کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
11016297 | 1777903 | 2019 | 49 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Life, dislocation evolution, and fracture mechanism of a 41Fe-25.5Ni-23.5Cr alloy during low cycle fatigue at 700â¯Â°C
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
سایر رشته های مهندسی
مهندسی مکانیک
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The low-cycle fatigue behavior, dislocation evolution, and fracture mechanism of a 41Fe-25.5Ni-23.5Cr alloy, Sanicro 25, were investigated under various total strain amplitudes of 0.3%, 0.35%, 0.4%, and 0.5% at 700â¯Â°C. According to strain-controlled fatigue tests, this alloy exhibited a cyclic hardening behavior. The back stress and friction stress increased with increasing total strain amplitude, which was attributed to the increase in the interactions of the dislocations with precipitates and dislocations. The hysteresis loops showed that the serrated flow was particularly pronounced at the total strain amplitude of 0.5%. Furthermore, the plastic strain amplitude and the hysteresis loop area increased as the total strain amplitude increased. The modified relationship of fatigue life and plastic strain amplitude (Nf-Îεp/2) was established based on the energy-based prediction model of fatigue life, which was influenced by the parameters cyclic strain hardening exponent nâ² and cyclic strength coefficient Kâ². Nf increased with the increase in nâ², whereas decreased with the increase in Kâ² at the same Îεp/2. TEM observations showed that straight dislocation lines were transformed into zigzag dislocation lines with increasing total strain amplitude. The relationship between the deformation and misorientation was analysed, and the fraction of grains with relatively high Taylor factor increased with increasing total strain amplitude. Finally, the microstructures of the fracture surface and the fracture frontier were studied to understand the fracture mechanism. The intergranular cavities, dimples and tear ridges were observed from fracture surface. The propagation path of microcrack at the fracture frontier was also shown, which indicated a mixture of transgranular and intergranular fracture modes.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Fatigue - Volume 119, February 2019, Pages 20-33
Journal: International Journal of Fatigue - Volume 119, February 2019, Pages 20-33
نویسندگان
Haizhou Li, Hongyang Jing, Lianyong Xu, Lei Zhao, Yongdian Han, Zhengxin Tang, Bo Xiao, Yu Zhang,