Surface damage, metals

Surface Damage and Reaction Rates. Erosion of surfaces resulting in higher surface area and removal of inhibiting impurities are two effects of cavitation on solids in liquid media, both of which lead to increased reaction rates. The high temperatures and pressures are sufficient to deform and pit metal surfaces (even cause local melting of some metals) and to fracture many nonmetal lie solids, in particular, brittle materials. 

Industry also uses electroplating for many applications. Chromium, an extremely hard surface metal, is commonly electroplated over steel cores for heavy duty applications. Worn or damaged metal machine parts may be restored by re-plating the worn sections. 

Metals Air pollutants, SO2, and acid gases cause damage—corrosion, surface damage, loss... 

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