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HANDBOOK OF MECHANICAL DESIGN 



EFFECT OF NICKEL AND CHROMIUM ON CAST IRON 



Addition of Nickel. 



1. Increases strength and elasticity when composition of the iron is adjusted, 

 especially the sUicon content. 



2. Refines the grain and reduces porosity. 



3. Increases hardness. 



4. Eliminates hard spots and thus improves machinability when nickel additions 

 amount to K to 4 per cent depending upon the sUicon content and section 

 thickness. 



5. Decreases the amount of sihcon needed to keep castings gray and machinable. 



6. Increases wearing quahties. 



7. Improves impact resistance. 



8. Improves heat and corrosion resistance. 



9. Raises electrical resistance. 

 Addition of Chromium. 



1. Improves tensile strength. 



2. Refines the grain. 



3. Increases hardness. Produces hard spots when used alone or in excessive 

 amounts. 



4. Increases chilling power, depth of chill, and the combined carbon. 



5. Increases heat resistance. 



6. Increases wear resistance. 



7. Increases corrosion resistance. 



8. Decreases machinability. 

 Addition of Nickel and Chromium Together. 



1. By using two or three parts of nickel to one of chromium, the chilling action of 

 chromium is restrained and the beneficial effects of chromium are retained. 



2. Increases strength and hardness. Amounts needed to obtain maximum 

 machining qualities, and also hardness and strength, in castings of various 

 section thickness are shown in the accompanying table. 



Applications for Nickel and Nickel -chromium Cast Iron. 



Cylinders, cams, gears, hardware, bushings, machine frames, liners, and plates. 



NICKEL AND CHROMIUM IN CAST IRON FOR MAXIMUM MACHINABILITY 



