 31 . The weight loss after the electropolishing process in Solution B, which contained triethanolamine, was lower than that in Solution A which did not contain this additive.…”