کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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797949 | 1466740 | 2016 | 7 صفحه PDF | دانلود رایگان |
Ti-6Al-4V specimens with different thermal histories were obtained by controlling their solidification and cooling through an automatic temperature-controlled induction melting apparatus. The final microstructure of Ti-6Al-4V was determined by both isothermal holding temperature and time during solidification, especially near the β transus temperature. A unique bimodal microstructure consisting of high aspect ratio α particles and small colonies with fine secondary lamellar α appeared in specimens isothermally held from 950 °C to 970 °C. Water quenching was conducted after isothermal holding treatment for comparison. X-ray diffraction, transmission electron microscopy, and electron probe microanalysis were used to explore the evolution mechanism of the unique bimodal microstructure. Primary α breakdown occurred during isothermal holding treatment because of Ostwald ripening and boundary splitting mechanisms. The formation of small colonies with fine secondary lamellar α was also discussed.
Journal: Journal of Materials Processing Technology - Volume 227, January 2016, Pages 281–287