Análise das propriedades mecânicas de areia verde para fundição aglomerada com caulim

Abstract

This work analyzes the compactness, permeability and mechanical resistance of a green foundry sand composed of a mixture of silica, kaolin and water. The materials were characterized by determining the particle size distribution (both base sand and green sand) fineness modulus, fines content, clay content. The moisture content varied in a water / clay ratio from 0.1 to 0.3 for agglomerated sand with 10% kaolin and from 0.09 to 0.43 to one with 11.07%. For each compactness, permeability and green compressive strength test 3 ABNT standard specimens with different sand: clay: water ratio were prepared. As enrichment of the work, the permeable properties of the silica sand used in the tests were evaluated. It can be concluded that kaolin, without additives, from Tijucas do Sul city, presents acceptable mechanical compressive strength for its use in casting, however, the permeability was not satisfactory in any composition. The compactability was acceptable only when moisture caused the sand to swell, and at this point there was also the maximum mechanical resistance to compression.