Properties Of Intermetallic Compounds Research Articles

Crystal structure, Chemical Bonding, and Magnetism of α-Fe6Ga5: How Local Interactions Shape the Structure and Properties of Intermetallic Compounds.

α-Fe6Ga5 was synthesized from the elements as a polycrystalline powder. Its crystal structure was redetermined by high-resolution powder X-ray diffraction, which showed a complex monoclinic structure of the Fe6Ge5 type. The determined lattice parameters (a = 10.08380(6) Å, b = 7.97071(5) Å, c = 7.70489(5) Å, and β = 108.3062(2)°) differ notably from the previous reports. Despite possessing the same structure type as Fe6Ge5, α-Fe6Ga5 displays several distinctive features, such as short Ga-Ga bonds and distorted Fe layers. According to magnetization measurements, α-Fe6Ga5 is a soft ferromagnet with a high Curie temperature of 760 K, which is in stark contrast to the antiferromagnetic behavior of Fe6Ge5 reported in the literature. The electronic structure of α-Fe6Ga5 was studied theoretically using density functional theory-calculations, which showed the pronouncedly covalent character of the short Fe-Ga and Ga-Ga bonds. Similar calculations were performed for Fe6Ge5, which revealed stronger Fe-Ge interactions, which preclude the formation of short Ge-Ge bonds. In both cases, the theoretical calculations showed ferromagnetic instability, which leads to ferromagnetic ordering only in the case of α-Fe6Ga5, likely due to the different nature of Fe-Ga-Fe and Fe-Ge-Fe superexchange interactions.

Investigating the influence of Ni interlayers on Fe/Al laser welded joints: A first-principles study

201 Stainless steel and 5052 aluminium alloy were laser lap welded, both with and without a Ni foil interlayer. The Ni addition enhanced the metallurgical reaction between molten stainless steel/aluminium, resulting in the formation of the Al0.9Ni1.1 intermetallic compound. First-principles calculations estimated the equilibrium lattice and properties of IMCs (intermetallic compounds). A structural model of the interface revealed that the bonding strengths of Al/IMC and Fe/IMC interfaces surpassed those of IMC/IMC interfaces, making cracks prone to initiate and expand at the latter. Joints without Ni reached a max tensile shear strength of 74.5 N/mm, while those with Ni increased significantly to 101.8 N/mm, marking a substantial 36.6% enhancement.

A Critical Review on the Properties of Intermetallic Compounds and Their Application in the Modern Manufacturing

AbstractAdvancement in modern manufacturing processes is allowing researchers to develop new alloy configurations for different applications to reduce weight and increase efficiency. Many alloy combinations are produced that randomly generate different phases of intermetallic compounds (IMCs) in the structure during manufacturing which show unique mechanical and chemical properties. But, the fundamental knowledge of different IMCs is scattered across the material research domain. Thus, in this review, the crystal structures of IMCs are thoroughly discussed which are having structural and functional applications. Furthermore, the issues associated with the dissimilar Fe‐Al, Fe‐Ni, and Ni‐Al systems via modern manufacturing processes such as arc additive manufacturing have been discussed. Moreover, detailed knowledge of ferro‐nickel, nickel‐aluminides, and ferro‐aluminides formed at the interface during the dissimilar deposition in modern manufacturing is provided. Currently, a few transition metal IMCs and some Heusler alloys, are the most promising and are used in applications. The addition of a third alloying element provides the broadening effect on the phase domain of a specific IMC. Furthermore, it has been observed that modern manufacturing processes such as additive manufacturing and others are new and advanced manufacturing technologies used for dissimilar metal deposition, which can control the IMCs in a more favorable direction.

Formation and nanomechanical properties of intermetallic compounds in electrodeposited Cu–Sn–Co multilayers

The properties of the intermetallic compounds (IMCs) formed at the interface between the solder and the Under Bump Metallization (UBM) are crucial for the reliability of solder joints. Cobalt (Co) is a potential candidate for UBM since it can act as a diffusion barrier and hence can improve the performance of tin-based solder joints. Growth kinetics, mechanism of formation, and properties of IMC in the copper-tin-cobalt (Cu–Sn–Co) system that is encountered with Co UBM are presented in this paper. Cu–Sn–Co systems were prepared by electrodeposition of Cu, Sn and Co multilayers on Cu substrates followed by reflow at 250 °C for varying durations (1–30 min). Microscopic observation revealed the formation of defect-free (Co,Cu)Sn3, crack-containing (Cu,Co)6Sn5 and thin irregular Cu3Sn IMCs after 1 min reflow. As reflow duration increased, (Co,Cu)Sn3 and Cu3Sn grew at the expense of (Cu, Co)6Sn5. The consumption of the entire Sn layer after 1 min and the calculated effective interdiffusion coefficient of (Co,Cu)Sn3 suggested that the growth of (Co,Cu)Sn3 after 1 min is controlled by solid-state diffusion of Sn. The average Young’s Modulus values of (Co,Cu)Sn3, (Cu,Co)6Sn5 and Cu3Sn are 99.5 ± 3.2 GPa, 110.8 ± 7.3 GPa and 109.4 ± 0.3 GPa, respectively, while the nanohardness values are 4.15 ± 0.34 GPa, 6.74 ± 0.62 GPa and 4.96 ± 1.09 GPa, respectively. Increasing the reflow duration in the Cu–Sn–Co system is expected to improve the performance of the solder joint, through the replacement of the crack-containing (Cu,Co)6Sn5 by the defect-free (Co,Cu)Sn3.

Special Issue “Intermetallic Compound”

This Special Issue collects ten articles related to the broadly understood physical properties of intermetallic compounds [...]

Multicomponent Metal Hydride Materials for Hydrogen Energy Storage Systems

This paper presents the results of experimental studies of new hydrogen absorbing materials based on AB5 type alloys used for solid-phase hydrogen storage. The crystal structures, morphology, and hydrogen absorption properties of the new prepared samples were investigated. The effect of different metal additives on the properties of intermetallic compounds was studied

Influence of hot isostatic pressing on structure, phase composition and mechanical properties of intermetallic compounds on the base of Ti – Al – Nb – Mo – Cr – Zr system

Influence of hot isostatic pressing on structure, phase composition and mechanical properties of intermetallic compounds on the base of Ti – Al – Nb – Mo – Cr – Zr system

Elastic and mechanical properties of Mg3Rh intermetallic compound: An ab initio study

In this work, density functional theory plane-wave pseudo potential method, with local density approximation (LDA) and generalized gradient approximation (GGA) are used to investigate the structural, elastic, mechanical and thermodynamic properties of the intermetallic compound Mg3Rh. Comparison of the calculated equilibrium lattice constants and experimental data shows very good agreement. The elastic constants were determined from a linear fit of the calculated stress-strain function according to Hooke's law. From the elastic constants, the bulk modulus B, shear modulus G, Young's modulus E, Poisson's ratio σ, anisotropy factor A, the ratio B/G and the hardness parameter H for Mg3Rh compound are obtained. Our calculated elastic constants indicate that the ground state structure of Mg3Rh is mechanically stable. The calculation results show that this intermetallic crystal is stiff, elastically anisotropic and ductile material. The sound velocities and Debye temperature are also predicted from elastic constants. This is the first quantitative theoretical prediction of these properties.

HYDROGEN SORPTION PROPERTIES OF INTERMETALLIC COMPOUNDS La3-xMgxNi9

To increase the hydrogen mass in intermetallides of type LaNi 3 proposed to replace part of the La on Mg. Alloys of composition La 3- x Mg x Ni 9 ( x = 1, 1.1 and 1.2) were prepared. For this first lanthanum-nickel alloys were obtained by arc melting of mixtures of high purity La and Ni in an atmosphere of argon. These alloys were pulverized in a planetary ball mill with the addition of the necessary amount of the magnesium powder. Then the resulting homogeneous mixture was compressed into tablets, wrapped in tantalum foil, placed in a steel pipe and a homogenization annealing was performed at 950 °C for 6 hours. The thus prepared alloys consisted of 70–80 wt.% of the intermetallic compound phase with the structural type PuNi 3 and impurity phases La 4 MgNi 19 and LaNi 5 . The hydrogen sorption properties of intermetallic compounds prepared were studied. It was established that the isotherms La 3- x Mg x Ni 9 – H 2 have one plateau of phase transition, indicating the formation of only one hydride phase with hydrogen content of 1.58 wt.% (La 2 MgNi 9 H x ), 1.52 wt.% (La 1.9 Mg 1.1 Ni 9 H x ) and 1.5 wt.% (La 1.8 Mg 1.2 Ni 9 H x ). At that the equilibrium pressure is increased by rise the magnesium content in the sample. The variations in the enthalpy at dehydrogenation are calculated and it is established the rise of the thermal effect of the reaction with increasing magnesium content.

Structural Size Effect on Mechanical Behavior of Intermetallic Material in Solder Joints: Experimental Investigation

The elastic and plastic mechanical properties of intermetallic compound (IMC) phases of a lead-free Sn3.5Ag/Cu-substrate soldering system are investigated in different sized joints using nano-indentation. The specimens were prepared using solid–liquid interdiffusion soldering process with joint sizes ranging from 15 to 450 μm. Solder joints were subjected to 360 °C soldering temperature for 20 min and then air cooled to room temperature to create testable IMCs thicknesses. Nano-indentation was used to extract the elastic and plastic properties of Cu6Sn5, Cu3Sn, and Ag3Sn IMCs and β-tin and copper materials. Cu–Sn IMCs formed in specimens with smaller joint size show higher elastic modulus, hardness, and yield strength and lower work hardening exponent. This was attributed to the dimensional constraints associated with decreasing joint size and the local stresses developed during fabrication in joints with different sizes. Local elastic modulus and hardness of single grains of Cu6Sn5 were obtained using a combination of nano-indentation and electron backscatter diffraction (EBSD) techniques. Grains with c-axis at a 45 deg angle with respect to the nano-indentation loading direction show higher elastic modulus (∼8.70% higher) and hardness (8.85% higher) compared to the grains that have a c-axis that is almost perpendicular to the nano-indentation loading direction.

転位の動的振る舞いと金属間化合物の力学特性

転位の動的振る舞いと金属間化合物の力学特性

Phase transitions as a function of material constants and temperature in intermetallic compounds of the terfenol-D type

A model of magnetic and magnetoelastic properties of intermetallic compounds has been considered with the inclusion of the influence of the “giant” magnetoelastic coupling and the biquadratic exchange interaction. The phase transitions as a function of material constants and temperature have been investigated in the framework of the proposed model. It has been demonstrated that the ferromagnetic and quadrupole phases can be formed in the system under consideration. In this case, the phase transition between these phases is a first-order transition and occurs through the intermediate, i.e., quadrupole-ferromagnetic, state. The dependences of the phase transition temperature on the Heisenberg and biquadratic exchange interaction constants have been obtained for compounds of the terfenol-D type.

Yttrium-doped nanocrystalline Ni4Mo: ultrahigh strength and high ductility combined with useful intermetallic properties

We show that bulk nanocrystalline Ni4Mo can be synthesized by doping with small but critical concentrations of Y. Two alloys are included in the study with compositions of Ni4Mo and Ni4Mo + 0.01 wt% Y. Microstructural features derived from transmission electron microscopy observations are correlated with room-temperature tensile properties. Yttrium-doped Ni4Mo is found to have room-temperature yield strength in excess of 800 MPa and tensile elongation to failure of about 40% while simultaneously retaining other useful physical and chemical properties of intermetallic compounds. Twinning rather than slip is found to be the predominant deformation mechanism, which is correlated with the superlattice structure of Ni4Mo. Since deformation by twinning is polarized, this is expected to enhance the fatigue life.

115 めっき錫バンプと銅薄膜配線間金属間化合物の機械特性(学生賞III)

115 めっき錫バンプと銅薄膜配線間金属間化合物の機械特性(学生賞III)

143 鉛フリーはんだ/めっき銅薄膜金属間化合物の機械的特性(材料力学III)

143 鉛フリーはんだ/めっき銅薄膜金属間化合物の機械的特性(材料力学III)

203 鉛フリーはんだ/めっき銅薄膜金属間化合物の機械的特性(材料力学I,材料力学)

203 鉛フリーはんだ/めっき銅薄膜金属間化合物の機械的特性(材料力学I,材料力学)

金属間化合物中の過飽和熱空孔の自己組織化と機械的性質への影響(OS11f 材料の組織・強度に関するマルチスケールアナリシス)

金属間化合物中の過飽和熱空孔の自己組織化と機械的性質への影響(OS11f 材料の組織・強度に関するマルチスケールアナリシス)

Enhancement of high temperature thermoelectric properties of intermetallic compounds based on a Skutterudite IrSb3 and a half-Heusler TiNiSb

Phonon glass and electron crystal (PGEC) thermoelectric materials have been expected to be a new class of thermoelectric materials for high temperature applications. Among the efforts to optimize the high temperature thermoelectric properties of various PGEC thermoelectric materials, recent experimental works on the Skutterudite IrSb3 and half-Heusler TiNiSb intermetallic compounds are presented herein by which the material design concept for high energy conversion efficiency, i.e. a high figure of merit, is suggested. It is revealed that the thermoelectric efficiency of IrSb3 can be increased by the decrease of lattice thermal conductivity due to the rattling effect of La atoms filled in the structural vacancies of the Skutterudite crystal structure. In the half-Heusler TiNiSn, high temperature thermoelectric properties are improved by Hf substitution to the Ti sites by reducing lattice thermal conductivity and also by Sb doping to increase power factor. It is concluded that the proper alloy designing for controlling crystal structure and carrier concentration could enable these intermetallic compounds to exhibit a high potential for elevated temperature thermoelectric applications.

The thermodynamic properties of intermetallic compounds and solid solutions of Cu-Zr system

The thermodynamic properties of crystalline copper–zirconium alloys are investigated in a wide range of temperatures of 701–1740 K and compositions of 5.1–97.3 at. % Zr using the Knudsen method of mass-spectrometry, including the technique based on the initiation and study of equilibria involving volatile products. The equilibrium of zirconium with KF additives is studied to achieve minimal temperatures of measurements. The obtained data are used to produce, for the first time, a complete thermodynamic description of all intermetallic compounds, as well as solid solutions of copper in bcc-Zr, in the range from temperatures of crystallization of amorphous alloys to liquidus temperatures. The accuracy and reliability of the obtained thermodynamic functions are confirmed by the coincidence of the results of measurements in studying samples of different compositions under different experimental conditions (the material of the effusion cell, the size of the effusion orifice, the type of reaction additive), as well as by agreement of the results with one another and with independent experimental data on phase equilibria. The evidence of the existence of Cu2Zr and Cu5Zr8 phases is obtained, and the regularities of phase transformations in crystalline copper–zirconium alloys are revealed.

Composition control of a TiAl melt during the induction skull melting (ISM) process

The properties of intermetallic compounds are sensitive to alloying composition determined by the melting process. This article describes research that aims to control the composition of a TiAl melt during the ISM process. Firstly, the vapor pressures of Al and Ti in the TiAl melt were established and the results show that P Al/ P Ti is over 300. The ratio points out that Al will evaporate more predominantly than Ti in the TiAl melt during the vacuum melting process. Then, the mass transport coefficient K and the mass evaporation rate N m were calculated. The vacuum pressure has the same influence on K and N m. There are two contraflexure points of the vacuum pressure, namely the critical point and the impeding point. When the vacuum pressure surpasses the impeding point, the evaporation of Al can be neglected. When the vacuum pressure is below the critical point, the evaporation of Al will take on a free evaporation and the Al content will decreases to 40at% from 48at%. The calculated results were compared with the experimental data, which verified the calculation results.