Many of us may be familiar with the term ‘pickling’ as a way of preserving food. So how can metals be Pickled and what is the purpose and advantages of this process?
What Is Pickling?
Pickling is a cleaning process that removes impurities from ferrous metals. Ferrous Metals include Aluminium and Aluminium Alloys, Copper, Brass, Zinc and Stainless Steels and the Pickling Solution itself is acidic in nature, most often Sulfuric Acid and Hydrochloric Acid.
The main purpose of Pickling is essentially to clean the component and remove impurities. Although it can remove some corrosive sources, it will not enhance or protect a component against corrosion in the same way that for example Anodising would. It is purely there as a way to remove Stains, Rust and Scale from a component. Quite often Pickling will be used as a pre-plating stage to ensure that the surface is ready for electro-plating or coating.
Pickling is quite often carried out in conjunction with Passivation and Oil. Pickling with Oi removes surfaces impurities from the surface and then the Oil is used to add protection against moisture in the air which prevents oxidisation. Pickling with Passivation removes those surface impurities, and then the Passivation process helps to add a layer of corrosion through promotion of a naturally occurring Oxide layer which forms a barrier.
What Silchrome Offer
Silchrome can offer Pickling as its own process or Pickle& Oil, Pickle and Passivate. Quite often Pickling will be one of the many pre-plating processes involved with plating or coating an item. Silchrome are fully ISO 9001 and 14001 certified.