Corrosion of aluminium in water
Discover the various forms of aluminium corrosion in water and learn how to predict and prevent it.
From the book “Corrosion of Aluminium” by Christian Vargel.
Types of aluminium corrosion
- Uniform corrosion
- Pitting corrosion
- Intergranular corrosion
- Exfoliation corrosion
- Stress corrosion cracking
- Corrosion fatigue
- Filiform corrosion
- Crevice corrosion
- Fretting corrosion
- Water line corrosion
- Erosion and cavitation
- Microbiologically influenced corrosion
- Galvanic corrosion
Corrosion of aluminium in water
The corrosion resistance of aluminium depends on the type of water to which it is exposed.So, it differs significantly in freshwater, seawater, brackish water, etc. Many parameters come into play, most particularly:
- the type of water,
- its composition,
- the temperature, and
- the flow of water.
The types of water
The following types of water are discussed:
- Freshwaters, with a total salinity generally not exceeding 1 g/l. Rainwater, river waters and spring waters belong to this class.
- Distilled (high-purity) water, also called deionised water. It is obtained by special processing of freshwater using ion exchange resins or distillation. Its salt content is very low, in general less than 1 mg/l.
- High-purity water is devoted to specific uses: heat exchangers, chemical industry, surface treatment, etc.
- Brackish water, with a much higher salinity, on the order of a few grams per litre, but much less than seawater. Most often, this water has been pumped from a great depth, but it can also result from processes in the chemical industry or mining.
- Waste waters treated in water treatment plants. They have a low mineral content, but a very high content of organic matter in suspension. Industrial wastewater may contain a wide range of products that are dissolved or in suspension.
- Seawater, with a salinity of approximately 30–35 g/l.
Freshwater
- The physical chemistry of water
- The analysis of water
- The various forms of aluminium corrosion in natural waters
- Blackening of aluminium
- The effect of water on aluminium
- The influence of temperature
- The influence of oxygen dissolved in water
- The influence of pH
- The influence of water movement and flow rate
- Predicting the resistance of aluminium in freshwater
- Examples for the use of aluminium in contact with freshwater
- Purified water
Seawater
- Historical background
- Characteristics of seawater
- Corrosion resistance of aluminium in the marine environment
- Forms of corrosion in seawater
- Marine applications of aluminium
- Tests in artificial seawater
Brackish waters and wastewater
- Brackish waters
- Wastewater
