High-temperature Nickel-based Alloy Research Articles

Elevated temperature creep-fatigue crack propagation in nickel-base alloys and 1 Cr-Mo-V steel

The crack growth behavior of several high temperature nickel-base alloys, under cyclic and static loading, is studied and reviewed. In the oxide dispersion strengthened (ODS) MA 6000 and MA 754 alloys, the high temperature crack propagation exhibited orientation dependence under cyclic as well as under static loading. The creep crack growth (CCG) behavior of cast nickel-base IN-738 and IN-939* superalloys at 850 °C could be characterized by the stress intensity factor,K 1. In the case of the alloy IN-901 at 500 °C and 600 °C,K 1 was found to be the relevant parameter to characterize the creep crack growth behavior. The energy rate line integral,C*, may be the appropriate loading parameter to describe the creep crack growth behavior of the nickel-iron base IN-800H alloy at 800 °C. The creep crack growth data of 1 Cr-Mo-V steel, with bainitic microstructure, at 550 °C could be correlated better by C * than byK 1.

Analysis of metal alloys by second-harmonic phase-selective a.c. voltammetry

Second-harmonic phase-selective a.c. voltammetry and second-harmonic a.c. anodic stripping voltammetry are shown to be particularly suitable for simultaneous determinations of elements having very close half-wave potentials (differences of <50 mV). The technique are applied to real matrices. Samples of standard materials BCS 207/2 Gunmetal, SRM 631 SPectrographic Zinc Spelter and SRM 899 (Nickel-base High-temperature Alloy) were digested with a sulphuric acid/nitric acid mixture; after dissolution, the samples were taken up in hydrochloric acid. After adjustment to 1 mol l −1 HCl, the solutions were used directly for voltammetric measurements of Pb(II)/Sn (II), Sb(III)/Bi(III), Pb(II)/Tl(I) and In(III)/Cd(II) as appropriate. The confidence intervals of the experimental data were in agreement with the certified values for each element. Both the accuracy, expressed as percentage error, and precision, expressed as relative standard deviation, were better than 5%. The standard addition technique was found to improve the resolution of the a.c. voltammetric peaks even in the case of severe overlapping.

HAYNES ALLOY No. 263

Abstract HAYNES alloy No. 263 is a vacuum-melted and electroflux-refined high-temperature nickel-base alloy. It has good formability and weldability. It was developed by Rolls Royce. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep, and deformation. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: Ni-352. Producer or source: Haynes International Inc..

NIMONIC 86

Abstract NIMONIC alloy 86 is a nickel-base high-temperature alloy with exceptionally good cyclic oxidation resistance at 1050 C (1922 F). The alloy has good workability, ductility and weldability. It is intended principally for use in sheet form. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-351. Producer or source: Inco Alloys International Inc..

The analysis of carbide and intermetallic phase γ′ isolates in nickel alloys by means of injection method of flame atomic absorption spectrometry

The determination of the chemical composition of intermetallicγ′ phase and carbide isolates is of a great importance for estimating the properties of the high-temperature nickel-base alloys. This paper presents the examination of the application of these isolates for the chemical analysis; a modernized variant of the injection technique of flame atomic absorption is described. It is based on constructing the teflon crater manifold together with a portable capillary bearing. The precision of the determination of the given elements inγ′ phase isolates was as follows: Al 3.5–4.2%, Ti 4.1–4.6%, Mo 3.8–4.2%, Co 2.5–2.8%, W 8.6–8.8%, Nb 11.2–11.6%, Cr 3.1–3.4%, Ta 10.2–10.6%.

Effect of temperature and type of stress state on the endurance of high-temperature cast alloy ZhS3DK

In aviation gas-turbine practice there has been extensive use of high-temperature nickel-base alloy ZhS3DK as a material for gas-turbine blades. In view of the tendency towards increased operating tempertures with an increase in aircraft component life, an all-around study of its strength properties is undertaken, including resistance to cyclic loading over a wide temperature range. Results are presented for a study of the endurance of alloy ZhS3DK specimens over a wide temperature range (20-900 degrees C) with pure rotating bending and with tension-compression.

Determination of selenium in a nickel alloy by flame atomic absorption spectrometry after electrochemical preconcentration

The nickel alloy is dissolved in nitric/hydrochloric/phosphoric acid mixture, and selenium is electrodeposited onto a platinum loop at −0.4 V (vs. Ag/AgCl). Selenium is atomized from the electrode in an argon/hydrogen flame with simultaneous electrothermal heating of the loop. For the NBS standard nickel-based high-temperature alloy (SRM 899), the mean value found was 9.7 μg g −1 with a standard deviation of 0.4 μg g −1 (certified value 9.5 ± 0.1).

Thermal shock resistance of blades with protective coatings in a corrosive atmosphere

1. Diffusion impregnation of a blade surface with aluminum; titanium and aluminum; chromium, silicon, and aluminum with yttrium; cobalt, chromium, and aluminum with yttrium, reduces the corrosion rate for high-temperature heat-resistant and low-temperature heatresistant nickel-base alloys in an atmosphere with sea salt. 2. The most effective coating of those tested under thermal cycling conditions for a gas flow containing sea salt is a multicomponent coating of electron beam evaporation and deposition in a vacuum of cobalt-chromium-aluminum-yttrium. Effective blade corrosion protection may also be achieved by applying a chromium-aluminum-silicon-yttrium coating. 3. Thermal shock resistance of blades with coatings is mainly governed by the relationship of base metal and coating properties. Some coatings may reduce blade material to resist thermal fatigue. 4. The presence of sea salt in the gas stream in amounts close to operating conditions leads to high-temperature sea salt corrosion of blades, and also to a reduction in thermal cycling resistance and working capacity.

ニッケル基耐熱合金のＮａ２ＳＯ４による高温腐食に及ぼす合金元素の影響

The problem of hot corrosion of high-temperature alloys used to aircraft engines and industrial gas turbines has been known for many years. It is usually attributed largely to the presence of sodium sulfate which is formed by reaction between sodium chloride injected from marine environment and sulfur in the fuel.In this paper, the effects of alloying elements of nickel-base high-temperature alloys on the hot corrosion induced by sodium sulfate are discussed.

AISI No. 664

Abstract AISI No. 664 is a nickel-base high-temperature alloy that can be precipitation hardened because of its contents of aluminum and titanium. Vacuum melting is used in its production to provide excellent quality and reproducability. It is used for applications requiring a good combination of creep and stress-rupture properties up to about 1500 F. Typical applications are gas-turbine components, airframes and fasteners. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ni-269. Producer or source: Nickel alloy producers.

Further observations on the effect of environment on the creep/rupture behavior of a nickel-base high temperature alloy: Grain size effects

Udimet 700 monocrystals and polycrystals of varying numbers of grains per cross section were statically stressed to 172.4 MN/m 2 (25 ksi) at 1200 K (1700 °F) in air and at 10 −5 Torr. The rupture life was longer, and the minimum creep rate (MCR) was smaller, in air, for the single crystals. As the number of grains per cross section increased, the life decreased (and the MCR increased) in air, whereas the reverse occurred under vacuum. These results are rationalized in terms of the micromechanisms of flow and fracture at elevated temperature in this material.

Behavior of a nickel-base high-temperature alloy under hot-working conditions

The behavior of a Ni--Cr--Co base alloy with significant additions of Mo, Ti and Al (Ni-monic 105) under hot working conditions was studied using hot compression tests in the temperature range of 1223 to 1523/sup 0/K and strain rates between 0.38 and 64.3 s/sup -1/. The microstructure of the Nimonic 105 is complex and the matrix contains second phases in the form of Ni/sub 3/ (Ti, Al) dispersion (..gamma..'), various Cr and Ti carbides and titanium cyanonitrides inclusions. However, the results show that above the dissolution temperature of the ..gamma..' phase, the alloy behaves like a single phase nickel-base solid solution from the point of view of steady state flow stress-temperature-strain rate relationships, and the activation energies for hot working and static recrystallization. Under deformation conditions where the ..gamma..' phase is present, as in the case of creep; the activation energy is almost doubled. The hot working temperature range giving sound product is 1280 to 1450/sup 0/K at a strain rate of 0.4 s/sup -1/ and decreases to 1400 to 1480/sup 0/K at a strain rate of 65 s/sup -1/. At temperatures above the higher limit the alloy suffers intercrystalline cracks due to hot shortness and at temperatures below themore » lower limit the alloy suffers transcrystalline cracks due to excessive strain hardening.« less

A potentiometric study of the oxidation of cobalt(II) with gold(III) chloride in presence of 1,10 phenanthroline or 2,2'-bipyridine : A new titration of cobalt (II) and its application to nickel-base alloys

The redox reaction between cobalt(II) and gold(III) chloride in the presence of 1.10-phenanthroline or 2,2'-bipyridine was studied, and a titration of the cobalt(II) complex with a gold(III) chloride solution was developed. A 4-fold amount of 1,10-phenanthroline or 2,2'-bipyridine was necessary for rapid quantitative reaction; the permissible pH range was 1.5–5. The oxidation of the cobalt(II) complex proceeds rapidly at 40–50°C, and a direct potentiometric titration was possible. The following maximum errors were obtained: 3.3% for 0.2–1.0 mg Co, 2.0% for 1–5 mg Co, and 0.70% for 10–40 mg Co. The following ions did not interfere: Ni(II), Zn(II), Pb(II), Cd(II), Mn(II), Fe(II), Cr(III), Al(III), Th(IV), Se(IV), Ti(IV), U(VI), Mo(VI), SO 2- 4 and PO 3- 4. Even small quantities of silver(I), copper(II), palladium(II), mercury(II)and iron(III) interfered. The method was applied to the determination of high cobalt contents in high-temperature nickel-base alloys.

The effect of an air environment on the creep and rupture behavior of a nickel-base high temperature alloy

The behavior of wrought and cast polycrystalline Udimet 700 tested in static tension at 1200 K (1700†F) has been determined. An air environment decreases rupture life and ductility, except in very coarse-grained cast specimens, because of premature failure by stress-assisted grain boundary oxidation and cracking. In very coarse-grained cast specimens greater life and ductility are found in air than in vacuum, presumably due to the paucity of transverse grain boundaries and to some type of surface hardening effect. Wrought specimens exhibit greater grain boundary sliding, hence more cracking, shorter life, and lower ductility, than cast specimens in any environment. This is attributed to differences in grain boundary topography.

HASTELLOY ALLOY S

Abstract HASTELLOY alloy S is a nickel-base high-temperature alloy having excellent thermal stability, good high-temperature mechanical properties and excellent resistance to oxidation up to 2000 F. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ni-184. Producer or source: Stellite Division, Cabot Corporation.

UDIMET 75

Abstract UDIMET 75 is a nickel-base high-temperature alloy developed for good resistance to oxidation and scaling to 2000 F. It can be fabricated and welded readily. This datasheet provides information on composition, physical properties, elasticity, and tensile properties as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ni-171. Producer or source: Special Metals Corporation.

Creep Induced Twinning in A Γ'-Precipitation Hardened Nickel-Base Alloy

High temperature nickel-base alloys are strengthened by a high volume fraction, coherent precipitate of γ’ [Ni3 (Al,Ti)], with Ll2 structure. The mechanical properties of these alloys are dependent upon the interaction of dislocations with the ordered γ’ precipitate. A detailed diffraction contrast analysis has been made of dislocation/ γ’ particle interactions occurring during 1400oF creep of the nickel-base alloy Mar-M200.In the early stages of creep, two types of γ’ particle shearing mechanisms have been observed, Fig. 1. The interpretation of these micrographs is illustrated in Fig. 2.

Stacking faults in gamma prime Ni3(Al,Ti) precipitation hardened nickel-base alloys

Most high temperature nickel-base alloys are strengthened by a coherent, orderedγ′ precipitate of Ll2 structure. Examination of thin foils of these materials after various thermal and/or mechanical treatments has shown the presence of stacking faults in a variety of forms. Stacking faults are developed in conjunction with certain phase reactions, and during plastic deformation. The experimental evidence indicates that stacking fault energy is an important parameter determing the slip mode and strength at low and intermediate temperatures.

Sulfidation of a Complex Nickel Base Alloy-Inconel 713C

Abstract The reaction between a complex high-temperature nickel-base alloy Inconel 713 C and hydrogen sulphide diluted with air was investigated in the temperature range of 705 C to 927 C under atmospheric pressure. The sulphidation in an atmosphere of 10% hydrogen sulphide between 816 C-885 C has been found to follow a parabolic-rate law with an activation energy of about 55 kcals/mole. Metallographic studies have shown that the scale is composed of two distinct layers. X-ray and electron microprobe analyses demonstrated that the outer layer is composed mainly of Ni3S2 and that the inner layer is a mixture of unidentified sulphides with chromium and aluminum as major components. The reduced rate of corrosion appears to be the result of the formation of the inner layer of scale.

Dislocation structure of a high-temperature nickel-base alloy fatigued at several temperatures

Dislocation structure of a high-temperature nickel-base alloy fatigued at several temperatures