Corrosion is damage or degradation of metals due to redox reactions between a metal and various substances in its environment which produce unwanted compounds. In everyday language, corrosion is called rubber. The most common example of corrosion is iron scraping. Corrosion is one of the main problems in the industrial world. Of course, because corrosion causes failure in the material which leads to damage to the equipment or failure in the operation which results in no small losses
Degreasing consists in the removal of any kind of grease and dirt traces from the stainless steel metalwork, before submitting it to any heat treatment or surface finishing. It is important to remove grease and dirt traces, since the presence of organic molecules, being made up essentially of carbon, may result dangerous: indeed, it may be possible that the carbon goes into the matrix material during a heat treatment, causing an aesthetic damage to the piece and mainly a local degradation of its characteristics. Enrichment in carbon may negatively affect mechanical properties of the piece, through hardening and embrittlement processes, but especially reducing its resistance to corrosion.
Degreasing is fundamental in order to prevent eventual corrosion problems or spots during pickling, polishing, grinding/silk finishing treatments. In fact, grease and oil residues may alterthe efficiency of a pickling bath. Degreasing may be carried out with organic solvents, taking advantage of the chemical principle “the similar dissolves the similar”, or with alkali solvents or water-based acids. In this second case the action is on the hydrophilic part of the compound.
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