K Monel 500

NICKEL ALUMINIDE

Nickel aluminide (NiAl) is available commercially in powder form in various mesh sizes from granular material to an average particle size of a few micrometers. Nickel aluminide is fairly strong at room temperature with modulus of transverse rupture values ranging from 204 to 952 MPa, depending on fabrication methods, while at 1000°C the corresponding values are approximately half the room temperature strength. Creep resistance at these temperatures is extremely poor. Thermal shock resistance is quite good.

Nickel aluminide can be formed by hot pressing or by cold pressing and sintering, but the former method produces by far the best results.

Excellent oxidation resistance and fairly good strength make this material of interest for turbine blading or other combustion chamber applications. It has impact resistance that is better than most ceramics, intermetallic compounds, and some cermets. NiAl is also resistant to attack by molten glass and red and white fuming nitric acid, which suggests possible uses in the glass-processing industry or in some high-temperature chemical processes.

A silvery-white metal, nickel (Ni), has been used in alloy form with copper since ancient times. Nickel has a specific gravity of 8.902, or a density of 8.902 g/cm3, and is magnetic up to 360°C. The metal is highly resistant to atmospheric corrosion and resists most acids, although it is attacked by oxidizing acids, such as nitric. Its principal use is as an alloying element to stainless steels, alloy steels, and non-ferrous metals. It is also used for electroplating.

There are several commercial high-purity nickels, containing at least 99% of the metal plus trace amounts of combined cobalt, and small amounts of other elements, such as carbon, copper, iron, manganese, silicon, and sulfur. They find use in electronic and aerospace applications, chemical- and food-processing equipment, and for anodes and cathodes, caustic evaporators, and heat shields. Nickel 200, also known as commercially pure nickel, may contain as much as 0.15% carbon, 0.25% copper, 0.40% iron, 0.35% manganese, 0.35% silicon, and 0.01% sulfur. It is especially resistant to caustics, high-temperature halogens and hydrogen halides, and salts, but not to oxidizing halides or ammonium hydroxide. Because it is susceptible to high-temperature embrittlement by carbon precipitation, however, it is restricted to a maximum service temperature of 316°C. Nickel 201, its low-carbon (0.02% maximum) counterpart, can be used at higher temperatures. The cast grade, designated CZ-100, is recommended for use at temperatures above 316°C.

British corrosion journal, a publication of the Metals Society

Metallic materials specification handbook

Handbook of electron tube and vacuum techniques

Design for manufacturability handbook

Nickel, cobalt, and their alloys