1. Structure evolution of Y2O3 and consequent effects on mechanical properties of W–Y2O3 alloy prepared by ball milling and SPS.
- Author
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Wang, Man, Sun, Honghong, Pang, Baolin, Xi, Xiaoli, and Nie, Zuoren
- Subjects
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TUNGSTEN alloys , *BALL mills , *MECHANICAL alloying , *TRANSMISSION electron microscopes , *ALLOYS , *SCANNING electron microscopes , *GRAIN refinement - Abstract
Aggregation of Y 2 O 3 particles with relatively large size along grain boundaries is a main limiting factor for performance improvement in W–Y 2 O 3 alloys. In order to tailor the distribution and achieve size refinement of Y 2 O 3 dispersoids, W–Y 2 O 3 alloy was prepared using ball milling with extended milling time and subsequent spark plasma sintering (SPS) in this study. Microstructure evolution of Y 2 O 3 during the preparation process was characterized in detail using X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM). Mechanical properties of SPSed alloy were evaluated in terms of microhardness, three-point bending and compression tests. Structure transformation of Y 2 O 3 from BCC to FCC during the process of ball milling and subsequent sintering was first identified in W–Y 2 O 3 alloy in this study. Compared with the raw micron sized Y 2 O 3 powders, the transformed Y 2 O 3 dispersoids experienced significant size refinement. Around 76% of the nanosized Y 2 O 3 dispersoids were distributed inside grain interior, and they exhibited semi-coherent relationship with tungsten matrix. These microstructural characteristics contributed to the high compressive strength of 1804.2 MPa and microhardness of 625.7 HV in the SPSed W–Y 2 O 3 alloy. • W–Y 2 O 3 alloy were prepared by extended ball milling and SPS. • Structure transformation of Y 2 O 3 from BCC to FCC was identified in W–Y 2 O 3 alloy. • Y 2 O 3 also experienced size refinement and 76% of them were inside grain interior. • The nanosized Y 2 O 3 exhibited semi-coherent relationship with tungsten matrix. • Y 2 O 3 dispersoids contributed to improved strength mainly through grain refinement. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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