This paper deals with the issue of using moulding sands with a new two-component binder: furfuryl-resole resin – PCL polycaprolactone for the production of ductile iron heavy castings. The previous laboratory studies showed the possibility of using biodegradable materials as binders or parts of binders’ compositions for foundry moulding and core sands. The research proved that addition of new biodegradable PCL in the amount of 5% to the furfuryl-resole resin does not cause significant changes in moulding sand’s properties. The article presents research related to the production of ductile iron castings with the use of moulds with a modified composition, i.e. sands with furfuryl resole resin with and without PCL. Mechanical properties and microstructure of the casting surface layer at the metal/ mould interface are presented. The obtained test results indicate that the use of a biodegradable additive for making foundry moulds from moulding sand with a two-component binder does not deteriorate the properties of ductile iron castings.

Casting industry has been enriched with the processes of mechanization and automation in production. They offer both better working standards, faster and more accurate production, but also have begun to generate new opportunities for new foundry defects. This work discusses the disadvantages of processes that can occur, to a limited extend, in the technologies associated with mould assembly and during the initial stages of pouring. These defects will be described in detail in the further part of the paper and are mainly related to the quality of foundry cores, therefore the discussion of these issues will mainly concern core moulding sands. Four different types of moulding mixtures were used in the research, representing the most popular chemically bonded moulding sands used in foundry practise. The main focus of this article is the analysis of the influence of the binder type on mechanical and thermal deformation in moulding sands.