Nickel aluminide

From Wikipedia, the free encyclopedia

Nickel aluminide (Ni3Al) is an intermetallic material with properties similar to both a ceramic and a metal.

An intermetallic compound can be defined as an ordered alloy phase formed between two metallic elements, where an alloy phase is ordered if two or more sublattices are required to describe its atomic structure. The ordered structure exhibits superior elevated-temperature properties because of the long-range ordered super-lattice, which reduces dislocation mobility and diffusion processes at elevated temperatures[1].

Also known as IC-221M, this alloy is made up of nickel combined with several other metals including aluminium, chromium, molybdenum, zirconium and boron. Adding boron increases the ductility of the alloy. As well, it increases the hardness.

This alloy is extremely strong for its weight, five times stronger than stainless steel. Unlike most alloys, IC-221M increases in strength from room temperature up to 800C.

Image:IC-221M_temp_graph.png

The alloy is very resistant to heat and corrosion, and finds use in heat-treating furnaces and other applications where its longer lifespan and reduced corrosion give it an advantage over stainless steel. [2]

Nickel Aluminide is unique in that it has very high thermal conductivity combined with high strength at high temperature. These properties, combined with its high strength and low density, make it ideal for special applications like coating blades in gas turbines and jet engines.

In 2005, materials scientists Dale E. Wittmer and Peter Filip at the University of Southern Illinois Carbondale, claim to have discovered the worlds most abrasion resistant material by embedding diamonds in a matrix of Nickel aluminide[3].

[edit] Properties

Density = 7.26 g/cm^3

Yield Strength Room Temp = 855 mPa

Hardness = HRC 12

[edit] References

  1. ^ Vinod K. Sikka, INTERMETALLIC-BASED HIGH-TEMPERATURE MATERIALS, Metals and Ceramics Division, Oak Ridge National Laboratory, U.S. Department of Energy, March 1999
  2. ^ Crawford, Gerald (April 2003). Exotic Alloy Finds Niche (HTML). Nickel magazine. Retrieved on 2006-12-19.
  3. ^ Scientists Develop Nickel Aluminide Composite Material that Can Cut Through Cast Iron and Granite
 This material-related article is a stub. You can help Wikipedia by expanding it.
 This chemistry article is a stub. You can help Wikipedia by expanding it.