Open a window to worry-free surface treatment of extruded aluminum and galvanized steel construction parts

 

Why do manufacturers choose aluminum?

As manufacturers and customers continue demanding more sustainable solutions in the materials and products they use, aluminium remains a popular choice for many applications because of the environmentally friendly benefits it delivers. Aluminum is:

  • Easy to process: The malleability of aluminum allows it to be shaped into everything from bicycle frames and boat hulls to computer cases and kitchen utensils
  • Lightweight: In comparison to steel, aluminum measures one-third the weight and can absorb twice the crash energy
  • Easy to recycle: Americans alone recycle about 120,000 aluminum cans every minute.

Addibond™ can be used to promote paint adhesion onto electro-galvanized and hot-dip galvanized steel

 

What are the trends in the metal treatment market?

Analysts forecast dynamic growth rate for the surface treatment market. It is expected to reach more than $8 billion by 2023, with a compound annual growth rate (CAGR) of nearly 8 percent from 2017 to 2023. This market includes cleaners, etchers, de-smutters, conversion and passivation formulations, and sealants, any of which can be combined to improve paint adhesion, corrosion resistance, wear resistance, solderability and tarnish resistance. Considered substrates are Aluminium alloys, electro-galvanized steel, hot-dip galvanized steel, mild steel, Magnesium, Titanium, etc ...     

These market trends are driven by the search for new, eco-friendly solutions, such as boosting Zirconium-based conversion coatings or formulating HF-free cleaners and conversion treatment and higher demand in key industries, including:

  • Construction, where aluminium plays a major role due to its good environmental footprint
  • Automotive, and the growing use of aluminium intensive car bodies, for fully electric vehicles
  • Aerospace, and its increasing need for treating the surfaces of specific grades of steel and aluminium

Boost adhesive bonding and paint adhesion

Solvay developed the Addibond™ range of specialty additives to improve adhesive bonding and paint adhesion on organic (paint, adhesive) to metal (aluminium alloys, electro galvanized and hot-dip galvanized steel) and plastic to metal (Aluminium and PolyEtherEtherKetone - PEEK). Addibond™ additives contain two types of functional monomers — one that anchors to a metallic surface and the other that reacts with the top organic layer (paint, adhesive, etc.) The end result is a truly bonded layer that sits between the metal surface and the final organic layer.

 

Potential shorter processing time for manufacturers

The Addibond™ range simplifies the manufacturing process by allowing cleaning and etching to occur in a single step with no need for rinsing of aluminium surfaces. Treated metal can simply dry in place when Addibond™ is used in the conversion bath. Addibond™ also can be used in the final rinse to avoid changes to the manufacturing process and/or eliminate compatibility issues with any conversion bath already in place. This is true for aluminium alloys as well as electro-galvanized and hot-dip galvanized steel.

 

Improve cost in use during processing

For aluminium surfaces, Addibond™ can be used at a low dosage, typically 200 ppm or 0.02% or 0.2 g/l. Addibond™ is less sensitive to water (when compared to the classical benchmark) and also improves bath stability.  

 

Improve conversion treatment performance and process durability

The Addibond™ range boosts performance in processes used for paint adhesion and corrosion resistance and improves the durability of any existing conversion treatments, such as Chromium III (CrIII), Zinc Phosphate (ZnPh) or Iron Phosphate (FePh). Addibond™ also significantly boosts the performance of conversion treatments when used in a Titanium Zirconium (TiZr).

Addibond™ applications

The unique technologies used in Addibond™ bring significant performance improvements to a wide range of applications:

Adhesive Bonding: 

  • For Automotive (body in white, battery casing)
  • For Electronic (battery)
  • For Aluminium/Plastic (low-energy surface) bonding

Paint Adhesion and Corrosion Resistance: 

  • For boosting Chromium III, CrIII/Zirconium or Zr-based conversion or passivation formulations
  • When used in post-treatment steps (as in sealing formulations or in the final rinse), for Zinc Phosphate conversion treatment, for example.  

 

Addibond™ range benefits

To sum up, the added-value of Addibond™ are:

Potential shorten processing time: 

  • Allows the cleaning and etching steps to be combined
  • Addibond™ can be used without any modification of existing processes when used in the final rinse step 

Improvement of the cost in use:

  • Usable at low dosages (e.g., 100ppm active for Aluminium)
  • Better bath stability due to its lower water sensitivity (when compared to classical benchmarks)

Improve the performances of the conversion treatment and process durability:

  • Better paint adhesion (provides indirect anti-corrosion properties)
  • Increased process durability