Aluminium alloys are extensively used in space programs for both structural and non-structural applications. As well known, the corrosion resistance of these alloys is quite limited and anticorrosion treatment is needed.

The most used treatment currently used for improving the corrosion resistance of aluminium alloys are usually chromate (CrVI-based) conversion coatings (CCC). Due to the high environmental impact of these compounds, the REACH Regulation of the European Union decided to limit/restrict the use of hexavalent chromium. A sunset date of mid-2017 has been already set.

For the time being many chromate-free alternative products are available but they have found to be significantly inferior in terms of corrosion protection performances with respect to the chromate options. In this regard there is a great need to develop high performance hexavalent chromium-free anti-corrosion coatings with low environmental impact and conformity with the EU regulations.

The European Space Agency (ESA) is currently involved in a TRP contract with Instituto de Soldadura e Qualidade (ISQ) that is currently on-going. The objective of this study is to evaluate the anticorrosion behaviour of the different alternative pre-treatments applied to the most used aluminium. The outcome of this activity will be the identification and the optimization of the most promising anticorrosion pre-treatment.

Several commercial Cr(VI) free processes were applied onto aluminium alloys (2024-T3 and 2024-T81) used in the construction of ESA spacecraft, in order to investigate their anticorrosive properties compared with Alodine 1200, a widely used conventional CCC. One of these commercial processes (PreCoat A32) presented good anticorrosion performance, even better than Alodine 1200 and these results are presented in this paper.

Salt spray resistance is included in the testing program as well as metallurgical coating evaluation that include microscopy (SEM) observations before and after testing and electrochemical impedance spectroscopy (EIS), in order to evaluate surface and microstructural modifications due to degradation mechanisms. Further studies must be performed with the this promising alternative, modifying application parameters, in order to achieve improved corrosion protection efficiency.

Key Words: Aluminium alloy, Conversion coating, Anti-corrosion coatings, SEM, EIS

Source: Whitepaper Springer.com,Journal of Coatings Technology and Research, pp 1–14, Alternative corrosion protection pretreatments for aluminum alloys

Interested in PreCoat A32 passivation or the full whitepaper? Contact chemicals@adinternationalbv.com

precoat_a32_bare_corrosion_protection

AD sponsors Groene Ster. Because sport creates the right chemistry between body and mind, AD contributes this year as a sponsor for the Groene Ster handball association from Zevenbergen. As AD Chemicals, we have the credo; Exceeding the market standard in chromium (VI) free chemical solutions. We hope that Green Star will exceed the standard in handball the upcoming season and wins the championship. We wish Groen Ster lots of sporting successes!

 

ad_chemicals_sponsort_groene_ster

One of the most important factors influencing paint adhesion and corrosion resistance is surface preparation. To ensure optimum performance and long-term environmental resistance, metal substrates must be free of organic and inorganic contaminants. To prepare a surface one can basically choose between 2 options, blasting or chemical pretreatment.

 

  1. Mechanical/Blasting – Abrasive particles (sand, grit or metal oxides) are projected against the surface with a stream of air. The character or quality of the treatment is affected by duration of the blast; shape and size of the blasting media; particle velocity; and the hardness, porosity and other substrate properties. A metal surface treatment of blasting ensures a uniformly cleaned surface and good paint adhesion but lacks corrosion resistance on the substrate.

 

  1. Chemical processes, on the other hand, utilize organic and inorganic chemicals to achieve two reactions: • Dissolve, suspend or eliminate soils and surface contaminants. • Convert metal surfaces from the essentially free metallic state into metallic compounds.New option: Combining the worlds of blasting and chemical processingCurrently, AD Chemicals, a subdivision of the Dutch AD, International launches a revolutionary new product on the global grit/sand blasting market. This product is called PreCoat F31/20 suitable for the treatment of substrate steel and PreCoat Z31/20 for the substrates aluminum and galvanized steel. PreCoat is a chemical treatment applied directly after grit/sand blasting or metallization (also referred to as metal spraying). This product portfolio is the result of an R&D trajectory of more than 8 years. PreCoat F31/20 and Z31/20 significantly improve the quality of sandblasted or metallized products.

It has two main benefits; by applying the product directly after grit/sand blasting, a conversion layer is created that substantially improves the adhesion of the painting system (suitable for wet painting and powder coating) and significantly enhances the corrosion-protection resistance properties of the paint system as a whole. The application procedure of PreCoat is very easy and can be easily integrated in every business processes.

The innovative aspect of these products is that it combines the worlds of grit/sand blasting and chemical pre-treatment.

PreCoat F31/20 and Z31/20 are based on PreCoat Z31, a product that won the Dutch Innovation Award for surface treatment, ION Borghardt Award 2016.

AD Chemicals is introducing this product on the worldwide market. The first user responses are very promising. A large blasting company in the Netherlands stated: “With this product I am able to improve to overall quality of my products and therefore offer my customers more value. It is a tool to distinguish myself in a competitive market place”

Besides that the responses from our agents in Spain and the UK are very promising.

As products are better protected against corrosion, the product lifetime increases and thereby lowers the ecological footprint. See below the pictures after 500 hours salt spray testing where the difference is demonstrated between the regular automated grit blasting process and the grit blasting process with PreCoat treatment.

precoat blasting powdercoating chemical pretreatment test results

Want to know more about this innovation? E-mail to chemicals@adinternatonalbv.com

 

PreCoat Z31 for galvanized steel: First in Europe

AD Chemicals (chemical supplier) and Weert Group (galvanizer and powder coating applicator) are introducing an innovative chromium (VI)- free pretreatment system prior to powder coating on galvanized steel (Duplex-system). Weert Group is the first galvanizer in Europe to implement this new technology that complies with both the GSB and Qualicoat (Approval No. A-119) standard.

For making this innovation possible, there has been a joint research and development trajectory of more than 8 years. The uniqueness of the PreCoat Z31 pretreatment lies in the fact that it is a 1-on-1 replacement for chromium (VI), meaning that all the qualitative properties are sustained (corrosion protection, paint adhesion, passivation). This results in a corrosion protection and paint adhesion of more than 2000 hours of NSS, a performance to be proud of. The expectation of AD Chemicals and Weert Group is that this new system will become the (global) market standard in chromium (VI) free pretreatments on galvanized steel.

 

More innovations from AD Chemicals: PreCoat F31/20 and Z31/20 for grit blasting

AD Chemicals launches a revolutionary new product on the global grit/sand blasting market. Namely, PreCoat F31/20 suitable for treatment of steel and PreCoat Z31/20 for aluminum and galvanized steel. PreCoat is a chemical treatment applied directly after grit/sand blasting or metallization(also referred to as metal spraying). It has two main benefits; by applying the product directly after blasting, a conversion layer is created that substantially improves the adhesion of the painting system (suitable for wet painting and powder coating) and significantly enhances the corrosion-protection resistance properties of the paint system as a whole. The application procedure of PreCoat is very easy and can be integrated in every business process. Furthermore it is developed in compliancy with the Qualisteelcoat, Qualicoat and GSB quality standards. The innovative aspect is that it combines the worlds of mechanical and chemical pre-treatment, enabling a longer product lifetime.

 

AD Chemcials will be present at EUROFINISH 2017.  AD Chemicals will demonstrate its new innovations for chromium(VI) free pretreatment of galvanized steel. Furthermore we will show our PreCoat F31/20 and Z31/20 for grit blasted steel.

 

eurofinish surface treatment exhibition

Eurofinish surface treatment fair 2017

Eurofinish is organized bij VOM (Belgian association for surface finishing techniques) and takes place the 10th and 11th of May 2017 in Leuven, Belgium.

EUROFINISH will be much more than an assembly of technologies. It will be a gathering of congenial entrepreneurs and a juncture for networking, a source of inspiration for the future and a nursery of new ideas. EUROFINISH is a professional niche exhibition in the field of surface treatment and focusses on following themes:

  • Creation of added value: innovative coatings with focus on durability
  • Materials technology: attention to functional and smart utilisation of materials
  • Valorisation and durability: balancing technology and environment
  • Precision & engineering:  concurrent evolution and development
  • Future oriented: know‐how and skills under one roof

Free tickets? Contact us through chemicals@adinternationalbv.com

More information: http://eurofinish.be/

Show your innovation to the coatings and ink industry

Coatings Innovation day 2017

11 April 2017, IPKW Arnhem

The success of the Coatings Innovation day from 2015 is continued in 2017! Again, there will be a large event where innovations for the coatings and ink industry will appear in the spotlight. This time the theme is ‘Inspire & Connect’. A platform and network for anyone who wants to obtain inspiration and make new connections. Take this chance to accelerate innovation projects.

AD Chemicals will be presenting PreCoat F31/20 and PreCoat Z31/20, which are specifically designed to improve corrosion protection and paint adhesion after grit/sand blasting. Recently this product was also nominated for the Dutch ION Borghardt Innovation Award.

More information, please visit: https://www.vvvf.nl/paginas/openbaar/kennis-en-diensten/innovatie/coatings-innovatiedag

 

We are introducing our newly developed material:  “reaction products of acetic anhydride and adipic acid”. This material is commonly used in the acetylation and Cross-Binding of starch based materials. We want to emphasize  that many companies are still unware that this in fact is a reactive chemical product that needs to be registered under REACH.  AD International has obtained a registration for “reaction products of acetic anhydride and adipic acid” under registration number:  01-2120115217-67-0000 This registration was accomplished in close conjunction with REACHLaw, an independent global consultancy firm, specialised in REACH registration processes. For more details click here.

From 15 until 18 March 2016 AD Chemicals proudly presented itself at ESEF the largest and most important exhibition in the Benelux area in the field of supply, subcontracting and engineering. We look forward to meeting you at our stand where we will discuss the latest innovations in metal surface pre-treatment chemicals  with you and share our passion for the application of chemicals to ensure improved adhesion, corrosion protection and cost effective processing.

We would like to invite you to visit our stand. You will find us in Hal 2, stand G023.

 

ESEF