Thermal decomposition of mechanically alloyed nanocrystalline fcc Fe60Cu40

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	Thermal decomposition of mechanically alloyed nanocrystalline fcc Fe60Cu40
	J. Y. Huang; Y. D. Yu; Y. K. Wu; H. Q. Ye; Z. F. Dong
	1996
发表期刊	Journal of Materials Research
ISSN	0884-2914
卷号	11 期号:11 页码:2717-2724
摘要	A ferromagnetic and supersaturated fee Fe60Cu40 solid solution was prepared by mechanical alloying (MA). The phase transformations of the as-milled Fe60Cu40 powder upon heating to 1400 degrees C and subsequently cooling to room temperature were characterized by differential thermal analysis (DTA) and thermal magnetic measurement. The fee Fe60Cu40 solid solution decomposes into alpha-Fe(Cu) + gamma-Fe(Cu) + Cu(Fe) upon heating from 300 to 460 degrees C, and on further heating, alpha-Fe(Cu) transforms to gamma-Fe(Cu) at 640 --> 760 degrees C; during cooling, the reverse transformation occurs from 800 --> 640 degrees C (obtained from thermomagnetic measurement) or from 700 --> 622 degrees C (obtained from DTA). The gamma reversible arrow alpha transformation in mechanically alloyed Fe60Cu40 nanocrystalline occurs in a wide temperature range; the transformation temperature is higher than that of the martensite transformation in as-cast Fe-Cu alloys, but is much lower than that of the allotropic transformation of pure Fe. These differences may be caused by the different fabrication process, the nonequilibrium microstructure of MA, as well as the inhomogeneous grain size in alpha-Fe(Cu). High resolution transmission electron microscope (HRTEM) observations carried out in the specimen after the DTA run show that N-W or K-S orientation relationships exist between alpha-Fe(Cu) and Cu(Fe), which also represent the orientation relationship between alpha-Fe(Cu) and gamma-Fe(Cu) due to excellent coherency between gamma-Fe(Cu) and Cu(Fe). The grain size of the alpha-Fe(Cu) is inhomogeneous and varies from 50-600 mm. Energy dispersive x-ray spectroscopy (EDXS) result shows that the Cu content in these alpha-Fe(Cu) grains reaches as high as 9.5 at. % even after DTA heating to 1400 degrees C, which is even higher than the maximum solubility of Cu in gamma-Fe above 1094 degrees C. This may be caused by the small grain size of alpha-Fe(Cu).
部门归属	acad sinica,inst met res,natl lab rsa,shenyang 110015,peoples r china.;huang, jy (reprint author), acad sinica,inst met res,atom imaging solids lab,shenyang 110015,peoples r china
关键词	Fe-cu Immiscible Elements Stability Behavior
URL	查看原文
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/38304
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	J. Y. Huang,Y. D. Yu,Y. K. Wu,et al. Thermal decomposition of mechanically alloyed nanocrystalline fcc Fe60Cu40[J]. Journal of Materials Research,1996,11(11):2717-2724.
APA	J. Y. Huang,Y. D. Yu,Y. K. Wu,H. Q. Ye,&Z. F. Dong.(1996).Thermal decomposition of mechanically alloyed nanocrystalline fcc Fe60Cu40.Journal of Materials Research,11(11),2717-2724.
MLA	J. Y. Huang,et al."Thermal decomposition of mechanically alloyed nanocrystalline fcc Fe60Cu40".Journal of Materials Research 11.11(1996):2717-2724.