Precipitation behavior of α phase during aging treatment in a β-quenched Ti-7333

Journal Article · Fri Jun 15 04:00:00 EDT 2018 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2018.04.008· OSTI ID:22832980

Dong, Ruifeng ^[1]; Li, Jinshan; Kou, Hongchao ^[1]; Fan, Jiangkun; Tang, Bin; Sun, Miao ^[1]

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1. State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072 (China)

Highlights: • The precipitation behaviors of α precipitate are investigated in the hot-rolled Ti-7333. • The formation of the V-shaped α configuration is closely related to the variant selection of α phase. • The angle between the closely packed direction of α{sub GB} and GB plane plays a key role on the precipitation of α{sub GB}. - Abstract: In this work, the precipitation behavior of α phase during the isothermal aging treatment was investigated in the β-quenched Ti-7333. The results indicate that dislocations contribute to the precipitation of α phase with a dot-like morphology at the beginning of aging treatment, and these dot-like α precipitates holding the same Burgers orientation relationship (BOR) with respect to the β matrix coalesce into the platelet morphology. The platelet-like α precipitates that orientate to different growth directions combine with each other to form the V-shaped configuration. And the formation of this configuration is closely related with the variant selection (VS) of α phase, which is resulted from the perfect accommodation of transformation strain within the β matrix. Meanwhile, it is found that low-angle grain boundaries (LAGBs) and high-angle grain boundaries (HAGBs) can be decorated by α phase during the aging treatment, and its precipitation degree significantly depends on the angle between the closely packed direction of αGB and the GB plane. The volume fraction of α phase increases with increasing aging time, and this increasing volume fraction eventually results in the increase in micro-hardness of the alloy.

• OSTI ID: 22832980
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 140; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
AGING
DISLOCATIONS
GRAIN BOUNDARIES
HARDNESS
HEAT TREATMENTS
PRECIPITATION
TITANIUM ALLOYS