Evaporation Of Alloys Research Articles

924. Single-source evaporation of gadolinium-cobalt alloys: R C Taylor,J Vac Sci Technol, 11 (6), 1974, 1148–1150

924. Single-source evaporation of gadolinium-cobalt alloys: R C Taylor,J Vac Sci Technol, 11 (6), 1974, 1148–1150

Single-source evaporation of gadolinium-cobalt alloys

A study was made of the feasibility of using single-source electron gun evaporation for the preparation of amorphous Gd-Co alloy films. The sources used covered the compositional range from Gd0.20Co0.80 to Gd0.60Co0.40. The films deposited from each source were analyzed and the results compared with those expected for ideal alloys based on calculations using Raoult's law and Langmuir's equation. It was found that real alloys gave films with compositional gradients more than twice as severe as would be expected from ideal alloy calculations. In order to obtain films with compositional variations of one percent or less, the evaporation must consume no more than one percent of the source material.

Abstract: Effect of pool temperature gradients on the composition of electron-beam vapor-deposited alloys

The common requirement of a water-cooled hearth for continuous electron-beam evaporation of alloys with a rod-fed source introduces a temperature gradient in the evaporating surface. A spatial heterogeneity of alloying constituents can be shown to result from evaporation in this gradient. Application of thermodynamic considerations to the equilibrium evaporation at constant rate from an alloy-rod-fed electron-beam vapor-deposition source provides an explanation of the spatial heterogeneity of alloy constituents in the vapor cloud. Consideration of these effects offers some direction for improved electron-beam gun/hearth design for utilization in vapor-deposition processing of complex alloys.

980. Regularities of formation of structure and properties of films prepared by vacuum evaporation of alloys based on copper: A M Korolkov et al,FizObrabMater, No 3, 1973, 58–61 ( in Russian)

A study of the coprecipitation of thallium with As2S3, SnS2, MoS3, Re2S7, PtS2, PdS, Ru2S3, Rh2S3, Ir2S3 and In2S3, and of indium with CuS and Ag2S by physicochemical analysis has shown that the process results from formation of the following compounds: TlAsS2, TlSnS2, TlMoS2, TlReS4, TlPtS3, TlPd2S3, TIRu2S3, TIRh2S4, Tl3Ir3S, TlIn2S3, CuInS2 and AgInS2. A type of coprecipitation diagram characteristic for the case of the formation of chemical compounds has been established and the fields on it, corresponding to phases of definite composition, have been delimited. The formation in the coprecipitation of microdisperse systems of “colloidal” sold solutions of one sulphide in another has been shown.Eine Untersuchung der Mitfällung von Thallium mit As2,S3, SnS2, MoS3, Re2S7, Pt2, PdS, Ru2,S3, Rh2,S3, Ir2S3 und In2S3 und von Indium mit CuS und Ag2S mit physikochemischen Methoden zeigte, daß die Mitfällung auf der Bildung folgender Verbindungen beruht: TlAsS2, TlSnS2, TlMoS2, TlReS4, TlPtS3, TlPd2S3 TlRu2S6, TlRh2S4, Tl4Ir3S, TlIn2S3, CuInS2 und AgInS2. Eine für die Bildung von Verbindungen charakteristische Art von Mitfällungsdiagramm wurde aufgestellt und darauf die Phasen bestimmter Zusammensetzung entsprechenden Bereiche abgegrenzt. Es wurde gezeigt, daß sich bei der Mitfällung mikrodisperser Systeme “kolloide” feste Lösungen eines Sulfids im andern bilden.Une étude de la coprécipitation du thallium avec As2S3, SnS2, MoS3, Re2S7 PtS2, PdS, Ru2S3, Rh2S3, Ir2S3 et In2S3, et de l'indium avec CuS et Ag2S au moyen de l'analyse physicochimique a montré que le phénomène est dûá la formation descomposés suivants: TlAsS2, TlSnS2, TlMoS2, TlReS4, TlPtS3, TlPd2S3, TlRu2S6, TlRh2S4, Tl3Ir3S, TlIn2S3, CuInS2 et AgInS2. On a établi un type de diagramme de coprécipitation caractéristique, pour le cas où il y a formation de composés chimiques, et on y a délimité les domaines correspondant aux phases de composition définie. On a montréqu'il se forme, lors de la coprècipitation, des systémes microdisperses de solutions solides “colloïdales” d'un sulfure dans l'autre.

Laws governing the development of structure in the films formed by the vacuum evaporation of certain pure metals and fractionating copper alloys

The phase composition of the films produced by the vacuum evaporation of several pure metals and fractionating copper-base alloys, with deposition on a sodium chloride (100) cleavage, is studied by transmission electron microscopy and electron diffraction. The phase compositions of films deposited at different stages in the evaporation of alloys containing elements with severely differing vapor tensions differ considerably. Certain conclusions are drawn regarding the distribution of the alloying elements over the thickness of the films so formed during the complete evaporation of the alloy samples.

Structure of chromium-rich Cr-Ni, Cr-Fe, Cr-Co, and Cr-Ni-Fe alloy particles made by evaporation in argon

Structural analyses were performed on alloy particles of chromium-rich Cr-Ni, Cr-Fe, Cr-Co, and Cr-Ni-Fe systems. Fine alloy particles (100 to 1000A in diameter) were prepared by evaporation of parent alloys in argon at 20 torr. In addition, alloy structures of bulk specimens of the Cr-Ni system were investigated using X-ray diffraction techniques to confirm the results obtained from the particulate alloys. In these binary systems, δ phase with W3O structure (A-15) and a phase withβ-uranium structure (D 8 ) were identified in addition to the α (bcc) and γ (fcc) terminal solid solutions. The compositional ranges for the σ phase in the Cr-Ni, Cr-Fe, and Cr-Co systems are from low chromium to 68, 63.4, and 62.1 wt pct Cr, respectively. The δ phase exists in the range from pure chromium to 68, 58, and 54 wt pct Cr in the respective Cr-Ni, Cr-Fe, and Cr-Co alloy systems. Similarly, in the Cr-Ni-Fe system, it was found that δ phase occurs in the chromium corner while σ phase exists in the region bridging the two binary σ phases of the Cr-Ni and Cr-Fe systems. Possible modification of phase diagrams of these systems is discussed in view of these results.

1535. Investigation of the process of thermal evaporation of multicomponent alloys in vacuum: V A Rossinskiy et al, Elektron Tekh Tekhnol Organ Proiz, 2, 1971, 71–75 ( in Russian)

1535. Investigation of the process of thermal evaporation of multicomponent alloys in vacuum: V A Rossinskiy et al, Elektron Tekh Tekhnol Organ Proiz, 2, 1971, 71–75 ( in Russian)

1209. Kinetics and thermodynamics in continuous electron-beam evaporation of binary alloys: T Santala and C M Adams, J Vac Sci Technol, 7 (6), Nov/Dec 1970, S22– S29

1209. Kinetics and thermodynamics in continuous electron-beam evaporation of binary alloys: T Santala and C M Adams, J Vac Sci Technol, 7 (6), Nov/Dec 1970, S22– S29

Theory of Steady-State Evaporation of Alloys

The theory of steady-state evaporation, which produces a vapor having the same composition as the alloy to be evaporated, is given. Equations are derived showing the composition of the evaporant, which is physically separated from the alloy feed, during the approach to steady state. The general case of N components is treated, and closed solutions are given for various special cases involving two, three, and N components with different vapor pressures. Illustrative numerical examples are given.

Kinetics and Thermodynamics in Continuous Electron-Beam Evaporation of Binary Alloys

Continuous electron-beam evaporation of binary alloys was studied. Silver-copper wires with 5, 10, 20, and 30 at.% of silver were fed into an evaporation source which was heated by an electron beam. Beam powers up to 4.5 kW were used and evaporation temperatures from 1625–1960 K were obtained. Methods were developed to study mass and composition distribution of the vapor flux, the transient period, and the steady-state conditions. Prediction of the transient and the steady-state relationships among the compositions of the feed wire, the evaporant bath, and the vapor deposit, based on (a) published thermodynamic properties of silver-copper alloys, and (b) the assumption that the Langmuir equation correctly relates the evaporation rate of a particular component from solution to the equilibrium partial pressure of that component, agrees closely with experimental results. This means that transport within the liquid phase by diffusion or convection is not a significant rate-controlling factor.

Theory and Practice of Steady-State Evaporation of Alloys

InSb films have been grown by steady-state evaporation, a technique that produces a vapor with the same composition as the starting liquid. Films deposited on glass substrates at room temperature typically have Hall coefficients of 10–50 cm3/C, resistivities of 0.05 and 0.5 Ω cm, and Hall mobilities of the order of 200 cm2/V sec. X-Ray fluorescence analyses of films deposited on thin plastic substrates at room temperature indicate random departure from stoichiometry of as much as 1%. Comments are made on source design and conditions that may cause deviations from stoichiometry. The theory of steady-state evaporation is briefly discussed.

Investigation of magnesium and MA 2-1 alloy evaporation in chambers with cryogenic surfaces. (USSR): Yu M Gushchina et al, Izv VUZ Fiz,10 (9), 1967, 12–18 (in Russian)

Investigation of magnesium and MA 2-1 alloy evaporation in chambers with cryogenic surfaces. (USSR): Yu M Gushchina et al, Izv VUZ Fiz,10 (9), 1967, 12–18 (in Russian)

The field evaporation of dilute alloys

Field evaporation of a dilute alloy can be discussed in terms of the heats of solution or adsorption of the solute species and the appropriate ionisation potentials. Evaporation fields calculated for solute species can be used to predict whether the solute is preferentially retained or evaporated in the lattice. Because of their high ionisation potentials non-metallic impurities tend to be preferentially retained and may evaporate as molecular ions. Field etching may be treated as a special case of evaporation as a molecular ion in which evaporation occurs before the heat of adsorption is dissipated in the lattice. Under some conditions calculations predict preferential field etching of non-metallic impurities.

1558. Study of the laws governing the evaporation of alloys

1558. Study of the laws governing the evaporation of alloys

Investigation of oxidation and evaporation of resistance alloys in vacuum: S G Murovannaia and E N Marmer, Elektro-Termiia, 39 (5), 1964 (in Russian)

Investigation of oxidation and evaporation of resistance alloys in vacuum: S G Murovannaia and E N Marmer, Elektro-Termiia, 39 (5), 1964 (in Russian)

Investigation of oxidation and evaporation of resistance alloys in vacuum

Investigation of oxidation and evaporation of resistance alloys in vacuum

72. The direct evaporation of alloys: G Zinsmeister,Vak Technik,13(8), Dec 1964, 233–240

72. The direct evaporation of alloys: G Zinsmeister,Vak Technik,13(8), Dec 1964, 233–240

290. The evaporation of iron-chromium alloys containing 5 and 25 per cent chromium in the temperature range 900°–1080° C: L. A. Morris and W. W. Smeltzer, J. Electrochem. Soc., 110, Sept. 1963, 997–1001

290. The evaporation of iron-chromium alloys containing 5 and 25 per cent chromium in the temperature range 900°–1080° C: L. A. Morris and W. W. Smeltzer, J. Electrochem. Soc., 110, Sept. 1963, 997–1001

The Evaporation of Iron‐Chromium Alloys Containing 5 and 25 Per Cent Chromium in the Temperature Range 900°–1080°C

An investigation is reported on the evaporation and thermal etching of iron alloys containing 5 and 25% chromium in the temperature range 900°–1080°C under a vacuum of 10−6 mm Hg. Evaporation proceeded by constant rates for exposures extending several hours; the activation energies were 94.3 and 93.7 kcal/g f w for the austenitic 5% and ferritic 25% alloy, respectively. Thermal etching gave rise to both faceted and specular surfaces.

The Adhesion of Vacuum-Evaporated Metal Films

General technique for the vacuum evaporation of metals and alloys and the mechanism of formation of the evaporated film on metallic or non metallic surfaces are reviewed. Factors making for good an...