New Materials in the Production of Moulding and Core Sands

Abstract

The article shows the influence of environment requirements on changes in different foundry moulding sands technologies such as cold box, self-hardening moulding sands and green sands. The aim of the article is to show the possibility of using the biodegradable materials as binders (or parts of binders’ compositions) for foundry moulding and core sands. The authors concentrated on the possibility of preparing new binders consisting of typical synthetic resins - commonly used in foundry practice - and biodegradable materials. According to own research it is presumed that using biodegradable materials as a part of new binders’ compositions may cause not only lower toxicity and better ability to reclaim, but may also accelerate the biodegradation rate of used binders. What’s more, using some kinds of biodegradable materials may improve flexibility of moulding sands with polymeric binder. The conducted research was introductory and took into account bending strength and thermal properties of furan moulding sands with biodegradable material (PCL). The research proved that new biodegradable additive did not decrease the tested properties.

Effect of Sand Wetting on Physically Hardened Moulding Sands Containing a Selected Inorganic Binder. Part 1

“…It results from literature data that water present on surfaceactive crystalline structure of high-silica base [16] can penetrate micropores of sand grains and, moreover, it can create superficial layers: adsorptive and absorptive ones, where water will be bonded with the grain material by hydroxyl groups (OH). Good wettability of base and low viscosity of binder increase probability of creating non-enveloped links [8] between the base and the bonding material, which give the sandmix higher strength in comparison to that containing enveloped links.…”

A Comparative Analysis on Organic and Inorganic Core Binders for a Gravity Diecasting Al Alloy Component

“…1,3,4 The binder system and the curing mechanism, i.e., cold-box or hot-box processes, affect the quality of castings in terms of microstructure and mechanical properties, as well as emission in the workplace environment. Against this scenario, foundries have been seeking alternative solutions for sustainable production processes and better working conditions, 5 also, for example, introducing new formulations of binders suitable for the 3D sand printing systems. 6 Inorganic core binders, based on sodium silicate (water glass), are proving to be an effective solution also for structural components, i.e., for automotive aluminum parts.…”

“…The research to date has addressed the properties of organic and inorganic binder-based cores, considering their mechanical and thermomechanical properties, [8][9][10][11][12][13][14] their environmental compatibility, [15][16][17][18] the employment of new compositions 5,[19][20][21][22][23][24] as well as new production technologies. [25][26][27] Attention has also been paid to the humidity resistance of sodium silicate bonded sands and to the curing of the binder.…”

Decoring Behaviour of Chosen Moulding Materials with Alkali Silicate Based Inorganic Binders

“…The foundation of these hot-curing processes was the fact, that moulding materials with "classic" water glass binder can attain significantly higher strengths by drying when using heated tools [4][5][6]. However, developers of inorganic binder systems significantly improved binder properties, still there is a connection to technological problems compared to resin-bonded sands such as low knockout properties, low ability to reclaim [7] and limited storage of cores [3]. This paper is focused on comparison of decoring behaviour of moulding material with different types of sands and additives.…”