Effect of Cobalt Doping and Milling Time on Microstructure and Vickers Microhardness of the Spark Plasma Sintered (67-x)Ti-xCo-22Si-11B (x=2 and 6 at-%) Alloys

Autor(es)

Ferreira, Nelson Damasio ^[1] ; Leal Neto, Ricardo Mendes ^[2] ; Filgueira, Marcello ^[3] ; Rodrigues Pais Alves, Manuel Fellipe ^[4] ; dos Santos, Claudinei ^[5] ; Ramos, Alfeu Saraiva ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Alfenas, Inst Ciencia & Tecnol, Rodovia Jose Aurelio Vilela 11999, BR-37715400 Pocos De Caldas, MG - Brazil

^[2] Inst Pesquisas Energet & Nucl, Av Prof Lineu Prestes, 2242, Cidade Univ, BR-05508000 Sao Paulo, SP - Brazil

^[3] Univ Estadual Norte Fluminense, Ave Alberto Lamengo 200, Parque California, BR-28013602 Campos Dos Goytacazes, RJ - Brazil

^[4] Univ Sao Paulo, Escola Engn Lorena, Gleba AI-6, BR-12602810 Lorena, SP - Brazil

^[5] Univ Estado Rio de Janeiro, Fac Tecnol Resende, Rodovia Presidente Dutra Km 298, BR-27537000 Resende, RJ - Brazil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 23, n. 6 2020.
• Citações Web of Science: 0

Resumo

Ti-6Al-4V and TiAl-based alloys are widely used for fabricating the implantable orthopedic devices and automotive components, respectively. Ti6Si2B-based alloys are attractive for use in orthopedic components because their higher hardness, superior biocompatibility and corrosion resistance in simulated body fluid than Ti and Ti-6Al-4V alloy. Limited information on Ti6Si2B stability in Co-dopped 67Ti-22Si-11B alloys are available in literature. This work presents the effect of cobalt doping and milling time on microstructure and Vickers microhardness of 65Ti-2Co-22Si-11B and 61Ti-6Co-22Si-11B (at-%) alloys produced by spark plasma sintering at 1100 degrees C for 12min using 20MPa. Samples were characterized by X ray diffraction, scanning electron microscopy, energy dispersive spectrometry, laser particle size analysis, and Vickers microhardness. Sintered alloys with 2 and 6at-%Co indicated the major presence of Ti6Si2B and Ti5Si3 dissolving up to 2.7 and 4.2 at-%Co, respectively, besides the minor precipitates of CoTi2 (4.4-16.7at-%Si) and CoTi (4.6-4.7at-%Si). Vickers microhardness of the sintered 65Ti-2Co-22Si-11B and 61Ti-6Co-22Si-11B alloys were in the range of 950-1050 and 1050-1150HV, respectively. Although the increase from 2 to 6at-%Co has reduced the Ti6Si2B stability, the Co-rich phases increased their hardness values up to 1150HV (11.3GPa), which are superior than those of commercial Ti alloys used for joint orthopedic components and automotive rotating parts. (AU)

• Processo FAPESP: 01/03961-4 - Sintese por combustao mecanicamente ativada do trialumineto de niobio , nbal3.
• Beneficiário: Ricardo Mendes Leal Neto
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 07/50018-2 - Construcao e operacao de um sistema para o estudo da hidretacao desidretacao de materiais armazenadores de hidrogenio.
• Beneficiário: Ricardo Mendes Leal Neto
• Modalidade de apoio: Auxílio à Pesquisa - Regular