International Journal of Materials Research

Published by De Gruyter

Volume 93 Issue 4

April 2002

Issue of International Journal of Materials Research

Contents
Journal Overview

Publicly Available January 4, 2022

Frontmatter

Page range: 255-255

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Articles/Aufsätze

January 4, 2022

⁵⁹Fe Grain boundary diffusion in nanostructured γ-Fe–Ni

Part I: Radiotracer experiments and Monte-Carlo simulation in the type-A and B kinetic regimes

S. V. Divinski, F. Hisker, Y.-S. Kang, J.-S. Lee, Chr. Herzig

Page range: 256-264

Abstract

For the first time, self-diffusion was systematically investigated in well-compacted nanocrystalline (grain size d ≈ 80 – 100 nm) γ-Fe–40 wt.% Ni material in a wide temperature range (600 –1010 K) in all Harrison-type kinetic regimes. Samples were prepared by sintering the nanocrystalline Fe –Ni powder mixture produced by ball milling of the component oxides after reduction in hydrogen atmosphere. The samples revealed a frequently observed bimodal microstructure consisting of nano-scaled grains and micrometer-scaled agglomerates of the nano-grains. Two different types of short-circuit paths were found to control the diffusionflux in such material. Owing to the applied sensitive radiotracer technique Fe diffusion in both types of interface boundaries could be successfully characterized by combining the evaluation of the experimentally determined 59 Fe diffusion profiles with a Monte-Carlo simulation of grain boundary (GB) diffusion. Part I presents the results obtained at elevated temperatures in the type-B and A regimes. Due to the sample preparation process the GB motion during the diffusion anneal was proven to be negligible. For the first time, it was shown that there exists an intermediate stage between the well-known kinetic regimes B and A if Dvt≃d $\sqrt{{{D}_{\rm v}}t}\simeq d$, where D v is the bulk diffusivity and t is the time. The corresponding concentration profiles could be linearized in the coordinates of ln c¯ $\bar{c}$vs. y3/2(c¯ ${{y}^{3/2}}(\bar{c}$is the layer tracer concentration and y is the penetration depth) and the equation to extract the GB diffusion coefficient from these data was derived. The limits of the new AB-type stage were established. It was demonstrated that the processing of the nonconventional experimental GB diffusion profiles in a nanocrystalline material can be done properly but is more sophisticated than in a coarse-grained material.

January 4, 2022

⁵⁹Fe Grain boundary diffusion in nanostructured γ-Fe–Ni

Part II: Effect of bimodal microstructure on diffusion behavior in type-C kinetic regime

S.V. Divinski, F. Hisker, Y.-S. Kang, J.-S. Lee, Chr. Herzig

Page range: 265-272

Abstract

For the first time, the grain boundary diffusion was investigated in a nanocrystalline material in the whole spectrum of possible kinetic regimes: types-C, B, AB , and A. The microstructure of the nanocrystalline γ-Fe-40 wt.% Ni alloy revealed two different levels of organization: the individual nano-scaled grains build up micrometer-large clusters or agglomerates of the grains. The existence of the two types of internal interfaces in the material – the boundaries between the nano-grains and between the agglomerates of these nanocrystallites (the inter- and intraagglomerate boundaries) – affected notably the C-regime of 59 Fe radio-tracer diffusion and resulted in two-stage diffusion penetration profiles. The careful profile processing according to formal criteria of the given kinetic regimes allowed, for the first time, to elaborate a consistent picture of the diffusion behavior in this nanocrystalline material with a complex bimodal distribution of equilibrium and nonequilibrium internal interfaces in the same material. The absolute values of the measured diffusion coefficients and the Arrhenius parameters of Fe diffusion along the nanocrystalline boundaries in nano-γ-Fe-40 wt.% Ni ( D 0 = 4:2 ⨯ 10 –3 m 2 s –1 , Q = 187 kJ mol –1 ) are very similar to the Fe grain boundary diffusivity in coarse-grained γ-Fe. The activation enthalpy of diffusion along the inter-agglomerate boundaries ( D 0 = 3:4 ⨯ 10 –3 m 2 s –1 , Q = 148 kJ mol –1 ) is notably smaller and the absolute diffusivity is larger by two to three orders of magnitude than the corresponding values of Fe diffusion via the nanoboundaries. The observed features are explained by a quasi-equilibrium structure of the nanocrystalline GBs, related to the grain growth during sample preparation, whereas the residual interagglomerate boundaries remained in nonequilibrium state. The potential contribution of the numerous triple junctions in the nano-material to short-circuit diffusion was investigated in detail and was found to be negligible under the present experimental conditions.

January 4, 2022

Thermodynamic assessment of the Cu–Ti system taking into account the new stable phase CuTi₃

P. Canale, C. Servant

Page range: 273-276

Abstract

The thermodynamic parameters of the new phase CuTi 3 found in the Cu–Ti system were optimised using experimental data. A non-stoichiometric description of that phase was taken into account by using an appropriate sublattice model.

January 4, 2022

Thermodynamic assessment of the Pd–Sc system

Zhenmin Du, Changrong Li, Lunwen Lü

Page range: 277-280

Abstract

The Pd–Sc system was critically assessed by means of the CALPHAD technique. The solution phases (liquid and face-centered cubic (Pd)) were modeled with the Redlich-Kister equation. The intermetallic compound PdSc, which has a homogeneity range, was treated as the formula (Pd,Va) Sc by a two-sublattice model with Pd and vacancies, denoted Va, on the first sublattice, whereas Sc on the second one; the others as stoichiometric compounds. A set of self-consistent thermodynamic parameters of the Pd–Sc system was obtained.

January 4, 2022

Heat content of liquid Fe –Cu–Si alloys formed in the melting treatment process of domestic waste incineration residue

Toshi Washizu, Tetsuya Nagasaka, Mitsutaka Hino

Page range: 281-287

Abstract

Some new melting processes for the ash have been developed to solve the problems on increasing volume of ash generated from municipal waste incinerators. The metal phase formed in this melting process generally consists of Fe –Cu – Si –P–C containing a small amount of other heavy metals, but their phase equilibria and physico-chemical properties are unknown. The present work aimed at determining the thermochemical properties of liquid Fe –Cu –Si alloys, which establish the basic system in this melting process. The heat contents of liquid Fe, Fe –Cu and Fe –Cu –Si alloys have been directly measured with a drop calorimeter at mainly 2073 K in the present work. The observed heat content and the enthalpy of mixing of the alloys were assessed by a thermodynamic model. The input energy which should be supplied to melt the metal phase in the new melting treatment process was also discussed.

January 4, 2022

A model of viscosity for liquid metals

S. Morioka, Bian Xiufang, Sun Minhua

Page range: 288-292

Abstract

We present a model to describe the viscosity of liquid metals with known physical properties. The model involves two adjustable parameters to the experimental data of the viscosity, but can be related to an effective atomic diameter and the coordination number of nearest-neighbor atoms in the liquid metals. The model is applied to eleven cases of mono-atomic liquid metals. The model is capable of describing the overall experimental data of the viscosity in a wide range of temperature, predicting the mean free paths of an atom in accord to the experimental interatomic distances in the liquid metals. An extension of this model to multi-component liquid metals is also suggested.

January 4, 2022

Umwandlungswärme einer NiTi-Gedächtnislegierung unter Last

Edson Paulo da Silva

Page range: 293-297

Abstract

Ziel der vorliegenden Arbeit war es, den Einfluss einer Last auf die Umwandlungswärme einer NiTi-Gedächtnislegierung zu untersuchen. Zur Durchführung dieser Messung anhand eines herkömmlichen Kalorimeters wurde ein spezieller Probenhalter entworfen, der eine Vordehnung während der kalorimetrischen Messung ermöglicht. Da unter festgehaltener Dehnung der Phasenübergang unter Last stattfindet, ließ sich auf diese Weise der Einfluss der Last auf die Umwandlungswärme untersuchen. Diese Untersuchung wurde auch mathematisch behandelt, und es wurde eine gute qualitative Übereinstimmung mit den Messergebnissen erhalten.

January 4, 2022

Study of magnetic properties of Ni –Fe –P and Ni –Fe –P–B chemical films

Lingling Wang, Weiqing Huang, Guifang Huang, Lihua Zhao

Page range: 298-302

Abstract

The magnetic properties of as-plated and heat-treated Ni – Fe –P and Ni –Fe –P–B films were investigated as a basis for developing new functional thin films. The amorphous Ni –Fe –P and Ni –Fe –P–B and crystalline Ni –Fe –P–B films were prepared by simply controlling the NaH 2 PO 2 concentration in the bath. The structure of all Ni –Fe –P films, prepared in an NaH 2 PO 2 concentration range of 18– 48 g/l, was amorphous, while the NaH 2 PO 2 concentration for the formation of amorphous Ni –Fe –P–B films ranged from 23 to 38 g/l. The increase of the Fe content is thought to be the reason for the increase in the atomic magnetic moment, and thus results in an increase in the saturation magnetization (Ms). The amorphous Ni –Fe –P films possess superior coercivity (Hc). Similar behavior can also be seen in the case of Ni –Fe –P–B films. The lower squarenesses of as-plated films, compared with those of annealed films, implies that the as-deposited films are inhomogenous. As the films were heated up to 400 °C, the homogeneity was obviously improved, and Ms decreased and Hc increased continuously for all the alloy films.

January 4, 2022

Geometrical modelling of a crystal grain in a weld of ferritic stainless steel

Janez Tušek, Dejan Arbi, Franc Markelj, Borut Zorc

Page range: 303-309

Abstract

The paper deals with modelling of the shape and size of a crystal grain in a butt joint of ferritic high-alloy stainless steel made by TIG welding without the addition of filler material. The optimum, maximum, and minimum current intensities and welding speeds were experimentally determined. The welding speed is mathematically described as a function of the welding-current intensity. On the basis of macro specimens taken from three different directions with regard to the welding direction, the grain shape, size and location in the weld with regard to the welding direction were established. Individual characteristic crystal grains are shown in space. The average grain size was determined and described mathematically as a function of the welding parameters.

January 4, 2022

Welding of heat-resistant 20% Cr – 5% Al steels

Janez Tušek, Alenka Kosmač, Uroš Nartnik, Dejan Arbi

Page range: 310-314

Abstract

The paper treats welding of heat-resistant ferritic stainless steels alloyed with approximately 20% Cr and 5% Al. The major part of the paper is dedicated to welding of 20% Cr – 5% Al steel with 3 mm in thickness. Welding was carried out with five different welding processes, i. e., manual metal-arc, MIG, TIG, plasma arc, and laser beam welding processes, using a filler material and using no filler material, respectively. The welded joints obtained were subjected to mechanical tests and the analysis of microstructure in the weld metal and the transition zone. The investigations conducted showed that heat-resistant ferritic stainless 20% Cr – 5% Al steel can be welded with fusion welding processes using a Ni-based filler material.

January 4, 2022

Finite element analysis of γ^′ directional coarsening in Ni-based superalloys

L. Zhou, S. X. Li, C. R. Chen, Y. C. Wang, Q. S. Zang, K. Lu

Page range: 315-321

Abstract

A three-dimensional anisotropic finite element analysis was performed to calculate the hydrostatic pressure, elastic strain energy density and von Mises stress associated with periodically arranged cubic γ′ precipitates in the γ matrix of Ni-based superalloys. Inhomogeneous and anisotropic elastic media are considered, the effects of different lattice misfit and external loads are investigated. The results show that the asymmetry of the hydrostatic pressure, the strain energy density and von Mises stress could be used to predict the γ′ directional coarsening. The contribution of hydrostatic pressure to the total driving force is smaller than that of von Mises stress and the elastic strain energy. The reason was briefly discussed.

January 4, 2022

Quantitative analysis of aluminium alloys using SIMS

C. J. Simensen, U. Södervall

Page range: 322-329

Abstract

A quantitative method for analysis of aluminium alloys using secondary-ion mass spectroscopy has been tested. The sensitivity factor, S x /Al , for several elements ( x ) was determined using homogenised Al materials. Also other Al alloys were analysed using almost identical instrumental conditions. It was found that since the materials investigated contained much Fe and Mg, they contributed with molecular interferences when measuring Ti and Ni. The results showed that while keeping constant the analytical parameters, it was possible to use sensitivity factors S x /Al with a good accuracy for quantification of the elements which were mainly solved in the matrix. The results indicated that the metal was still slightly inhomogeneous in several elements even after annealing at 550 °C for one week. Another important factor is that the emission spectrometer has a high relative standard deviation for the analysis below 5 wt.ppm. This resulted in variations in the calculated sensitivity factor for elements like Na and Ca determined for different materials. The new method was used for calculating concentration profiles of elements in Al materials as a function of the sputtering depth. Samples of alloy AA5182 were homogenised for one week at 5 different temperatures between 450 and 580 °C. The solubility of K, Na, and B in Al was determined. They were of the order 0.2 wt.ppm Na, 0.3 wt.ppm B and 0.04 wt.ppm K at 550 °C.

January 4, 2022

Effect of the particle size on the mechanical properties of 60 vol.% SiC_p reinforced Al matrix composites

H. Ahlatci, E. Candan, H. Çimenoğlu

Page range: 330-333

Abstract

The effect of the reinforcing particle size on the mechanical properties of 60 vol.% SiC reinforced aluminium matrix composites produced by the pressure infiltration technique was examined by compression, impact and wear tests. The compression strength and the impact resistance decreased with increasing reinforcing particle size. The composites exhibited different abrasion behaviour depending on the size of abrasive Al 2 O 3 grains. On fine abrasive Al 2 O 3 grains (85 μm), the abrasion resistance increased with increasing reinforcing SiC particle size. The contrary result was obtained on coarse abrasive Al 2 O 3 grains (250 μm). The wear tests conducted on M2 quality tool steel revealed that reinforcing of aluminium with coarse SiC particles has a very beneficial effect on the wear resistance with respect to fine reinforcing SiC particles.

Notifications/Mitteilungen

January 4, 2022

Personal/Personelles

Page range: 334-336

About this journal

The International Journal of Materials Research (IJMR) publishes original high quality experimental and theoretical papers and reviews on basic and applied research in the field of materials science and engineering, with focus on synthesis, processing, constitution, and properties of all classes of materials. Particular emphasis is placed on microstructural design, phase relations, computational thermodynamics, and kinetics at the nano to macro scale. Contributions may also focus on progress in advanced characterization techniques.
All articles are subject to thorough, independent peer review.

Volume 93 Issue 4

Issue of International Journal of Materials Research

Frontmatter

59Fe Grain boundary diffusion in nanostructured γ-Fe–Ni

Part I: Radiotracer experiments and Monte-Carlo simulation in the type-A and B kinetic regimes

Abstract

59Fe Grain boundary diffusion in nanostructured γ-Fe–Ni

Part II: Effect of bimodal microstructure on diffusion behavior in type-C kinetic regime

Abstract

Thermodynamic assessment of the Cu–Ti system taking into account the new stable phase CuTi3

Abstract

Thermodynamic assessment of the Pd–Sc system

Abstract

Heat content of liquid Fe –Cu–Si alloys formed in the melting treatment process of domestic waste incineration residue

Abstract

A model of viscosity for liquid metals

Abstract

Umwandlungswärme einer NiTi-Gedächtnislegierung unter Last

Abstract

Study of magnetic properties of Ni –Fe –P and Ni –Fe –P–B chemical films

Abstract

Geometrical modelling of a crystal grain in a weld of ferritic stainless steel

Abstract

Welding of heat-resistant 20% Cr – 5% Al steels

Abstract

Finite element analysis of γ′ directional coarsening in Ni-based superalloys

Abstract

Quantitative analysis of aluminium alloys using SIMS

Abstract

Effect of the particle size on the mechanical properties of 60 vol.% SiCp reinforced Al matrix composites

Abstract

Personal/Personelles

⁵⁹Fe Grain boundary diffusion in nanostructured γ-Fe–Ni

⁵⁹Fe Grain boundary diffusion in nanostructured γ-Fe–Ni

Thermodynamic assessment of the Cu–Ti system taking into account the new stable phase CuTi₃

Finite element analysis of γ^′ directional coarsening in Ni-based superalloys

Effect of the particle size on the mechanical properties of 60 vol.% SiC_p reinforced Al matrix composites