Method of manufacturing ni-based super heat resistant alloy extruded material, and ni-based super heat resistant alloy extruded material

Abstract

An Ni-based super heat resistant alloy extruded material manufacturing method includes: (1) obtaining an ingot by casting molten metal having a component composition of a precipitation-strengthened Ni-based super heat resistant alloy wherein the equilibrium precipitation amount of gamma prime at 700° C. is at least 40 mol % and using it as a billet, wherein the billet is heated to a hot working temperature that is at least 1030° C. and is less than the gamma prime solvus temperature of the alloy; and (2) inserting the billet that has been heated to the hot working temperature into a container, imparting a compressive force to the billet from one end side of the container, and extruding the billet at an extrusion rate of 10 to 300 mm/s from a hole in a die placed at the other end side of the container, to yield an Ni-based super heat resistant alloy extruded material.

1 . A method of manufacturing an extruded material of a precipitation strengthening type super heat resistant Ni-based alloy having such a composition that an amount of precipitated gamma prime in equilibrium at 700° C. is not less than 40 mol %, the method comprising:
 heating a billet made of the Ni-based alloy at a hot-working temperature; and 
 inserting the heated billet into a container, and applying a compressive force to the billet from one end of the container to extrude the billet through a hole of a dice at the other end of the container, thereby producing the extruded material of the Ni-based alloy, 
 wherein the billet is an ingot produced by casting a molten metal having the composition of the Ni-based alloy; and 
 wherein the hot-working temperature is not lower than 1030° C. but lower than a gamma prime solvus temperature of the billet of the Ni-based alloy, and the billet is extruded at an extruding speed of 10 to 300 mm/s. 
 
     
     
         2 . An extruded material of a super heat resistant Ni-based alloy, having a composition of a precipitation strengthening type super heat resistant Ni-based alloy wherein an amount of precipitated gamma prime in equilibrium at 700° C. is not less than 40 mol %, the material having an average grain size in a cross-sectional structure of not more than 20 μmin an equivalent circle diameter. 
     
     
         3 . The method according to  claim 1 , wherein the billet is a heat-treated ingot. 
     
     
         4 . The method according to  claim 3 , wherein a temperature of the heat treatment is 1170 to 1250° C. 
     
     
         5 . The method according to  claim 4 , wherein a time period of the heat treatment is 3 to 30 hours.