High-strength, high-ductility noudlar iron, and transmission housing produced therefrom

Abstract

An improved nodular cast iron is intended, despite having a high strength, to be ductile, to have good machining properties and to be weldable. It contains: 4 to 6 percent of silicon and a carbon content which has been reduced by an amount corresponding to the carbon equivalent, at most 0.03 percent of phosphorus and 0.2 to 0.5 percent of nickel. A casing (1) made from the nodular cast iron is welded to a toothed part (2) made from alloyed and/or case-hardened steel.

1 . A nodular cast iron with alloyed-in silicon, comprising: 
 a) 4 to 6 percent of silicon and a carbon content which is reduced by an amount corresponding to the carbon equivalent,    b) at most 0.03 percent of phosphorus,    c) 0.2 to 0.5 percent of nickel,    d) remainder iron and inevitable impurities.    
     
     
         2 . The modular cast iron as claimed in  claim 1 , wherein the silicon content is 4.1 to 4.5 percent.  
     
     
         3 . The nodular cast iron as claimed in  claim 1 , wherein the nickel content is 0.25 to 0.35 percent.  
     
     
         4 . The nodular cast iron as claimed in  claim 1 , further including at most 0.3 percent of copper.  
     
     
         5 . A casing comprising a first part (1) of nodular cast iron as claimed in one of the preceding claims.  
     
     
         6 . The casing as claimed in  claim 5 , wherein the first part (1) is welded to a toothed part (2) made from one of alloyed steel and case-hardened steel.