52 



HANDBOOK OF MECHANICAL DESIGN 

 COMPOSITION AND PROPERTIES OF IRON-NICKEL-CHROMIUM ALLOYS 



Castings from the above alloys have elongation and reduction in area from 5 to 20 per cent, much less than for the 'abricated forms. 



0.08 



0.25 



0.03 



Nil 



5.00 



35.000 

 65.000 



75.000 

 100,000 



35 

 25 



70 

 55 



90 

 50 



160 

 210 



85-B 

 95-B 



B-2 



0.15 



0.43 



0.03 



Tr 



36.10 



30,000 

 45,000 



70,000 

 90,000 



35 

 25 



65 

 55 



110 

 60 



160 

 170 



85-B 

 85-B 



B-1 material, resistant to mild forms of corrosion, was extensively used for turbine blades; has been superseded by the low-carbon, 12 per 

 cent chromium A-1 type. 



High silicon, copper, or molybdenum are often found in the C-group. Titanium, vanadium, and columbium are often added to retard or 

 control carbide precipitation. 



D-l type is obtainable in nearly all forms including seamless pierced and drau-n tubes. D-2 type with modifications is available in various 

 forms. Most of this material is used for heat resistance. For turbine blading, a lower chromium content is used for temperatures above 

 800°F. D-3 type is obtainable only in restricted forms. Modifications of this type are obtainable in certain forgings although it is difficult to 

 fabricate. With the addition of 15 to 20 per cent molybdenum, this material becomes immune to hydrochloric and sulphuric acids. 



Note 1: In columns headed yield point and ultimate stress, the first figure refers to the annealed condition; the second figure is for cold- 

 worked or hardened material. Differences between these figures and other published data are accounted for by modifications of analysis or 

 by variations in heat-treatment or work hardening during fabrication. 



Note 2: The first figure is the ultimate stress obtained after 1 hr. at temperature; the second figure is considered by the author to be a 

 conservative design stress for use at these temperatures. These working stresses are based on experience and have been used satisfactorily. 

 But they should not be confused vnih creep strengths. 



