Formation of abnormal structure in ZTA15 titanium alloy casting and its impact mechanism on tensile behavior
Partial block-dropping phenomenon was existed during the precision process of TA15 titanium alloy casting. In view of multiple means of microscopic physical characterization analysis such as OM/SEM/EDS/XRD and by considering the tensile performance results, the microstructure and mechanical properti...
Main Authors: | , , |
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Format: | Article |
Language: | zho |
Published: |
Journal of Aeronautical Materials
2020-08-01
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Series: | Journal of Aeronautical Materials |
Subjects: | |
Online Access: | http://jam.biam.ac.cn/article/doi/10.11868/j.issn.1005-5053.2020.000060 |
Summary: | Partial block-dropping phenomenon was existed during the precision process of TA15 titanium alloy casting. In view of multiple means of microscopic physical characterization analysis such as OM/SEM/EDS/XRD and by considering the tensile performance results, the microstructure and mechanical properties between block-dropping area and the regular areahad been investigated. This article focused on the impact mechanism on tensile behavior that generated from the abnormal structure of block-dropping area. The results reveal that both the block-dropping area and the regular area show bi-modal microstructure, whereas the β phase concentration of the block-dropping area is far beyond the regular area and emerges as β spot. Microanalysis shows that the segregation of Fe is the major factor causing the abnormal structure and β spot, as well as the sharp plasticity decreases of alloy. The segregated Fe alters the microstructure and properties of the alloy, mainly because the saturation of Fe in α-Ti is only 0.1%, which leads to the formation of brittle TiFe eutectic phase. The increase of strength reduces the plasticity of the alloy casting, and further lead to the block-dropping during the process. |
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ISSN: | 1005-5053 1005-5053 |