نوع مقاله : مقاله پژوهشی
نویسندگان
1 دانشجوی مقطع کارشناسی ارشد/ دانشگاه صنعتی مالک اشتر/ مجتمع مواد و فناوری‌های ساخت/ تهران/ ایران
2 دانشیار/ مجتمع مواد و فناوری‌های ساخت/ دانشگاه صنعتی مالک اشتر/ تهران/ ایران
3 مربی/دانشگاه صنعتی مالک اشتر/ مجتمع مواد و فناوری‌های ساخت/ تهران/ ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
In This study, in order to investigate the flow curves and elongation of Ti-3Al-8Mo-7V-3Cr titanium alloy (Ti-3873), the hot tensile tests were performed at a constant strain rate of 0.1 s-1 and the temperature range of 650-850℃. To establish the relationship between microstructural evolution and flow behavior for determining restoration mechanism, the microstructure of the specimen was examined by optical microscopy (OM) and scanning electron microscopy (SEM) after and before hot deformation. The results showed that the tensile behavior of Ti-3873 alloy in the dual-phases region (650-700℃), due to the nature of α-β phases and crystallographic structure of them, was different from single β phase (750-850℃). The elongation increased from 33% to 54%, due to the transformation of α to β and then gradually eliminating the α phase, at the temperatures of 650-750℃. The maximum ductility obtained at 850℃ with a 71% increase in the length. Microstructural studies showed the elongated and serrated boundaries confirmed the occurrence of dynamic recovery. Recrystallized grains were observed at 850℃. therefore, it can be demonstrated that the dominant mechanism for the Ti-3873 alloy during hot tention is dynamic recovery and partial dynamic recrystallization. according to the hot tention results, the appropriate range of temperature for hot deformation of the Ti-3873 alloy in this study is 800-850℃.
کلیدواژه‌ها [English]
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