Application of a KorroPad on a stainless steel ring

Application of a KorroPad on a stainless steel ring

Source: BAM

At the 2017 Hannover Messe, the Bundesanstalt für Materialforschung und -prüfung (BAM) will be demonstrating the specially developed KorroPad rapid colour test that enables the surface of stainless steel to be tested quickly, easy and, above all, by nonprofessionals. This is an example of BAM’s research power in the focus area ‘Materials’.

Whether it is a car, a skyscraper or a bridge: stainless steel is used almost everywhere in our daily life. Its corrosion resistance is important so that no safety risk arises. Stainless steels can be tested non-destructively in just 15 minutes using the rapid colour test developed by BAM before they are ever used. In the meantime, companies are already using the method called KorroPad and it is already on the curriculum in vocational schools and universities.

Tiny weak spots in the steel

Stainless steel is covered by a protective chromium oxide layer, also called a passive layer. The surface is protected from further corrosion by the passive layer. If the protective layer does not form across the whole surface, undesired corrosive reactions can occur. The reasons for an incomplete protective layer are many and diverse. Errors often occur as early as during processing. Since the passive layer is not visible to the naked eye, defective material may be further processed. As a result, safety risks can arise as stainless steels are used as starting materials for the production of a wide variety of components such as anchors, dowels and hazardous goods containers and are also used in complex chemical plants.

Detecting damage earlier and faster

KorroPad can be used to test stainless steel surfaces. The rapid colour test developed by BAM reveals damage to the passive layer significantly faster compared to traditional methods. KorroPad also offers another advantage: the component can be further processed or installed at the customer's premises after the test since it is virtually non-destructive.

Three pads, each about the size of a five-cent coin, are required for each test. The pads are pressed onto the degreased and alcohol-cleaned surface and peeled off with a spatula after 15 minutes. The KorroPad ingredients have a gel-like structure composed of water and an indicator for iron ions. If the passive layer is faulty, the indicator reacts with the iron ions in the material. This response changes the indicator’s colour and blue dots appear on the pads. Each point indicates that the protective passive layer has not formed properly on the steel surface.

The process is so simple that even nonprofessionals can apply it. The pads can be ordered via the BAM Webshop.

BAM at the Hannover Messe 2017

BAM’s stand in Research & Technology Hall 2 Stand A02 provides visitors with a broad insight into the rapid colour test KorroPad.

About BAM

BAM promotes safety in technology and chemistry.
As a BMWi departmental research institute, BAM performs research, testing and offers advisory support to protect people, the environment and material goods. Its activity in the fields of materials science, materials engineering and chemistry is focussed on the technical safety of products and processes. BAM’s research is directed towards substances, materials, building elements, components and facilities as well as natural and technical systems important for the national economy and relevant to society. It also tests and assesses their safe handling and operation. BAM develops and validates analysis procedures and assessment methods, models and necessary standards and provides science-based services for the German industry in a European and international framework.

Safety creates markets.
BAM sets and represents high standards for safety in technology and chemistry for Germany and its global markets to further develop the successful German quality culture "Made in Germany“.