Nickel alloyed with

Another type of nickel alloy with which problems of intergranular corrosion may be encountered is that based on Ni-Cr-Mo containing about 15% Cr and 15% Mo. In this type of alloy the nature of the grain boundary precipitation responsible for the phenomenon is more complex than in Ni-Cr-Fe alloys, and the precipitates that may form during unfavourable heat treatment are not confined to carbides but include at least one inter-metallic phase in addition. The phenomenon has been extensively studied in recent years . The grain boundary precipitates responsible are molybdenum-rich M C carbide and non-stoichiometric intermetallic ix... 

Gold-copper alloys exhibit exceptional resistance to corrosion, and have very low vapour pressures. Gold-nickel alloys, with similar low vapour pressure, are somewhat stronger than gold-copper at high temperatures. Both series of alloys are widely employed in vacuum systems. 

This review aims to present an account of the catalytic properties of palladium and nickel hydrides as compared with the metals themselves (or their a-phase solid solutions with hydrogen). The palladium or nickel alloys with the group lb metals, known to form /8-phase hydrides, will be included. Any attempts at commenting on the conclusions derived from experimental work by invoking the electronic structure of the systems studied will of necessity be limited by our as yet inadequate knowledge concerning the electronic structure of the singular alloys, which the hydrides undoubtedly are. 

The range of observations concerning the direct comparison of the catalytic activity of nickel and rich in nickel alloys with their respective hydride phases has been further extended on reactions of a more complicated nature such as para-ortho hydrogen conversion and ethylene hydrogenation. 

Nickel is used mostly for the production of stainless steel and other nickel alloys with high corrosion and temperature resistance. Nickel alloys and nickel platings are used in vehicles, processing machinery, armaments, tools, electrical equipment, household appliances, and coins. Nickel compounds also are used as catalysts, pigments, and in batteries. 

The Earth s core is composed of iron-nickel alloy, with an inner solid core surrounded by a molten outer core. A mismatch between the inferred density of the outer core and that predicted for iron-nickel metal at high pressure suggests that some light elements) must dilute the iron in the molten core. Some possibilities are oxygen, sulfur, silicon, and hydrogen, all elements with high cosmic abundances that can alloy with iron at very high... 

Go 0 = Co Oy + HO, and this cyanide of ccbalt, by posed to rust than pure iron, but nickel alloyed with ... 

At the present time, it is recommended that the heat-transfer surfaces of evaporators and the heat exchangers for handling hot sea water be made of 70% copper, 30% nickel alloy with 0.7% iron. This alloy has given excellent service in heat exchangers aboard ships under a wide variety of service conditions. 

V I. Dybkov. Interaction of iron-nickel alloys with liquid aluminium. Part 1. Dissolution kinetics // J.Mater.Sci.- 1993.- V.28, No.23.- P.6371-6380. 

Nickel alloyed with iron is known as Invar, Pernifer 36 and Magnifer and their composition is given in Table 4.35. The alloys have moderately good corrosion resistance to a variety of industrial environments. Alloy with 80% nickel, iron and molybdenum is used as inductive components in transformers, circuit breakers,... 

Inconel (typically 76% Ni, 7% Fe, 15% Cr) is used primarily for acid resistance at high temperatures. It maintains its strength at elevated temperature and is resistant to furnace gases, if sulfur free. It is not suitable for use in sulfidizing environments. Nickel alloys with higher chromium content such as Incoloy 800 (21% Cr) and RA-33 (25% Cr) have better oxidation resistance at higher temperatures. 

A special type of catalyst which is typified by Raney Nickel is prepared by leaching out one component from a binary alloy leaving a skeletal structure of the desired catalyst. Raney Nickel itself is made by leaching out aluminium from an aluminium-nickel alloy with sodium hydroxide. Cobalt and iron catalysts have also been prepared in this manner. 

Copper-Nickel. - Copper-nickel alloys with macroscopic particles equilibrated above 600 K exist as a continuous series of solid solutions, whereas below this temperature a two-phase system with the Cu-rich phase enveloping a... 

According to the results of the proposed investigations all above mentioned disadvantages are excluded and coatings with predetermined physical-chemical properties are obtained, in particular, on the basis of nickel alloys with different metalloids and metals (1-6,13,18,29-31). 

For a well designed membrane module of reasonably large scale, the initial cost should be dominated by the cost of the palladium content of the thin metal membrane (assuming a palladium alloy comprises the permselective layer). The module itself will be made of steel, most likely a nickel alloy, with or without significant chromium addition. The cost of the steel and the assembly labor should not exceed the cost of the palladium alloy membrane. 

The current collector is made of a material that resists the corrosive action of sulfuric acid, which may contact the collector in the event of a discontinuity in the membrane, such as a pinhole or crack, formed during fabrication, handling, or operation. Suitable materials capable of operating at 60 - 70 °C are nickel alloys. With optimized assemblies (DAP, De Nora Permelec, Milan, Italy), overall anodic overvoltages of 0.1-0.2 V at 3000 A/m are obtained. 

Nickel alloys with more than 15% Cr show good oxidation properties, which are due largely to the presence of an outer CrjOj layer. The adhesive strength of oxide films can also be greatly improved by small additions (approximately 0.1%) of cerium, lanthanum, and calcium (Ni-Cr... 

Porous metallic gas diffusion electrodes are used in these fuel cells. The anode consists of a nickel alloy with 2% of chromium. Chromium that is added prevents recrystallization and sintering of the porous nickel though it works as an electrode. This action is based on chromium forming a thin layer of chromium oxide at the nickel grain boundaries, which interferes with the surface diffusion of the nickel atoms. 

TABLE 11.2. Oxidation of Nickel Alloyed with Chromium, 1000°C, 1 atm O2... 

There is a vast literature on the compatibility of nickel alloys with molten fluorides. Because there are important trade-offs between strength, salt corrosion resistance, and air oxidation resistance, this subject is treated in Sect. 5, which discusses structural materials. 

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