Alloys Used for High Temperature Service

Many components in Jet and Rocket Engines , and in Nuclear Equipment have to withstand temperatures in excess of 1100*C. This has made to develop a number of highly specialized alloys. Nickel or Cobalt forms the base metals in this range of alloys. Most of these alloys possess yield strength in excess of 70 MN / mm2. or 700 kg-f / mm2 and 250 to 370 Brinell hardness number at room temperature.

Alloys used for High Temperature and Its Composition :

1.) Nimonic 80 A :

Chromium - 21% ,Titanium -2.5 % , Aluminum - 1.2 % ,Carbon - 0.04% ,Nickel - 75.26 %

2.) Inconel 713C :

Chromium - 12% ,Titanium -0.5 % ,Tantalum - 2.0% ,Aluminum - 6% ,Carbon - 4.5 % ,Nickel - 75%

3.) Incoloy 910 :

Nickel - 42% ,Chromium -13 % ,Titanium - 2.4 % ,Carbon - 0.04 % ,Molybdenum - 6% ,Iron - 36.56%

4.) Hastelloy :

Nickel - 45% ,Chromium - 22% ,Cobalt - 1.5% ,Tungsten - 0.5% ,Carbon - 0.15% ,Molybdenum - 9%

5.) Vitallium :

Nickel - 2.5% ,Chromium - 28% ,Cobalt - 62% , Iron - 1.7% ,Carbon - 0.28% ,Molybdenum - 5.5%

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