Alloy and method for producing alloy

Abstract

To provide an alloy which can suppress minute temporal deformation of a Super Invar alloy as much as possible, and a method for producing the alloy. The alloy of the present invention includes iron, nickel, and cobalt, which are the basic components of a Super Invar alloy, and is characterized in that an amount of a fraction which has not carbidized in carbon contained in the alloy is 0.010 wt % or less.

1 . An alloy comprising iron, nickel, and cobalt which are basic components of a Super Invar alloy, characterized in that an amount of a fraction which has not been carbidized in carbon contained in the alloy is 0.010 wt % or less. 
     
     
         2 . The alloy according to  claim 1 , characterized by further comprising carbide forming elements, wherein carbides formed from at least a part of the carbide forming elements and carbon are dispersed in a base phase. 
     
     
         3 . The alloy according to  claim 2 , characterized in that a total carbon content in the alloy is 0.010 wt % or more. 
     
     
         4 . The alloy according to  claim 3 , characterized in that the carbide forming elements are contained in a higher amount than the total carbon content in terms of atomic percent. 
     
     
         5 . The alloy according to  claim 2 , characterized in that a content of the carbide forming elements is 0.05 wt % or more and 0.50 wt % or less. 
     
     
         6 . The alloy according to  claim 2 , characterized in that an amount of carbide forming elements which have not been carbidized is 0.50 wt % or less. 
     
     
         7 . The alloy according to  claim 2 , characterized in that a compound phase of the nickel and the carbide forming elements is formed. 
     
     
         8 . The alloy according to  claim 2 , characterized in that the carbide forming elements are titanium or niobium. 
     
     
         9 . A lens holding member comprising the alloy according to  claim 1 . 
     
     
         10 . An optical apparatus comprising the lens holding member according to  claim 9 . 
     
     
         11 . A method for producing an alloy comprising iron, nickel, and cobalt which are basic components of a Super Invar alloy, characterized by comprising:
 adding carbide forming elements to the basic components and melt casting the resultant mixture;   hot forging at a predetermined temperature; and   precipitating carbides formed from carbons contained in the alloy and the carbide forming elements in a base phase by performing a first heat treatment at a first temperature which is lower than the predetermined temperature.   
     
     
         12 . The method for producing an alloy according to  claim 11 , characterized in that the first temperature is 825° C. or more and 950° C. or less. 
     
     
         13 . The method for producing an alloy according to  claim 11 , characterized in that a content of the added carbide forming elements is 0.05 wt % or more and 0.50 wt % or less. 
     
     
         14 . The method for producing an alloy according to  claim 11 , characterized by further comprising forming a compound phase of the nickel and the carbide forming elements by performing a second heat treatment at a second temperature which is lower than the first temperature. 
     
     
         15 . The method for producing an alloy according to  claim 11 , characterized by performing a third heat treatment at a third temperature which is lower than a Curie temperature of the alloy. 
     
     
         16 . The method for producing an alloy according to  claim 15 , characterized in that the third temperature is 80° C. or less.