Tamires Rocha Souza 1, Acelino Cardoso de Sá 2, Fernanda dos Santos Franco 1, Priscila Fernanda Pereira Barbosa 1, Rômulo Davi Albuquerque Andrade 3, Fabíola Medeiros da Costa 1, Kamilla Alves Carvalho 1, Denys Ribeiro de Oliveira 1, Loanda Raquel Cumba 4, Leonardo Lataro Paim 5, Eduardo Guimarães Vieira 6, Devaney Ribeiro do Carmo 1, *ġSão Paulo State University (Unesp), School of Engineering, Department of Physics and Chemistry, Campus of Ilha Solteira, Brazil.ĢSão Carlos Institute of Physics, University of São Paulo, CP 369, São Carlos, Brazil.ģInstitute of Education, Science and Technology of Goiás, Campus of Valparaíso, Brazil.ĤSchool of Chemical Sciences, Dublin City University, Dublin 9, Ireland.ĥSão Paulo State University (Unesp), Energy Engineering, Campus of Rosana, BrazilĦDepartment of Fundamental Chemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil *E-mail: Corrosion of Ti6Al4V Coupled With NiCr as a Dental Implant Alloy in Fluoride Solutions Horácio de Macedo 2030 Bloco I Cidade Universitária, Rio de Janeiro, Brazil. Federal University of Rio de Janeiro, Department of Materials and Metallurgical Engineering (COPPE/UFRJ), Av. Athos da Silveira Ramos, 149 - Centro de Tecnologia, Bloco A Sala 517 Cidade Universitária, Rio de Janeiro, Brazil.ĥMetallurgical Engineering, Coordinator, LabCorr (Corrosion Laboratory), Professor, Department of Materials and Metallurgical Engineering (COPPE/UFRJ). Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos, 149 - Centro de Tecnologia, Bloco A, Sala 517 Cidade Universitária, Rio de Janeiro, Brazil.ĤChemistry, Coordinator, LaDA (Analytical Development Laboratory), Professor, Department of Analytical Chemistry (UFRJ). Student, LaDA (Analytical Development Laboratory), Department of Analytical Chemistry (PGQu/UFRJ). Horácio de Macedo 2030 Bloco I Cidade Universitária, Rio de Janeiro, Brazil.ģChemistry, DSc. Horácio de Macedo 2030 Bloco I Cidade Universitária, Rio de Janeiro, Brazil.ĢChemical, Research Staff, LabCorr (Corrosion Laboratory), Department of Materials and Metallurgical Engineering (COPPE/UFRJ). Student, LabCorr (Corrosion Laboratory), Department of Materials and Metallurgical Engineering (COPPE/UFRJ). Silica is a major constituent of the crust occurring as the silicate minerals, which are the most common minerals of igneous and metamorphic rocks.Camila Dias dos Reis Barros 1, Janaina Cardozo Rocha 2, Bernardo Ferreira Braz 3, Ricardo Erthal Santelli 4 and José Antônio da Cunha Ponciano Gomes 5ġDentistry, D Sc.
It occurs principally in combination as oxides, of which the chief are silicon, aluminum, iron, calcium, magnesium, potassium and sodium oxides. The common rock constituents of the Earth's crust are nearly all oxides chlorine, sulfur and fluorine are the only important exceptions to this and their total amount in any rock is usually much less than 1%.Ĭlarke calculated that a little more than 47% of the Earth's crust consists of oxygen. The crust and underlying relatively rigid mantle make up the lithosphere.īecause of convection in the underlying plastic, although non-molten, upper mantle and asthenosphere, the lithosphere is broken into tectonic plates that move. The temperature of the crust increases with depth, reaching values typically in the range from about 500 ☌ (900 ☏) to 1,000 ☌ (1,800 ☏) at the boundary with the underlying mantle. Some of these less dense rocks, such as granite, are common in the continental crust but rare to absent in the oceanic crust. The continental crust is typically from 30 km (20 mi) to 50 km (30 mi) thick, and it is mostly composed of less dense rocks than is the oceanic crust. The oceanic crust is 5 km (3 mi) to 10 km (6 mi) thick and is composed primarily of basalt, diabase, and gabbro.
The oceanic crust of the Earth is different from its continental crust. The boundary between the crust and mantle is conventionally placed at the Mohorovicic discontinuity, a boundary defined by a contrast in seismic velocity.Įarth's crust occupies less than 1% of Earth's volume. The upper part of the mantle is composed mostly of peridotite, a rock denser than rocks common in the overlying crust. The crust of the Earth is composed of a great variety of igneous, metamorphic, and sedimentary rocks.