Carlos Eduardo Gomes Ribeiro

Production of Synthetic Ornamental Marble as a Marble Waste Added Polyester Composite

The worldwide demand for ornamental stones in building construction is motivating the use of their wastes, generated during fabrication, to produce synthetic stones. This work has as its objective to investigate the production of a synthetic ornamental marble (SOM) under vacuum and vibro-compression processing of a polyester matrix composite with addition of marble waste as a filler. Rectangular SOM composite plates were subjected to compression and flexural mechanical tests. Samples were analyzed to obtain the density, water absorption, and microstructure. The SOM composites presented properties within the expected range of an artificial stone, which indicates that the applied process is suitable for production of this type of material.

Fabrication of Artificial Stone from Marble Residue by Resin Transfer Molding

Artificial stones have recently been worldwide commercialized but are still not produced in Brazil. This has motivated efforts for the local fabrication of a similar stone. Thus, an artificial ornamental stone (AOS) was fabricated by means of a resin transfer molding (RTM) process. Marble residues were placed inside a hermetic mold under vacuum. A still fluid polyester resin, already mixed with a catalyst and a thinner, was injected into the mold. After curing, the density and water absorption of the AOS were evaluated. The material was also subjected to both compression and bend mechanical tests. The AOS microstructure was analyzed by scanning electron microscopy, which was then related to the obtained physical and mechanical properties.

Development of Epoxy Matrix Artificial Stone Incorporated with Sintering Residue from Steelmaking Industry

The present work is part of an innovation research project aiming to develop artificial stone from industrial wastes. In principle, the project goal is to fabricate artificial stones with improved characteristics to be used as plates for housing and road construction. In this work, the specific industrial residue was an electrostatically precipitated powder obtained from the initial sintering stage of an integrated steelmaking plant. Plates were produce by vacuum vibro-compression of epoxy resin mixed with 80 and 85 wt% of this specific residue. After curing, the plates were characterized for physical parameters and mechanical properties. The microstructural aspect of the finishing surface was analyzed for both novel artificial stones by scanning electron microscopy. The results indicated that the 80% residue incorporated artificial stone is superior to the 85% residue incorporated and markedly stronger than a commercial artificial stone, incorporated with granite residue, with comparable density and water absorption. These characteristics favor the technical substitution of the presently investigated artificial for the commercial stone. In particular, based on wear tests, the residue incorporated artificial stone would be restricted to application as pavement in medium traffic roads.

Influence of Compaction Pressure and Particle Content on Thermal and Mechanical Behavior of Artificial Marbles with Marble Waste and Unsaturated Polyester

Compact artificial stones are widely used in buildings around the world, and the expected demand to the next years is increasing. In this study, stone fragments from marble processing are recycled as raw materials for produce compact artificial stones using compaction in a vacuum environment (100 mm Hg). Crushed marble waste (80 and 85%wt) are mixed with unsaturated polyester resin as binder. Materials were processed under compaction pressures of 1 and 10 MPa, for 20 minutes at 90 °C. Artificial marble with flexural ultimate strength of 25 MPa, water absorption below 0.2% and homogeneous particles distribution were obtained to materials produced with 80%wt of marble particles. To artificial marbles with 85%wt of particles, lower flexural ultimate strength and higher water absorption were observed (18 MPa and 0.4% respectively). In addition, the greater compaction pressure used improves slightly values obtained in 3 points bending test. Furthermore, tangent delta peaks at 115 °C were observed to evaluated artificial marbles.

Chemical Resistance of Ornamental Compound Stone Produced with Marble Waste and Unsaturated Polyester

Ornamental compound stone are produced by industry for decades, however, few published studies describe these materials. Brazil has many deposits of stone wastes and a big potential to produce these materials. This work aims to evaluate the chemical resistance of ornamental compound stones produced with marble waste and unsaturated polyester. An adaptation of Annex H of ABNT NBR 13818:97 standard, with reagents commonly used in household products, was used. The results were compared with those obtained for natural stone used in composite production.