Microstructure evolution and mechanical property of nanocrystalline Ni-20Fe alloy during cold rolling
- 作者：H.T. Ni ; X.Y. Zhang ; kehen888@163.com
- 关键词：Nanostructured materials ; Microstructure ; Mechanical properties ; X-ray diffraction
- 刊名：Journal of Alloys and Compounds
- 出版年：2012
- 期刊代码：45_09258388
- 类别：ms
- 出版时间：25 May, 2012
- 卷：524
- 期：Complete
- 页码：73-76
- 文件大小：641 K
摘要
We report the microstructure evolution and mechanical property during room-temperature rolling of nanocrystalline Ni-20Fe alloys. The results show that massive dislocations and deformation twins in the deformed samples. Quantitative x-ray analysis reveals deformation induced grain rotation and grain growth. The dislocation density increases firstly and then tend to saturation after an equivalent strain (蓻VM) of 鈭?.10 during the deformation. Correspondingly, the hardness increases when the 蓻VM increases from 0 to 鈭?.10, in spite of the increase in grain size. However, once the 蓻VM exceeds 0.10, the hardness starts to decrease. It is suggested that the role of crystal defect as well as grain size should be considered to better understand the mechanical property of nanocrystalline Ni-20Fe alloy. At small strains (蓻VM < 0.10), the increase in hardness is a direct consequence of the high-density crystal defects; while at large strains (蓻VM > 0.10), since the crystal defects are saturated, the hardness decreases with further increase in grain size.