Papers by Keyword: Fe-Cu Alloy

Abstract: In the present work, Fe-Cu based alloys with different compositions have been obtained by using Powder metallurgy (PM). These alloys were created with the purpose of increasing mechanical properties of the parts. Nevertheless, little have been published, once this is a matter of industrial interest. In this work, samples of Fe_100-x Cu_x (x=0.40, 0.55, 0.70, 0.85 and 1) alloys were processed by cold pressing at 10 MPa, followed by sintering at 1250 C°. Structures formed during sintering were studied by EDS. Microstructural aspects were observed by MEB. Densification and microhardness tests were also performed.

Abstract: The precipitation of copper during aging at 600oC in high-purity Fe-Cu alloy was examined by means of transmission electron microscopy (TEM).Nano-scale copper-rich clusters with a B2-like structure were observed during heat treatment. These micro structural features play an important role in precipitation strengthening. In addition, the precipitation process has been analyzed in terms of the evolution of microstructure by a Monte Carlo method. A description of the coherent precipitation of copper in iron, based on a vacancy diffusion mechanism, thermally activated jump frequencies and cohesive energy is discussed in order to deal with simultaneous precipitation of metastable and stable phases in Cu-containing steel during aging. This analysis gives an estimation of the precipitation dynamics, as well as the evolution of Cu precipitates across a wide range of temperatures.

Abstract: Aging of Fe-Cu alloys or steels containing copper may result in the formation of the dispersion of nanometric precipitates in the matrix and, thus, causes a great increase in the strength of the alloys. A model is developed describing the aging process of Fe-Cu alloys. The model is first satisfactorily verified by comparing with the reported experimental results, and then applied to calculate the microstructure evolution during aging a Cu-Fe alloy. The numerical results demonstrate that the nucleation of the precipitates occurs after a period of incubation. Since that time on the microstructure evolution is the result of the concurrent action of nucleation, growth/shrinkage and structural transformation of the precipitates. In the late stage of aging almost all the precipitates are of 9R structure. The mean particle radius varies linearly with the cube root of time

Abstract: New type Fe-Cu alloy is used in the bar of induction motor with compound cage rotor(IMCCR). In this paper, the preparation of three kinds of Fe-Cu alloy is introduced. The influence of its microstructures, hardness and impact toughness is studied by using metalloscope and scanning electron microscope. Meanwhile, physical propertie such as resistivity, and B-H curve is tested by using magnetic testing device and bridge circuit. The influence of carbon content changing on microstructure and performance of Fe-Cu alloy is analysised, which has positive significance to the new type material using in motor.

Abstract: This paper describes a computer simulation of thermal ageing process in Fe-Cu alloy. In order to perform accurate numerical simulation, firstly, we make numerical models of the diffusion and dissociation of Cu and Cu-vacancy clusters. This modeling was performed with kinetic lattice Monte Carlo method, which allows us to perform long-time simulation of vacancy diffusion in Fe-Cu dilute alloy. The model is input to the kinetic Monte Carlo method, and then, we performed the kinetic Monte Carlo simulation of the thermal ageing in the Fe-Cu alloy. The results of the KMC simulations tell us that the our new models describes well the rate and kinetics of the diffusion and dissociation of Cu and Cu-vacancy clusters, and works well in the kinetic Monte Carlo simulations. Finally, we discussed the further application of these numerical models.