Innovative coating to prevent white film defects

For many years foundrymen have been struggling with the casting defect “white film”, which appears on the casting surfaces of thick-walled castings made of nodular graphite cast iron. This is a pockmark-like, rough area on the casting surface, which is covered with a white film. The film is removed by sandblasting the castings; however the irregular surface remains and often leads to graphite degeneration.   

The Hüttenes-Albertus team has investigated in great detail the cause of this problem. Working in close collaboration with selected partners from the foundry industry, a group of R&D chemists and product managers examined through research the causes and conducted field trials. An innovative impregnating coating was developed by closely analysing the causes for the emergence of the film and carrying out individual process steps to overcome the defect. 

The HA team will present this and other developments and solutions in detail at the GIFA 2015.


[1] 2. Edition: Guß- und Gefügefehler – Stephan Hasse: Berlin - Schiele & Schön, 2003

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  • The term coating was originally current in the product engineering sector. "Coating" describes the process of making the surface of a part smooth.

In foundry engineering, coatings are finishing materials applied to moulds and cores to obtain a smooth mould surface. Finely milled refractory materials and highly fireproof substances are used as base materials for such coatings. The coating layer insulates the underlying material and protects it from the thermal stress caused by the molten metal.

Initially coatings of very simple composition, these materials have developed into complex compounds containing different ingredients developed for most different applications.


Coatings for all applications

As one of the world’s largest suppliers of foundry chemical products, Hüttenes-Albertus offers coatings for every application. At present, over 100 different products are on the production range, and their properties are tailored to our customers’ needs.

As moulding sand binders are in a process of constant development, coatings must follow and adapt to the changes. This is made possible by new raw materials which are tried and tested and adapted in an ongoing process of development.


Surface optimization with latest technology

  • uniform layer design,
  • stability of processing,
  • controlled rheological properties,
  • controlled gas permeability,
  • clean castings.

Optimised Coating System for Robot-Supported Core Production

Together with its customers, Hüttenes Albertus has already optimised moulding materials and binder systems for robot-supported core production. With Arkopal 7899 Q, HA now also offers a coating specifically optimised for automated core package processing. 

Please read our full product article.


Please contact our product management team for detailed information on our coatings:

Tel:     +49 211 5087 -213 / -214 

Fax:    +49 211 50 77 57