Supporting sustainability    

by enabling higher use of lightweight aluminum

Process supports sustainability by enabling higher use of lightweight aluminum

All automakers are facing the challenge of reducing their CO2-emissions and improving their sustainability. An important building block of their strategy is weight reduction by using more lightweight materials, such as aluminum. However, the high amounts of aluminum used lead to challenges such as sludge, that need innovative process solutions.

The Henkel BONDERITE® Flex process is key in helping automakers and suppliers use more aluminum in their efforts to make their automotive products more lightweight.

Henkel Flex is a two-step metal pre-treatment process is a new variation of the traditional zinc-phosphate process. The process offers long-term sustainability, added value and higher productivity. 

Aluminum: The sludge creator

Aluminum is a highly challenging material because it is very active. When you use traditional zinc phosphate to treat aluminum, it creates large amounts of sludge in the phosphate tank. This sludge causes rough surfaces, paint defects and can lead to paint adhesion issues. Leading to time-consuming maintenance needed to remove the sludge from the process. But what about creating a new process avoiding aluminum sludge formation all together?

Solving the Aluminum sludge problem

Creating two-thirds less sludge, Henkel’s Flex process is much better to treat high amounts of aluminum than traditional zinc phosphate. The Henkel Flex process, as the term would imply, is flexible: it can go from zero to 85% aluminum without changing anything in the process. Henkel Flex has proven its superb capabilities already for several years in the industry – providing less waste and enabling our customers to run high shares of aluminum substrate through their existing pretreatment lines. The patented process has even won the Automotive News Pace Award in 2014.

Footage courtesy of ALRO N.V.

Successfully addressing the e-mobility challenge

The increasing amount of Al-components especially by the emerging electrical vehicles is an additional challenge for pretreatment lines. The video above is a prime example from one of our customers, the ALRO Group in Belgium, that successfully addressed this challenge using the Henkel Flex process to coat high volumes of large aluminum battery boxes in his existing pretreatment line, while maintaining the flexibility to also treat other substrates.


Reach out to your Henkel expert for more details on the Flex Process and our comprehensive portfolio of metal pretreatment products by visiting our dedicated page or contact us for more information.

Christian Rosenkranz

Global Market Strategy Head for Surface Treatment, Cleaners and Lubricants.

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