Processes, Features and Benefits

The Process

Pickling removes scale and other contaminants from workpieces, providing optimal preparation for subsequent processes such as electropolishing, coating, or anodizing.
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ElpoChem pickling processes efficiently treat the following metals:

- Stainless Steel
- Carbon Steel
- Copper and Copper Alloys
- Aluminum and Aluminum Alloys
- Titanium and Titanium alloys
- other Special Materials

Pickling increases components corrosion resistance . Properly treated surfaces and welds seams are metallically bright, free of scale and heat tint and exhibit a homogeneous structure.

Welded stainless steel plate, left side pickled with ElpoNox

Chemical structure of heat tint and weld seams (schematic diagram)
1st Fe2O3 layer, poor acid-solubility
2nd Fe3O4 layer, better acid-solubility
3rd FeO layer, good acid-solubility
4. base metal

Chemical pickling

In chemical pickling, pickling agents are either applied or the workpiece is immersed in a pickling bath.
The exposure time depends on material, layer thickness and concentration of the pickling solution — typically ranging from a few minutes to several hours.

The process enables uniform treatment of complex geometries and ensures a reproducible, clean surface.

Anodic Pickling

Anodic pickling achieves material removal electrochemically under direct current.
This process allows precise control of reaction intensity and is often used in high-grade stainless steel or titanium applications.

Pickling Titanium and Titanium Alloys

For Titanium and Titanium alloys (e.g. TiAl6V4, Nitinol, Niobium, Tantalum, Zirconium), ElpoChem offers high performance solutions with ChemoLux and ElpoNox Titanium Pickling Produts. The exposure time — depending on the material, temperature and concentration — ranges from 10 seconds to 5 minutes.

Areas of application of ChemoLux Titanium Pickling Products:

- Pickling, activating and deburring with defined removal rate
- Pre-treatment before electropolishing
- Activation and Cleaning before coating or anodizing processes
- Elimination of crack initiation sites, flakes, scale and particles

The result is a metallically pure, homogeneous and technically active surface with optimal passivity.

ElpoChem Pickling Products

ElpoChem provides customized pickling products for various applications:

- Pickling pastes — for economical treatment of weld seams, scale and heat tint
- Spray pickles — for large components and difficult-to-access areas
- Bath pickles — for immersion, sprinkling, pumping through or spray-chambers

All processes feature precise controllability, high process reliability and minimal emissions.

Result

Pickling is an indispensable step in producing metallically pure, corrosion-resistant surfaces.
Controlled removal of oxide layers significantly improves component quality and longevity — providing a perfect foundation for further processing and long-lasting functionality.