Experimental Study of Inorganic Foundry Sand Binders for Mold and Cast Quality

Abstract

The interest in inorganic foundry binders has been rising steadily in recent times due to their favorable environmental characteristics. This paper compares the mold quality and cast quality attained with different inorganic binders. Three different types of sand and five different inorganic binders were used for the mold quality study. Of the inorganic binders, there was liquid sodium silicate used in different hardening methods, a geopolymer binder, and also solid sodium silicate. The mold quality was assessed through bending strength, residual bending strength, tensile strength, and loss on ignition measurement. A total of 12 castings were made using molds of different binders and sand materials. The cast quality was then assessed by tracking changes in dimension and the surface quality of final castings. Inorganic binders performed well in terms of mold strength and very well in terms of loss on ignition but there is room for improvement in the surface quality of the castings attained.

Limitations and advancements of Sodium Silicate inorganic sand binders; A review

“…However, they offer higher shelf life and moisture resistance than the molds binded with liquid silicates. Consequently, we can conclude that due to this variability in the initial binders form, there will be a disparity in the input parameters and hence in the output performance [18,19,20,21,22].…”

Carbonation Curing and Kinetics of Wood-Sodium Silicate Composites

“…Carbonation curing, which is the diffusion of CO 2 into the pores of a matrix, has been used in different studies with common uses in composites made of natural fibers like wood and cement to stabilize and improve the mechanical properties of the materials. − Carbonation products formed during curing can fill the voids and pores of the composites improving densification and increasing the strength and durability of the composites . The ecofriendly choice and use of wood fibers in these composites will help in long-term carbon storage while improving the mechanical properties of the composites .…”

“…The potential of carbonated cured wood-geopolymer (such as SS)-based composites, how they perform mechanically and thermally, will aid in establishing proper optimization processing methods for different applications . In the presence of CO 2 , SS reacts to form silica gel with the subsequent removal of water to form a hardened glass material and a byproduct of sodium carbonate (Na 2 CO 3 ) and silica (SiO 2 ) as seen in chemical eq and stoichiometric eq . The dissolution behavior of Na 2 CO 3 contributes to the carbonation curing of the SS in the composite and facilitates bond formation. , When wood is added and treated with SS, CO 2 enhances the functional groups responsible for adhesion between the fibers and the matrix which can contribute to the existing properties and advantages of high strength, fire resistance, and durability as observed in a previous study …”

Eco-Friendly Inorganic Binders: A Key Alternative for Reducing Harmful Emissions in Molding and Core-Making Technologies

“…For many years, sand casting technology was dominated by sands containing bentonite (green sand) and sands bound with organic binders, in which various forms of resins and hardeners (catalysts) were used as binders. Sands with inorganic binders were much less numerous, represented mainly by molding sands bound with water glass [1][2][3]. The introduction of water glass as a binder in the early years of the 20th century played a very important role in increasing the efficiency of mold and core production [1,4].…”