Subscribe to our newsletter to receive the latest news and events from TWI:

Subscribe >
Skip to content

REACH Compliant Aluminium Pre-treatments

Project Code: 33541


  • Review available chromium-free conversion coating technologies for aluminium alloys and select suitable candidate processes.
  • Procurement and corrosion testing of current Cr-free conversion coating technologies, ranking them using industrially relevant key performance indicators.
  • Develop decision support tool to inform and guide industry to suitable REACH compliant surface treatments for selected applications.
  • Perform laboratory-based trials to develop innovative treatments for self-healing, chromium-free, anodised coatings.

Project Outline

This project seeks to address the current need for chromium-free aluminium alloy conversion coatings for improved corrosion resistance. There are a variety of chromium-free conversion coatings commercially available, however, there is little impartial information comparing their corrosion performance. The majority of testing that has been carried out has been performed in either an academic environment, not using commercial products, or comparing coating performance solely with Cr(VI) analogues, either chromating or anodising.

This project seeks to provide a clear understanding of the performance of alternative chromium-free conversion coatings with regards to both their corrosion resistance and self-healing capability. Technologies are expected to include phosphating, plasma electrolytic oxidation, zirconium/titanium conversion coatings, cerium conversion coatings, and chromium-free anodising. Results will be used to develop a decision support tool to guide industry in replacing chromium-based technologies.

Relevant Industry Sectors

Benefits to Industry

The project will provide industry with a clear direction as to the most promising chromium-free conversion coating methods, in order to avoid the increasingly restrictive and costly Cr(VI) based approaches.

A decision support tool will be available online to recommend the most appropriate coating technologies as replacements for chromating and chromic acid anodising in different use cases.


 Research Board Portal

For more information please email: