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)

Nelson Damásio Ferreira ^[1] ; Ricardo Mendes Leal Neto ^[2] ; Marcello Filgueira ^[3] ; Manuel Fellipe Rodrigues Pais Alves ^[4] ; Claudinei dos Santos ^[5] ; Alfeu Saraiva Ramos ^[6]

Afiliação do(s) autor(es)

^[1] Instituto de Ciência e Tecnologia. Universidade Federal de Alfenas - Brasil

^[2] Instituto de Pesquisas Energéticas e Nucleares - Brasil

^[3] Universidade Estadual do Norte Fluminense Darcy Ribeiro - Brasil

^[4] Universidade de São Paulo. Escola de Engenharia de Lorena - Brasil

^[5] Faculdade de Tecnologia de Resende. Universidade do Estado do Rio de Janeiro - Brasil

^[6] Instituto de Ciência e Tecnologia. Universidade Federal de Alfenas - Brasil

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS RESEARCH-IBERO-AMERICAN JOURNAL OF MATERIALS; v. 23, n. 6 2020-12-14.

Resumo

Abstract 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 oC 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