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Showing papers on "Alloy published in 1997"


Journal ArticleDOI
TL;DR: In this article, an electrochemical and in situ x-ray diffraction experiments on a variety of tin oxide based compounds; SnO,,,, and glass, as cathodes opposite lithium metal in a rechargeable Li-ion coin cell were conducted.
Abstract: We report our electrochemical and in situ x‐ray diffraction experiments on a variety of tin oxide based compounds; SnO, , , and glass, as cathodes opposite lithium metal in a rechargeable Li‐ion coin cell. These materials demonstrate discharge capacities on the order of 1000 mAh/(g Sn), which is consistent with the alloying capacity limit of 4.4 Li atoms per Sn atom, or 991 mAh/(g Sn). These materials also demonstrate significant irreversible capacities ranging from 200 mAh/(g active) to 700 mAh/(g active). In situ x‐ray diffraction experiments on these materials show that by introducing lithium, lithium oxide and tin form first, which is then followed by the formation of the various Li‐Sn alloy phases. When lithium is removed the original material does not reform. The ending composition is metallic tin, presumably mixed with amorphous lithium oxide. The oxygen from the tin oxide in the starting material bonds irreversibly with lithium to form an amorphous matrix. The Li‐Sn alloying process is quite reversible; perhaps due to the formation of this lithia "matrix" which helps to keep the electrode particles mechanically connected together.

1,370 citations


Journal ArticleDOI
TL;DR: In this paper, a set of many-body interatomic potentials has been developed for the Fe-Cu system, including modifications to ensure suitability for simulating atomic collisions at high energy.
Abstract: The behaviour of copper atoms in dilute solution in α-iron is important for the microstructural changes that occur in ferritic pressure vessel steels under fastneutron irradiation. To investigate the properties of atomic defects that control this behaviour, a set of many-body interatomic potentials has been developed for the Fe—Cu system. The procedures employed, including modifications to ensure suitability for simulating atomic collisions at high energy, are described. The effect of copper on the lattice parameter of iron in the new model is in good agreement with experiment. The phonon properties of the pure crystals and, in particular, the influence of the instability of the metastable, bcc phase of copper that precipitates during irradiation are discussed. The properties of point defects have been investigated. It is found that the vacancy has lower formation and migration energy in bcc copper than in α-iron, and the self-interstitial atom has very low formation energy in this phase of coppe...

603 citations


Journal ArticleDOI
TL;DR: In this article, a Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy, machined into 7 mm wide, 38 mm thick compact-tension specimens and fatigue precracked following standard procedures, revealed fracture toughnesses in the fully amorphous structure of K(lc)similar to 55 MPa root m, i.e., comparable with that of a high-strength steel or aluminum ahoy.
Abstract: The recent development of metallic alloy systems which can be processed with an amorphous structure over large dimensions, specifically to form metallic glasses at low cooling rates (similar to 10 K/s), has permitted novel measurements of important mechanical properties. These include, for example, fatigue-crack growth and fracture toughness behavior, representing the conditions governing the subcritical and critical propagation of cracks in these structures. In the present study, bulk plates of a Zr41.2Ti13.8Cu12.5Ni10Be22.5 alloy, machined into 7 mm wide, 38 mm thick compact-tension specimens and fatigue precracked following standard procedures, revealed fracture toughnesses in the fully amorphous structure of K(lc)similar to 55 MPa root m, i.e., comparable with that of a high-strength steel or aluminum ahoy. However, partial and full crystallization, e.g., following thermal exposure at 633 K or more, was found to result in a drastic reduction in fracture toughness to similar to 1 MPa root m, i.e., comparable with silica glass. The fully amorphous alloy was also found to be susceptible to fatigue-crack growth under cyclic loading, with growth-rate properties comparable to that of ductile crystalline metallic alloys, such as high-strength steels or aluminum alloys; no such fatigue was seen in the partially or fully crystallized alloys which behaved like very brittle ceramics. Possible micromechanical mechanisms for such behavior are discussed.

423 citations


Journal ArticleDOI
29 Aug 1997-Science
TL;DR: In this paper, the composition and structure of the β-phase of an aluminum-magnesium-silicon alloy were determined using high-resolution electron microscopy images, and the structure was refined with electron nanodiffraction data (overall R value of 3.1 percent) with the use of a recently developed least squares refinement procedure.
Abstract: Precipitation hardening, in which small particles inhibit the movement of dislocations to strengthen a metal, has long been used to improve mechanical strength, especially of aluminum alloys. The small size of precipitates and the many possible variants of the orientation relation have made their structural determination difficult. Small precipitates in commercial aluminum-magnesium-silicon alloys play a crucial role in increasing the mechanical strength of these alloys. The composition and structure of the β” phase in an aluminum-magnesium-silicon alloy, which occur as precipitates (typically 4 nanometers by 4 nanometers by 50 nanometers) and are associated with a particularly strong increase in mechanical strength, were determined. Element analysis indicates that the composition is Mg 5 Si 6 . A rough structure model was obtained from exit waves reconstructed from high-resolution electron microscopy images. The structure was refined with electron nanodiffraction data (overall R value of 3.1 percent) with the use of a recently developed least squares refinement procedure in which dynamic diffraction is fully taken into account.

330 citations


Journal ArticleDOI
TL;DR: In this paper, the authors used high vacuum, containerless, electrostatic levitation process to study the undercooling and crystallization kinetics of a bulk glass forming Zr-Ti-Cu-Ni-Al alloy.
Abstract: High vacuum, containerless, electrostatic levitation process has been used to study the undercooling and crystallization kinetics of a bulk glass forming Zr-Ti-Cu-Ni-Al alloy. The oxygen impurity level in the alloy has been found to play a crucial role in the crystallization kinetics of the undercooled melt. Overheating the melt above a critical threshold temperature results in enhancement subsequent undercooling. This crucial threshold temperature is found to be a function of the overall oxygen content of the alloy direct measurement of the time-temperature-transformation (TTT) diagram for crystallization of the undercooled melt made following initial overheating above the threshold temperature show a strong dependence on overall oxygen concentration. An explanation of these observations is proposed.

311 citations


Journal ArticleDOI
TL;DR: The glass-forming ability of a Pd 4 Cu 30 Ni 10 P 20 alloy was found to increase significantly by B 2 O 3 flux treatment, as is evidenced by the decrease in the critical cooling rate from 1.57 K/s in the non-fluxed state to 0.100 K/m in the fluxed state as mentioned in this paper.
Abstract: The glass-forming ability of a Pd 4 Cu 30 Ni 10 P 20 alloy was found to increase significantly by B 2 O 3 flux treatment, as is evidenced by the decrease in the critical cooling rate from 1.57 K/s in the non-fluxed state to 0.100 K/s in the fluxed state. The flux treatment also causes the extension of the supercooled liquid region by the increase in the onset temperature of crystallization (T x ). The effect of the flux treatment is presumably due to the increase in the thermal stability of the supercooled liquid by the suppression of heterogeneous nucleation. The critical cooling rates in the non-fluxed and fluxed states for a Pd 40 Ni 40 P 20 alloy are measured to be 128 and 0.167 K/s, respectively, both of which are larger than those for the Pd-Cu-Ni-P alloy. The use of the molten Pd-Cu-Ni-P alloy subjected to the flux treatment enabled the production of bulk amorphous alloys in cylindrical forms of 50 to 72 mm in diameter and 52 to 75 mm in length. The glass transition temperature (T g ) and T x values of the bulk amorphous alloys are the same as those for the melt-spun amorphous ribbon prepared from the fluxed molten alloy. The success of synthesizing an amorphous alloy of 72 mm in diameter is encouraging both for the future development of basic science of bulk amorphous alloys and for their engineering application.

303 citations


Journal ArticleDOI
01 Aug 1997-JOM
TL;DR: In this article, the microstructure and mechanical properties of H13 alloy are described using the direct metal deposition (DMD) technique, which is the state-of-the-art for die and tool manufacturing.
Abstract: The rapid prototyping process has reached the stage of rapid manufacturing via the direct metal deposition (DMD) technique. The DMD process is capable of producing three-dimensional components from many of the commercial alloys of choice. H13 tool steel is a difficult alloy for deposition due to residual stress accumulation from martensitic transformation; however, it is the material of choice for the die and tool industry. This article reviews the state of the art of DMD and describes the microstructure and mechanical properties of H13 alloy deposited by DMD.

254 citations


Journal ArticleDOI
TL;DR: In this article, the microstructural properties of amorphous silicon (a-Si) alloy solar cells were investigated using high-resolution transmission electron microscopy (TEM) and Raman spectroscopy.
Abstract: We investigate why high levels of hydrogen dilution of the process gas lead to enhanced light soaking stability of amorphous silicon (a-Si) alloy solar cells by studying the microstructural properties of the material using high-resolution transmission electron microscopy (TEM) and Raman spectroscopy. The TEM results show that a-Si alloy (with or without hydrogen dilution) is a heterogeneous mixture of amorphous network and linear-like objects that show evidence of order along their length. The volume fraction of these ordered regions increases with increasing hydrogen dilution.

246 citations


Journal ArticleDOI
TL;DR: In this paper, the susceptibility to pitting corrosion of pure aluminium and 2024 T351 alloy in 0.1 mol l−1 Na2SO4 solutions containing chloride ions was investigated by a statistical approach.

212 citations


Journal ArticleDOI
TL;DR: In this paper, the peak hardness of alloy powders is associated with the concentration of the alloying element initially in solid solution in the powders and the strengthening observed is interpreted in terms of theories of precipitation and dispersion strengthening.

204 citations



Journal ArticleDOI
TL;DR: In this article, a ternary phase was observed in binary Mg-1Ca-1Zn alloy, which appears isomorphous with Mg2Ca (space group P63/mmc).

Journal ArticleDOI
TL;DR: In this paper, the incorporation of iron reduced the overpotential required for oxygen evolution by as much as 300 mV at a current density of 100 mA/cm 2 compared to undoped nickel oxide under similar conditions.
Abstract: Iron-doped nickel oxide films were deposited by reactive sputtering from elemental and alloy targets in a 20% oxygen/argon atmosphere and were characterized for use as oxygen evolution catalysts. The incorporation of iron reduced the overpotential required for oxygen evolution by as much as 300 mV at a current density of 100 mA/cm 2 compared to undoped nickel oxide deposited under similar conditions. Tafel slopes were reduced from 95 mV/dec in undoped NiO x films to less than 40 mV/dec for films containing 1.6 to 5.6 mole percent (m/o) iron, indicating a change in the rate-limiting step from the primary discharge of OH ions to the recombination of oxygen radicals. Resistivity, structural, and compositional measurements indicate that high oxygen content is necessary to gain the full benefit of the iron dopant. Initial tests in KOH indicate excellent long-term stability. A film deposited from the FeNi alloy target, which exhibited low oxygen overpotentials and a Tafel slope of 35 mV/dec, had not degraded appreciably following more than 7000 h of operation at an anodic current density of 20 mA/cm 2 . Taken together, the low oxygen evolution reaction overpotentials, the excellent stability in KOH, and the relative insensitivity to iron content indicate that reactively sputtered iron-doped nickel oxide is promising as an oxygen catalyst.

Journal ArticleDOI
TL;DR: In this article, Ni-base superalloys were exposed isothermally in air at temperatures between 750° and 1000°C and also under cyclic conditions at 1000°c.
Abstract: Several commercially available Ni-base superalloys were exposed isothermally in air at temperatures between 750° and 1000°C and also under cyclic conditions at 1000°C. The kinetics of oxidation were determined and the scales were analyzed by electron microscopy and X-ray diffraction. Thin adherent chromia-rich scales formed on the alloys at 750°C after 1000 hr. Although Waspaloy showed the lowest weight gain in this test, it also showed the deepest internal corrosion due to oxidation of the grain-boundary carbides. At temperatures up to 1000°C the external scales were also chromia-rich but there was greater internal corrosion. Titanium in the alloys oxidized, diffusing through the chromia scale to form faceted rutile (TiO2) grains at the surface as well as forming TiO2 and TiN internally. The amount of rutile at the oxide surface increased with temperature and alloy Ti concentration. Alumina formed as discrete internal oxides below the chromia scale, although Astroloy when oxidized isothermally at 1000°C developed a semicontinuous internal layer of alumina due to its higher Al content. Under cyclic conditions Astroloy formed a thicker, less-protective scale of transition oxides probably due to its lower Cr content.

Journal ArticleDOI
TL;DR: In this paper, a wide supercooled liquid region before crystallization and good soft magnetic properties were found for Fe-based amorphous alloys in Fe-Co-Ni-Zr-B system.
Abstract: New Fe-based amorphous alloys in Fe-Co-Ni-Zr-B system exhibiting a wide supercooled liquid region before crystallization and good soft magnetic properties were found to be formed by melt spinning. The composition range of the amorphous (Fe 1-x-y Co x Ni y ) 70 Zr 10 B 20 alloys with the wide supercooled liquid region above 50 K extends from 0 to 36 at%Co and 0 to 30%Ni and the largest value of the supercooled liquid region defined by the difference between the glass transition temperature (T g ) and crystallization temperature (T x ), ΔT x ( = T x - T g ) is 68 K for Fe 56 Co 7 Ni 7 Zr 10 B 20 . The crystallization from the supercooled liquid of the Fe 56 Co 7 Ni 7 Zr 10 B 20 alloy upon continuous heating occurs through a single stage and the resulting crystallized structure consists of α-Fe, Fe2Zr and Fe 3 B phases containing Co and Ni elements. These Fe-based amorphous alloys exhibit good soft magnetic properties and the saturation magnetization, coercive force, permeability at I kHz and Curie temperature are respectively 0.96 T, 2.41 A/m, 17700 and 567 K for the amorphous Fe 56 Co 7 Ni 7 Zr 10 B 20 alloy annealed for 600 s at 750 K. The finding of the Fe-based amorphous alloys with good soft magnetic properties and high thermal stability of the supercooled liquid is important for future development of ferromagnetic bulk amorphous alloys.

Journal ArticleDOI
TL;DR: In this paper, the presence of rare-earth oxides in a ternary magnesium alloys was investigated by transmission electron microscopy using ultramicrotomed film sections.
Abstract: Oxides on ternary magnesium alloys MgAlZn and MgAlRE were investigated by transmission electron microscopy using ultramicrotomed film sections. These films have a three-layered structure, similar to pure Mg and binary MgAl alloys, characterized by a hydrated inner layer, a thin and dense intermediate region, and a platelet-like outer layer. Zinc and rare-earth elements present in the two types of ternary alloys become incorporated in the oxide film so as to increase its stability in an aqueous environment, in particular by reducing hydration and increasing resistance to magnesium egress of the inner layer, which is responsible for the passivity of the surface. The apparent presence of trace amounts of rare-earth oxides in the film is particularly effective in improving passivity of the surface and, thereby, the corrosion resistance of MgAlRE alloys. The presence of aluminum together with rare-earth elements (RE) in the alloy is an essential factor in obtaining these results.

Journal ArticleDOI
TL;DR: In this paper, the formation of twins, α'- and £-martensite during plastic deformation was analysed by optical microscopy, X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscope (TEM).
Abstract: Deformation twinning, martensitic phase transformation and mechanical properties of austenitic Fe-(15-30)wt%Mn alloys with additions of aluminium and silicon have been investigated. Tensile tests were carried out at different strain rates and temperatures. The formation of twins, α ' - and £-martensite during plastic deformation was analysed by optical microscopy, X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The stacking fault energy γ fcc and the free energy ΔG γ-e for the γ→e phase transformation were calculated using the regular solution model. It is known that additions of aluminium increase γ fcc and therefore strongly suppress the γ→e transformation while silicon decrease γ fcc and sustains the γ-e transformation. The γ→e phase transformation takes place in alloys with γ fcc 20 mJ/m 2 . The stacking fault energy of the Fe-25Mn-3Si-3Al alloy was calculated as a function of temperature and related with microstructural changes of the strained sample at different temperatures. These steels with reduced density of about 7,3 g/cm -3 combine high tensile ductility up to 80 % at high strain rates with true tensile strength of about 1000 MPa. The excellent plasticity induced by twinning and additional phase transformation up to extremely high strain rates of about e = 10 3 s -1 results in an extraordinary shock resistence and enables deep drawing and backward extrusion operations of parts with complex shapes and high production rates.

Journal ArticleDOI
TL;DR: In this article, the passive film formed on the Ti-6%Al-4% V extra low interstitial alloy consists mainly of TiO2, A1 2 O 3 and small amounts of V oxide.
Abstract: The corrosion resistance of implant alloys was investigated by anodic polarization measurements in a pseudo physiological solution. Role of alloying elements in passive film formed on implant alloys by the anodic polarization was also examined with X-ray photoelectron spectroscopy (XPS). Passivity zones of SUS316L stainless steel and Co-Cr alloys are narrow, and a rapid increase in the current density is observed from a low potential as compared to Ti alloys. The passive current density of Ti-15%Zr-4%Nb-2%Ta-0.2%Pd alloy (mass%) is very low. Effects of protein and dissolved oxygen with 90%N 2 + 5%CO 2 + 5% O 2 gas bubbling on anodic polarization curves are not detected. The passive film formed on the Ti-6%Al-4% V extra low interstitial alloy consists mainly of TiO2, A1 2 O 3 and small amounts of V oxide. Passive films on the Ti-15%Zr-4%Nb-2%Ta-0.2%Pd and Ti-15% Sn-4%Nb-2%Ta-0.2%Pd alloys consist of TiO 2 , ZrO 2 , SnO 2 , Nb 2 O 5 , Ta 2 O 5 and PdO or Pd. XPS spectra from the Co-Cr alloy and SUS316L stainless steel show peaks of Cr2O3, CoO, Fe oxide, Mo oxide, Ni, Co, Fe, Mo and Cr. As Ni, V and Co are strong cytotoxic elements, it was found that biocompatibility of SUS 316L, Co-Cr, Ti-6%Al-4% V ELI alloys become lesser after a long time use in the living body. The thickness of the passive film on Ti alloys is thinner than that of Co-Cr alloy. Passive film formed on the Ti-15%Zr-4%Nb-2%Ta-0.2%Pd alloy is strong and stable.

Journal ArticleDOI
Hideki Iba1, Etsuo Akiba
TL;DR: In this article, a new hydrogen-absorbing alloy, consisting of a nano-structure having a large hydrogen capacity and good desorbing properties, was found, which is a new structure on a multiphase alloy.

Journal ArticleDOI
TL;DR: The first stage of hardening in Al-Cu-Mg alloys has generally been attributed to the formation of Guinier-Preston zones comprised of copper and magnesium atoms as discussed by the authors.

Journal ArticleDOI
TL;DR: In this article, microstructural evolution in a range of laser surface treated aluminium alloys including LSM of Al-Cu, Al-Si, Al−Zn, Al•Fe and Altransitional element alloy systems; LSA of Al−Ni, Al·Cr and Al•Mo.
Abstract: Laser surface treatment techniques, including laser surface melting (LSM) and laser surface alloying (LSA), have been the subject of considerable interest as a means of enhancing the corrosion performance of aluminium and its alloys. Microstructural modification together with the incorporation of non-equilibrium concentrations of alloying elements resulting from relatively rapid rates of cooling compared with conventional surface treatment techniques provide the basis for property enhancement. This paper considers microstructural evolution in a range of laser surface treated aluminium alloys including LSM of Al–Cu, Al–Si, Al–Zn, Al–Fe and Al–transitional element alloy systems; LSA of Al–Ni, Al–Cr and Al–Mo. Where reported, corrosion and other property determination in these systems is discussed. It is shown that surface alloys with unique microstructural and compositional characteristics have been produced by these techniques and that in many cases promising improvements in hardness and critical pitting potential compared with conventional alloys have been reported.

Journal ArticleDOI
TL;DR: In this article, low-density xerogel Pd-Ag/SiO2 catalysts were prepared by a cogelation of tetraethoxysilane with organically substituted alkoxides capable of forming chelates with palladium and silver ions.

Journal ArticleDOI
TL;DR: A mathematical model has been developed to simulate the plasma nitriding process of low alloy steels, considering the simultaneous diffusion of nitrogen in ferrite, precipitation of fine scale alloy nitrides in the diffusion zone and development of γ′-Fe4N iron nitride layer on the surface.
Abstract: A mathematical model has been developed to simulate the plasma nitriding process of low alloy steels, considering the simultaneous diffusion of nitrogen in ferrite, precipitation of fine scale alloy nitrides in the diffusion zone and development of γ′-Fe4N iron nitride layer on the surface. The present paper discusses various reactions occurring during the plasma nitriding process, mathematical formulations for various reactions to form the complete model of plasma nitriding, and a numerical solution to solve the model. Computation details and results for model Cr and Ti bearing steels and commercial steels En40B, En19 and Nitraps are also presented in the paper. It is shown that the model can predict the distribution of nitrogen in solution and in the form of alloy nitride precipitates, the iron nitride layer thickness developed during plasma nitriding, the incubation time for the formation of iron nitride layer and the nitride precipitation behaviour of various alloying elements in the steel. Application of the model to plasma nitriding of commercial low alloy steels demonstrated that the model describes the nitriding response of the steels to a quite satisfactory accuracy.

Journal ArticleDOI
TL;DR: In this paper, the electrochemical oxidation of hydrogen in the presence of carbon monoxide (0.05−2%) on a well-characterized Pt75Mo25 alloy surface was examined using the rotating disk electrode technique in 0.5 M H2SO4 at 333 K.
Abstract: The electrochemical oxidation of hydrogen in the presence of carbon monoxide (0.05−2%) on a well-characterized Pt75Mo25 alloy surface was examined using the rotating disk electrode technique in 0.5 M H2SO4 at 333 K. The surface composition of this alloy determined by low-energy ion scattering after sputter cleaning and annealing in UHV was essentially the same as the bulk. The shapes of the polarization curves are qualitatively similar to those for the Pt50Ru50 alloy examined previously: a high Tafel-slope (ca. 0.5 V/dec) region at low overpotential followed by a transition to a highly actively state where the current approaches the diffusion-limiting current; the potential where the transition to the active state occurs decreases with decreasing CO concentration, and the current in the low-overpotential region is roughly inverse half-order in the CO partial pressure. The magnitude of the current in the low-overpotential region on the Pt75Mo25 alloy is nearly the same as on the Pt50Ru50 alloy, but the po...

Journal ArticleDOI
TL;DR: In this paper, the properties of the alloys Mg-x at.%Ni (x = 33, 38, 43 and 50) with different nanometer-scale structures were successively synthesized by mechanical grinding of Mg2Ni mixed with various amounts of additional Ni, and the relations between their structural and hydriding properties were investigated in detail.

Journal ArticleDOI
01 Nov 1997-Wear
TL;DR: In this paper, the wear behavior of the 6061 Al alloy reinforced with 20 vol. % Al2O3 particles dry sliding against a tool steel counterface was studied as a function of load and with reference to different values of the matrix hardness, obtained by submitting the extruded composite to thermal and forging treatments.

Journal ArticleDOI
TL;DR: In this paper, phase equilibria were used to design Pb-free solder alloys which are drop-in replacements for 63Sn 37Pb (compositions are all in weight percent, otherwise specified), thermodynamic studies on the Sn Bi In Zn quaternary system were carried out in terms of phase equilibrium.

Journal ArticleDOI
TL;DR: In this article, a quasi-Bragg peak was obtained for surfaces of elemental Ga and a Ga-In alloy at large wave vectors qz;2.3•2.5 A 21.
Abstract: Surface-induced atomic layering at the liquid/vapor interface in liquid metals has been observed using x-ray reflectivity on sputtered clean surfaces under ultrahigh vacuum conditions. A well-defined quasi-Bragg peak is obtained for surfaces of elemental Ga and a Ga-In alloy at large wave vectors qz;2.3‐2.5 A 21 . These results are an unambiguous indication of atomic layering with an interlayer spacing d;2p/qz52.5‐2.7 A. For liquid Ga, the amplitude of the electron-density oscillations, which is significantly underestimated by existing theory and molecular simulation, decays with a characteristic length of 6 A, which is twice that of Hg. Results on the alloy show a clear enrichment of indium at the topmost surface layer, consistent with the Gibbs adsorption rule. The enrichment consists of a single monolayer, with subsequent layers at the bulk eutectic composition. In order to suppress mechanically excited surface waves, the measurements were performed on thin liquid metal films (,0.5 mm deep!, which leads to a macroscopically curved surface due to the large surface tensions in liquid metals. The experimental challenges posed by measurements on curved surfaces and the techniques that were developed are discussed in detail. @S0163-1829~97!01324-6#

Journal ArticleDOI
TL;DR: In this paper, the strength development in the mushy-zone during solidification of two commercial Al Si alloys, AlSi7Mg and AlSi11Mg, an AlCu4 alloy and an AlMg5 alloy with a vane method was analyzed.

Journal ArticleDOI
TL;DR: In this article, the properties of Zn-Ni alloying with Fe group metals have been investigated, and the results have been used to explain the observed differences in their corrosion behavior in aerated chloride solutions and in neutral salt spray tests.
Abstract: The nature of electrodeposited zinc coating corrosion inhibition by alloying with Fe group metals is not fully understood, because it depends on several factors including the microstructure. The crystallographic texture and lattice cell parameters were determined for nonchromated Zn, Zn-Co, Zn-Fe and Zn-Ni coatings, deposited from alkaline baths, and the results have been used to explain the observed differences in their corrosion behaviour in aerated chloride solutions and in neutral salt spray tests. The presence of Ni or Co in the zinc matrix increases the Zn coating corrosion resistance, while Fe has no effect. It has been suggested that the lower Zn-Ni alloy corrosion rate is due to the predominant presence in this layer of crystallographic planes with a higher packing density. The lower Zn-Co alloy corrosion rate compared with that of Zn and Zn-Fe has been associated with the lower values of its lattice cell parameter c/a (axial ratio).