Exploring the Ti-5553 phase transformations utilizing in-situ high-temperature laser-scanning confocal microscopy

Autor(es)

Campo, Kaio Niitsu ^[1] ; Fanton, Leonardo ^[1] ; de Mello, Mariana Gerardi ^[1] ; Moon, Suk-Chun ^[2] ; Dippenaar, Rian ^[2] ; Caram, Rubens ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Sch Mech Engn, Campinas, SP - Brazil

^[2] Univ Wollongong, Sch Mech Mat Mechatron & Biomed Engn, Wollongong, NSW - Australia

• Tipo de documento: Artigo Científico
• Fonte: MATERIALS CHARACTERIZATION; v. 159, JAN 2020.
• Citações Web of Science: 0

Resumo

Recently, the beta metastable Ti -5553 alloy has attracted significant interest owing to the possibility of achieving excellent mechanical properties. In this study, for the first time, the Ti-5553 phase transformations were investigated using high-temperature laser-scanning confocal microscopy (HT-LSCM). During the continuous heating of an aged sample, the a phase dissolution was not clearly visible owing to the remaining grooves of former grain and interphase boundaries. However, the continuous cooling experiments (from the beta field) showed that the alpha phase precipitation started preferentially at grain boundaries. With the increase in cooling rate, the alpha precipitates became more refined and the supercooling necessary to promote allotriomorphic precipitation increased. At a cooling rate of 100 degrees C min(-1), no a phase was observed in the analyzed field of view. A higher oxygen content was suggested to contribute to the microstructural differences between the free surface and bulk. The volume fraction of the alpha phase was lower than that obtained on the original surface at cooling rates of 5, 25, and 50 degrees C min(-1), while only minor differences were observed at cooling rates of 100 and 250 degrees C min(-1). The a phase precipitation was analyzed in detail. The HT-LSCM technique can be a useful method for the analyses of solid-state phase transformations in Ti alloys. (AU)

• Processo FAPESP: 18/08184-7 - Observações in situ de transição de fase sólido-sólido em ligas de titânio
• Beneficiário: Rubens Caram Junior
• Modalidade de apoio: Auxílio à Pesquisa - Regular