Corrosion protection

Corrosion is the gradual destruction of materials (mostly metals) as they are converted, through chemical or electrochemical reaction with their environment, into a more chemically stable form.

Corrosion can occur in many forms: Brown rust on steel is the most well-known one. This process is heavily influenced by environmental circumstances such as oxygen, humidity and temperature. As corrosion is a gradual process, it occurs in different phases.

When the 'right' circumstances for corrosion are present, an unprotected steel surface will start to show flash rust within seconds. This can happen in a pre-treatment line between the subsequent cleaning and surface treatment steps. If the circumstances do not change, corrosion will continue until the object is fully deteriorated. To prevent corrosion it is necessary to apply corrosion protection; this prevents the chemical and electrochemical processes from taking place by forming a barrier between the metal substrate and the environmental elements that are causing the corrosion.

There are two main categories of corrosion protection: permanent corrosion protection and temporary corrosion protection. The first group consists of all methods for protecting the substrate for at least its intended service life. This can include paint, powder coating, anodising (in the case of aluminium) and galvanising. The second group includes all technologies that provide a temporary protective layer during the production process or transport and warehousing.

Interoperational corrosion protection (in-process protection)

Flash rust must be avoided after cleaning metal parts in a production process. To achieve this it is necessary to consider a range of variables such as the time between the different stages, the pH of the previous stage, application methods (immersion, spray, manual), removability of the protector in the next stage, water quality and so on. The Henkel technical service team can work with customers to help find the right solution that fits perfectly with the application.

Storage / warehousing

Here the required protection time and the environmental conditions (often temperature and humidity) are the main concerns. There are several corrosion protectors in the BONDERITE portfolio with protection times that vary from a few hours up to six months.

Transport

Here too the environmental circumstances in which the products are being kept are crucial for temporary corrosion protection. The challenge, however, is that these conditions change frequently while goods are being transported. Humidity, the amount of salt (especialy for goods transported by sea), temperature and so on can vary widely over a single journey.

BONDERITE^® offers a complete portfolio of temporary corrosion protectors that can provide reliable protection under these changing conditions and compatibility with corrosion protection products, such as VCI technologies (volatile corrosion inhibitor).

Henkel supplies a wide range of BONDERITE^® temporary corrosion protection products. Each is designed for a specific function; together they offer customers the corrosion protection they need throughout their processing and continuing through transport and storage to ensure that products can be delivered to end users in perfect condition.

BONDERITE^® products from Henkel provide temporary corrosion protection for almost all metallic products with protection times ranging from a few hours to six months. For more information and to discuss your specific needs, please contact our sales department.

BONDERITE^® coating processes provide outstanding performance because they are innovative, reliable and sustainable. They provide manufacturing benefits to customers through simplified coating processes and improved corrosion resistance. This provides customers with higher value products while meeting the stringent environmental requirements of today and tomorrow.