The Debye Temperature of Iron-Manganese Solid Solution Alloys

1963 ◽  
Vol 7 ◽  
pp. 14-21
Author(s):  
Charles P. Gazzara ◽  
Raymond M. Middleton

AbstractValues of the Debye temperature 0 for iron-manganese solid-solution alloys have been determined from X-ray diffracted intensity measurements of powder specimens at ambient temperatures of 310, 239, and 98°K. Corrections to 0 were made with respect to the temperature-dependence of Θ, temperature diffuse scattering, dispersion, volume expansion of the alloy, and the temperature gradient through the specimen. The variation of Θ with temperature has been found to be approximately linear, the value of Θ decreasing 3 % between 98 and SICTK. for a nominal Fe–4%Mn alloy.Increasing the concentration of manganese in an iron-manganese solid-solution alloy decreases Θ in qualitative agreement with Lindemann's equation. The values of Θ for other s olid-solution alloys computed using Lindemann's equation also agree with reported experimental values of Θ. The Debye temperature of a nominal Fe-3%Mn alloy annealed for 2 hr at 300, 600, and 700°C has not been found to maximize at 600°C as has been reported by Il'ina et al. On the contrary, Θ decreases with increasing annealing temperature until, in the range 600 to 700°C, it reaches its true value; and at these temperatures the powder was found to be fully annealed.

2015 ◽  
Vol 29 (31) ◽  
pp. 1550196 ◽  
Author(s):  
Y. M. Sun ◽  
W. Q. Yu ◽  
D. Long ◽  
Y. Zhang ◽  
Z. Hua

[Formula: see text] amorphous alloy was prepared by melt-spinning and annealed at various temperatures. The thermal property, microstructure and magnetic property were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The crystallization process of [Formula: see text] alloy is as follow: Amorphous [Formula: see text] residual amorphous [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] solid solution. Coercivity [Formula: see text] of [Formula: see text] alloy changes complexly, which abruptly deteriorates at 843 K and then softens with increasing annealing temperature [Formula: see text].


2011 ◽  
Vol 5 (4) ◽  
pp. 181-186 ◽  
Author(s):  
Sanjay Kumar ◽  
Nagaiyar Krishnamurthy

Synthesis of V-Ti-Cr solid solution alloy by co-reduction of V2O5, Cr2O3 and TiO2 with aluminium in an open bomb reactor was investigated. The reduction of V2O5 and Cr2O3 was highly exothermic while reduction of TiO2 was not sufficiently exothermic for self-sustaining reaction. A range of composition of V2O5, Cr2O3 and TiO2 mixture was chosen to make overall process sufficiently exothermic to sustain the reaction in a controlled manner. After the co-reduction, V-Ti-Cr-Al solid solution was obtained. As-obtained solid solution was refined by electron beam melting (EB) to remove the aluminium and residual oxygen. EB melted V-Ti-Cr thus obtained contains substantially less amount of aluminium (~0.081%.) Throughout the synthesis process the prepared products were analyzed using scanning electron microscope (SEM), energy dispersive X-ray fluorescence (EDAX), chemical analysis, gravimetric analysis and X-ray diffraction.


2014 ◽  
Vol 936 ◽  
pp. 101-104
Author(s):  
Tanabat Promjun ◽  
Saksit Sukprasong ◽  
Ladapak Chumprasert ◽  
Athipong Ngamjarurojana

Ceramics in the xPb (Zn1/3Nb2/3)O3−(1-x)Pb (Zr1/2Ti1/2)O3 [xPZN–(1-x)PZT] solid solution system are expected to display excellent dielectric, piezoelectric, and ferroelectric properties in compositions close to the morphotropic phase boundary (MPB). The dielectric behavior of ceramics with x = 0.1 − 0.5 has been characterized in order to identify the MPB compositions in this system. Combined with x-ray diffraction analysis, dielectric, piezoelectric and ferroelectric measurements, it was consistently shown that an MPB exists around x = 0.3 in this binary system. When x ≤ 0.2, the tetragonal phase dominates at ambient temperatures. In the range of x ≥ 0.4, the rhombohedral phase dominates.


Author(s):  
A. Christou ◽  
J. V. Foltz ◽  
N. Brown

In general, all BCC transition metals have been observed to twin under appropriate conditions. At the present time various experimental reports of solid solution effects on BCC metals have been made. Indications are that solid solution effects are important in the formation of twins. The formation of twins in metals and alloys may be explained in terms of dislocation mechanisms. It has been suggested that twins are nucleated by the achievement of local stress-concentration of the order of 15 to 45 times the applied stress. Prietner and Leslie have found that twins in BCC metals are nucleated at intersections of (110) and (112) or (112) and (112) type of planes.In this paper, observations are reported of a transmission microscope study of the iron manganese series under conditions in which twins both were and were not formed. High strain rates produced by shock loading provided the appropriate deformation conditions. The workhardening mechanisms of one alloy (Fe - 7.37 wt% Mn) were studied in detail.


Author(s):  
Jordi Marti ◽  
Timothy E. Howson ◽  
David Kratz ◽  
John K. Tien

The previous paper briefly described the fine microstructure of a mechanically alloyed oxide dispersion strengthened nickel-base solid solution. This note examines the fine microstructure of another mechanically alloyed system. This alloy differs from the one described previously in that it is more generously endowed with coherent precipitate γ forming elements A1 and Ti and it contains a higher volume fraction of the finely dispersed Y2O3 oxide. An interesting question to answer in the comparative study of the creep and stress rupture of these two ODS systems is the role of the precipitate γ' in the mechanisms of creep and stress rupture in alloys already containing oxide dispersoids.The nominal chemical composition of this alloy is Ni - 20%Cr - 2.5%Ti - 1.5% A1 - 1.3%Y203 by weight. The system receives a three stage heat treatment-- the first designed to produce a coarse grain structure similar to the solid solution alloy but with a smaller grain aspect ratio of about ten.


Author(s):  
R. M. Anderson

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.


Author(s):  
M.D. Ball ◽  
H. Lagace ◽  
M.C. Thornton

The backscattered electron coefficient η for transmission electron microscope specimens depends on both the atomic number Z and the thickness t. Hence for specimens of known atomic number, the thickness can be determined from backscattered electron coefficient measurements. This work describes a simple and convenient method of estimating the thickness and the corrected composition of areas of uncertain atomic number by combining x-ray microanalysis and backscattered electron intensity measurements.The method is best described in terms of the flow chart shown In Figure 1. Having selected a feature of interest, x-ray microanalysis data is recorded and used to estimate the composition. At this stage thickness corrections for absorption and fluorescence are not performed.


Author(s):  
Z. Horita ◽  
D. J. Smith ◽  
M. Furukawa ◽  
M. Nemoto ◽  
R. Z. Valiev ◽  
...  

It is possible to produce metallic materials with submicrometer-grained (SMG) structures by imposing an intense plastic strain under quasi-hydrostatic pressure. Studies using conventional transmission electron microscopy (CTEM) showed that many grain boundaries in the SMG structures appeared diffuse in nature with poorly defined transition zones between individual grains. The implication of the CTEM observations is that the grain boundaries of the SMG structures are in a high energy state, having non-equilibrium character. It is anticipated that high-resolution electron microscopy (HREM) will serve to reveal a precise nature of the grain boundary structure in SMG materials. A recent study on nanocrystalline Ni and Ni3Al showed lattice distortion and dilatations in the vicinity of the grain boundaries. In this study, HREM observations are undertaken to examine the atomic structure of grain boundaries in an SMG Al-based Al-Mg alloy.An Al-3%Mg solid solution alloy was subjected to torsion straining to produce an equiaxed grain structure with an average grain size of ~0.09 μm.


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