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Showing papers on "Nickel published in 1970"


Book
01 Oct 1970
TL;DR: Theory of yield point phenomena and their theoretical background can be found in this paper, where the effects of tensile machine and specimen stiffness on yield point effects are discussed.
Abstract: 1 Yield Point Phenomena and their Theoretical Background.- The effects of tensile machine and specimen stiffness.- Types of yield point effects.- The upper yield point-experimental.- The upper yield point-theoretical.- The lower yield point.- Strain ageing.- Pseudo yield points.- 2 Iron and its Alloys.- Effects of carbon, nitrogen and other elements.- Quench ageing.- Yielding behaviour.- Strainageing kinetics.- Effects of radiation damage-Single crystals.- Steels.- 3 The Group Va and VIa Metals.- Vanadium.- Chromium.- Niobium.- Molybdenum.- Tantalum.- Tungsten-Alloys of these metals.- Discussion.- 4 Hydrogen in Metals.- Hydrogen embrittlement.- Solubility of hydrogen in metals.- Mild steel.- Group Va and VIa metals.- Nickel.- Palladium.- Titanium and zirconium.- 5 Aluminium and its Alloys.- The unloading yield point effect.- 'Commercially pure' aluminium.- Aluminium-copper alloys - Aluminium-magnesium alloys.- Other aluminium alloys.- Theories of yield points in aluminium alloys.- 6 Other Face-Centred Cubic Metals and Alloys.- Copper and its dilute alloys.- Brass.- Silver and its alloys.- Nickel and its alloys.- Thorium.- Ordered alloys.- 7 Miscellaneous Materials.- Whiskers.- Ionic crystals.- Semiconducting materials.- Hexagonal metals and alloys.- 8 Discussion.

440 citations


Journal ArticleDOI
TL;DR: The structure of noncrystalline electrodeposited Ni-P alloys, 73.8-81.4 at.% Ni, has been investigated by x-ray scattering and by physical density measurements as discussed by the authors.
Abstract: The structure of noncrystalline electrodeposited Ni–P alloys, 73.8–81.4 at.% Ni, has been investigated by x‐ray scattering and by physical density measurements. The x‐ray interference functions, I(k), are qualitatively inconsistent with those calculated for fcc‐, hcp‐, and Ni3P‐type crystallites. Calculated radial distribution functions RDF(r) indicate that the alloys have a better defined short‐range order than that observed in liquid noble metals above their melting points. The observed I(k) are very similar to the I(k) calculated by Dixmier, Doi, and Guinier [in Physics of Noncrystalline Solids, J. A. Prins, Ed. (North‐Holland Publ. Co., Amsterdam, 1965), p. 67] from their model. However, the parameters needed to fit the experimental results are inconsistent with the atomic sizes expected for nickel and phosphorus. The noncrystalline alloys are between 0.6% and 1.4% less dense than the corresponding mixtures of fcc Ni and Ni3P, both of which are essentially close packed. A grain boundary density defici...

273 citations


Journal ArticleDOI
01 Jun 1970
TL;DR: In this article, the formation of new nickel oxide upon boundaries of columnar grains where nickel diffusing through the oxide crystals, meets oxygen, diffusing along grain boundaries is identified as the primary cause of this stress.
Abstract: The oxidation of nickel near 1000°C is accompanied by the generation of stresses parallel with the metal-oxide interface and of magnitude (~1500 psi) sufficient to elongate nickel rod, increase sheet area, and sharpen the angle of bend of ells and helices. A primary cause of this stress is identified with the formation of layers of new nickel oxide upon boundaries of columnar grains where nickel, diffusing through the oxide crystals, meets oxygen, diffusing along grain boundaries. Classical parabolic growth of the scale gives way to a slower quasilinear rate when the major site of new oxide formation is abruptly shifted to a system of grain boundaries lying close to the metal surface and created by recrystallization of the oxide under the influence of stress and high temperature. Another source of stress in the scale arises from the constantly changing area of the metal-oxide interface when oxidation is occurring upon curved metal surfaces. This stress reinforces that generated by deposition of material at oxide grain boundaries when the surface is convex and opposes it when the surface is concave.

251 citations


Patent
02 Jul 1970
TL;DR: An alloy capable of having the property of heat recoverability imparted to its components is defined in this article, comprising 49.1 to 50.2 atomic percent of titanium, 2.5 to 4.7 atomic percent iron and the remainder nickel.
Abstract: An alloy capable of having the property of heat recoverability imparted thereto comprising 49.1 to 50.2 atomic percent of titanium, 2.1 to 4.7 atomic percent of iron and the remainder nickel.

232 citations


Journal ArticleDOI
01 Jul 1970
TL;DR: In this paper, the Na2SO4-induced accelerated oxidation of nickel has been studied at 1000°C and it has been found that low oxygen activities in the Na 2SO4, which are produced by the formation of NiO, cause the sulfur activity of Na 2 SO4 to be increased.
Abstract: The Na2SO4-induced accelerated oxidation of nickel has been studied at 1000°C. It has been found that low oxygen activities in the Na2SO4, which are produced by the formation of NiO, cause the sulfur activity of the Na2SO4 to be increased. Nickel and sulfur from the Na2SO4 combine to form nickel sulfide and the oxide ion activity of the Na2SO4 is increased. The accelerated oxidation of nickel occurs because oxide ions react with NiO to form a nonprotective oxide scale. The accelerated oxidation of nickel is not self-sustaining since oxide ions are not produced when conditions in the Na2SO4 are no longer favorable for the formation of nickel sulfide.

226 citations


Journal ArticleDOI
TL;DR: In this paper, the lattice parameters of rare-earth nickel alloys have been determined for R = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er and Y.
Abstract: Various rare-earth nickel alloys with 70–80 at.% Ni have been studied by X-ray diffraction and metallography. The lattice parameters of compounds of the type RNi3 and R2Ni7 have been determined for R = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er and Y. A structure determination is given for La2Ni7 and Sm2Ni7. Some of the compounds R2Ni7 have been observed to have two modifications. Indications have been obtained that the transformation between these two modifications is of the martensitic type. It is shown that the crystal structure of the R2Ni7 compounds is size-dependent.

141 citations



Journal ArticleDOI
TL;DR: In this article, the adsorption of cobalt, copper, and nickel from solution by a number of synthetic manganese dioxides has been studied, and compared with the release of ions during the reaction.
Abstract: The adsorption of cobalt, copper, and nickel from solution by a number of synthetic manganese dioxides has been studied, and compared with the release of ions during the reaction. It was found that the initial rapid uptake of all three ions was followed by a period of slow uptake which continued for the duration of the experiment. During the slow phase of the reactions the uptake of cobalt was greater than that of copper or nickel, and cobalt released more manganese into solution. It is suggested that cobalt is able to replace Mn3+ in the crystal lattice, and this theory is supported by arguments based on crystal field theory.

133 citations


Journal ArticleDOI
TL;DR: In this article, a model based on a reversible charge transfer step with a rate-controlling diffusion process was used to analyze the data and found that the over-all reaction for α-nickel hydroxide was found to have a diffusion coefficient of approximately 2 × 10−9 cm2 sec−.
Abstract: The mechanism of the hydrated nickel hydroxide electrode, used in the nickel cadmium battery, is a matter of considerable controversy. Potential sweep experiments were performed on film nickel hydroxide electrodes in an effort to determine the oxidation‐reduction mechanism. The existence of more than one reduced structure was confirmed and the structure known as α‐nickel hydroxide was studied in detail. A model based on a reversible charge transfer step with a rate‐controlling diffusion process was used to analyze the data. The results were in good agreement with the model. The over‐all reaction for α‐nickel hydroxide was found to be The rate‐controlling process, which was assumed to be proton diffusion, was found to have a diffusion coefficient of approximately 2 × 10−9 cm2 sec−. Evidence for the formation of a poorly conducting layer during discharge of the electrode was found and capacity loss was attributed to this.

133 citations





Journal ArticleDOI
TL;DR: In this article, ultrahigh vacuum deposited Ni, Fe, W and Mo films were used to determine molecular oxygen adsorption efficiencies, and the results showed that Ni and Fe showed the best performance.

Journal ArticleDOI
TL;DR: In this article, the synthesis, reactions, and structures associated with the'sandwich-bonded bispi-(3)-1,2-dicarbollyl) complexes of nickel and palladium, (M(n+)(1, 2-B9C2H11)2(n-4)(M=Ni,Pd), and their carbon-substituted derivatives are discussed.
Abstract: : The synthesis, reactions, and structures associated with the 'sandwich'-bonded bis(pi-(3)-1,2-dicarbollyl) complexes of nickel and palladium, (M(n+)(1,2-B9C2H11)2(n-4)(M=Ni,Pd), and their carbon-substituted derivatives are discussed. The nickel and palladium bis(dicarbollyl) systems each contain species with the metal atoms in the formal +2 (d8, two unpaired electrons for nickel, diamagnetic for palladium), +3 (d7, one unpaired electron), and +4 (d6, diamagnetic) oxidation states. X-ray diffraction studies coupled with magnetic, spectral, and electrochemical data were obtained for structural information. The uncharged (pi-(3)-1,2-B9C2H11)2M(IV) derivatives are Lewis acids which form addition compounds with a variety of 'soft' Lewis bases, e.g., halide ions, thiocyanate ion, naphthalene, etc. The C, C'-dimethyl-substituted nickel and palladium systems, M(1,2-B9H9C2(CH3)2)2, exhibit facile thermal ligand rearrangement reactions leading to three isomeric series of complexes. In these isomerization reactions, a ligand carbon atom in the icosahedral surface was found to migrate away from the metal atom while remaining adjacent to the carbon atom in the open pentagonal face of the ligand. Similar rearrangements occur in the unsubstituted Ni(1,2-B9C2H11)2 complex at 360-400C in the vapor phase. Cyclic voltammetry, optical resolution studies, kinetic and nmr data and their roles in the structure elucidation of these complexes are presented. (Author)


Journal ArticleDOI
TL;DR: In this article, the Stockmayer potential and a cell approximation for describing the lateral interaction of the adsorbed molecules were used to quantify the surface equilibria and the kinetic phenomena.
Abstract: Adsorption equilibria, adsorption rates, and exchange rates of carbon monoxide have been investigated on nickel single‐crystal faces of the (110) and (100) orientation using radiotracer techniques. On the clean annealed surfaces, carbon monoxide is uniformly bound, is mobile, and occupies an area of 9 A2 in the saturated layer. The surface equilibria and the kinetic phenomena are both quantitatively accounted for by a theory utilizing the Stockmayer potential and a cell approximation for describing the lateral interaction of the adsorbed molecules. The ion‐bombarded nonannealed surfaces are unstable and heterogeneous. The contaminated surfaces adsorb only minute amounts of carbon monoxide. The chemisorption of CO thus provides a useful criterion for the degree of cleanliness of nickel surfaces.

Journal ArticleDOI
01 Jun 1970-Carbon
TL;DR: In this paper, the structure of carbon deposited on metal substrates has been studied by thermally decomposing methane over iron, cobalt and nickel surfaces, and electron and X-ray diffraction properties of the former afforded evidence for its perfectly crystalline graphite nature.

Journal ArticleDOI
TL;DR: In this paper, the reaction mechanism of hydrogenolysis on nickel catalysts with that on platinum catalysts was compared by means of a pulse technique, using hydrogen as carrier gas for a gas Chromatographic microreactor.

Patent
15 Sep 1970
TL;DR: In this article, a coating for the gas turbine engine super-alloys is described which consists primarily of nickel, aluminum and a reactive metal such as yttrium, particularly at the composition, by weight, 14-30 percent aluminum, 0.01-0.5 percent reactive metal balance nickel.
Abstract: A coating alloy for the gas turbine engine super-alloys is described which consists primarily of nickel, aluminum and a reactive metal such as yttrium, particularly at the composition, by weight, 14-30 percent aluminum, 0.01-0.5 percent reactive metal balance nickel. A preferred embodiment also includes 15-45 weight percent chromium.

Journal ArticleDOI
TL;DR: In this paper, the authors used low energy electron diffraction to determine the conditions giving rise to the appearance and/or disappearance of adsorbed sulfur and carbon on the (110) surface of nickel and to correlate their presence with specific diffraction characteristics.

Journal ArticleDOI
TL;DR: In this article, the reversible segregation of carbon to the (100) surface of nickel has been observed at temperature through measurements of work function changes and observations of LEED patterns and Auger spectra.
Abstract: The reversible segregation of carbon to the (100) surface of nickel has been observed. The surface was studied at temperature through measurements of work function changes and observations of LEED patterns and Auger spectra. The work function increases with temperature by about 0.63 eV in the temperature range 500°–800°K. This difference is close to that obtained from reported values of the work function for Ni (100) and for carbon. Below about 650°K the diffraction pattern contains rings characteristic of a graphite layer with its basal plane parallel to the substrate. In contrast with previous LEED observations of graphite precipitation at single‐crystal surfaces, the segregation described here is reversible under temperature cycling.

Journal ArticleDOI
TL;DR: In this article, the diffusion coefficient and solubility of hydrogen in metal foils were derived by a very sensitive electrochemical method at room temperature, and in some cases with temperatures up to 80°C, for platinum, nickel, tantalum, titanium, zirconium, manganese and iron-chromium alloys.

Journal ArticleDOI
TL;DR: In this paper, a curve relating composition of synthetic pentlandite with interplanar spacing was determined experimentally as follows: d115 ǫ = 1.9407 − 0.0077x2, where x represents the iron to nickel we...
Abstract: A curve relating composition of synthetic pentlandite with interplanar spacing was determined experimentally as follows: d115 = 1.9407 – 0.0023x + 0.0077x2, where x represents the iron to nickel we...






Journal ArticleDOI
TL;DR: In this paper, the authors show evidence of long-range magnetic polarization of the palladium matrix in dilute ferromagnetic Pd(Ni) alloys, for alloys containing up to 4.7 at.% nickel.
Abstract: Neutron-scattering experiments show evidence of long-range magnetic polarization of the palladium matrix in dilute ferromagnetic Pd(Ni) alloys. The measured cross sections, for alloys containing up to 4.7 at.% nickel, are interpreted in terms of a model in which the concentration of ferromagnetically aligned giant moments is less than the concentration of nickel atoms.

Patent
John Brockway1, Neal James Kane1
08 Apr 1970
TL;DR: In this paper, a zero-valent NICKELPHOSPHITE COMPLEX is constructed by reacting a divided nICKel with a REDUCING METAL in the presence of a triary l phosphite in a SATURATED ALIPHATIC DINITRILE solver.
Abstract: THE PROCESS FOR PREPARING A ZERO VALENT NICKELPHOSPHITE COMPLEX BY REACTING A DIVALENT NICKEL COMPOUND WITH A REDUCING METAL IN THE PRESENCE OF A TRIARYL PHOSPHITE IN A SATURATED ALIPHATIC DINITRILE SOLVENT. THE REACTION MIXTURE SEPARATES INTO MULTIPLE PHASES, ONE OF WHICH CONTAINS THE DESIRED COMPLEX SUBSTANTIALLY FREE OF BY-PRODUCT AND ANOTHER PHASE CONTAINING THE BY-PRODUCT OF THE REDUCING ACTION.