Alloys for intermediate temperature applications, methods for maufacturing thereof and articles comprising the same

Abstract

Disclosed herein is a composition comprising iron; about 18 to about 30 wt % chromium; up to about 7 wt % tungsten; up to about 1.5 wt % manganese; up to about 1 wt % aluminum; about 0.02 to about 0.1 wt % of a rare earth metal and/or yttrium; wherein the weight percents are based on the total weight of the composition. Disclosed herein too is a method comprising melting together a composition comprising iron; about 18 to about 30 wt % chromium; up to about 7 wt % tungsten; up to about 1.5 wt % manganese; up to about 1 wt % aluminum; about 0.02 to about 0.1 wt % of a rare earth metal and/or yttrium; wherein the weight percents are based on the total weight of the composition; casting the composition; and rolling the composition.

1 . A composition comprising: 
 iron;    about 18 to about 30 wt % chromium;    up to about 7 wt % tungsten;    up to about 1.5 wt % manganese;    up to about 1 wt % aluminum;    about 0.02 to about 0.1 wt % of a rare earth metal and/or yttrium; wherein the weight percents are based on the total weight of the composition.    
   
   
       2 . The composition of  claim 1 , having an area specific resistivity of about 5 to about 40 milliohm-square centimeter at 750° C., when oxidized in a sandwich configuration at 750° C. for about 1,500 hours.  
   
   
       3 . The composition of  claim 1 , having an area specific resistivity of about 20 to about 120 milliohm-square centimeter at 750° C., when oxidized in a sandwich configuration at 850° C. for about 1,500 hours.  
   
   
       4 . The composition of  claim 1 , having a coefficient of thermal expansion of greater than or equal to about 11.75 parts per million per degree centigrade.  
   
   
       5 . The composition of  claim 1 , having a coefficient of thermal expansion of about 11.75 to about 12.6 parts per million per degree centigrade.  
   
   
       6 . The composition of  claim 1 , wherein the chromium is present in an amount of about 25 wt %, based on the total weight of the composition.  
   
   
       7 . The composition of  claim 1 , wherein the rare earth metal is lanthanum.  
   
   
       8 . The composition of  claim 1 , comprising about 5 to about 7 wt % tungsten.  
   
   
       9 . The composition of  claim 1 , comprising about 0.5 to about 1.5 wt % manganese.  
   
   
       10 . The composition of  claim 1 , comprising about 0.5 to about 1 wt % aluminum.  
   
   
       11 . An article manufactured from the composition of  claim 1 .  
   
   
       12 . A method comprising: 
 melting together a composition comprising:    iron;    about 18 to about 30 wt % chromium;    up to about 7 wt % tungsten;    up to about 1.5 wt % manganese;    up to about 1 wt % aluminum;    about 0.02 to about 0.1 wt % of a rare earth metal and/or yttrium; wherein the weight percents are based on the total weight of the composition.    casting the composition; and    rolling the composition.    
   
   
       13 . The method of  claim 12 , further comprising forging the composition.  
   
   
       14 . An article manufactured by the method of  claim 12.