Method for producing platinum group metal or platinum group-based alloy

Abstract

A method for producing a platinum group metal or a platinum group-based alloy according to the present invention includes a preparing step of weighing a raw material that is partially or entirely of powder, a molding step of molding and solidifying the prepared raw material to obtain molded bodies, a sintering step of sintering the molded bodies to obtain a sintered body, a melting step of melting the sintered body to produce a molten ingot, and a deformation processing step of processing the molten ingot. In the sintering step, the molded bodies are sintered in a stacked state to produce a sintered body as a joined body.

1 . A method for producing a platinum group metal or a platinum group-based alloy, comprising:
 a preparing step of weighing a raw material that is partially or entirely of powder and, when the alloy is to be produced, mixing the weighed raw material to obtain a powder mixture;   a molding step of molding and solidifying the prepared raw material to obtain molded bodies;   a sintering step of sintering the molded bodies in a furnace to obtain a sintered body as a joined body;   a melting step of melting the sintered body to produce a molten ingot; and   a deformation processing step of processing the molten ingot,   wherein, in the sintering step, the molded bodies are sintered in the furnace in a stacked state to produce the sintered body having a relative density of 70% or more.   
     
     
         2 . A method for producing a platinum group metal or a platinum group-based alloy according to  claim 1 , wherein, in the molding step, the molded bodies are substantially in the shape of a rectangular parallelepiped. 
     
     
         3 . A method for producing a platinum group metal or a platinum group-based alloy according to  claim 1 , wherein, in the melting step, a pressure during the melting is 1 Pa or higher. 
     
     
         4 . A method for producing a platinum group metal or a platinum group-based alloy according to  claim 3 , wherein, in the melting step,
 a plasma arc melting furnace with a water-cooled copper crucible having a through cavity is used,   a molten pool of a molten metal of the sintered body is formed in the cavity, and   a bottom portion of the molten pool in the cavity is pulled down to obtain the molten ingot.   
     
     
         5 . A method for producing a platinum group metal or a platinum group-based alloy according to  claim 2 , wherein, in the melting step, a pressure during the melting is 1 Pa or higher.