Process for preparing powder

Abstract

A preparation process for preparing powder from a first material and a second material, having: a step of dispensing wires made of the materials by means of a feeder and an additional feeder, a melting step of melting the wires, a spraying step of spraying in such a way as to form droplets, a cooling step of cooling the droplets in such a way as to form solid particles, a separation and collection step of separating the solid particles from the carrier gas and collecting the solid particles so as to form the powder, and, during the dispensing step, the wires are firstly pushed by the feeder, then pulled by the additional feeder, and then pushed by the additional feeder towards said electric arc.

1 . A process for preparing powder from a first material and a second material, comprising:
 dispensing a first wire and a second wire made of the first material and the second material, respectively, said dispensing step being carried out for each wire by at least a feeder and an additional feeder;   melting the first and second materials, with an electric arc formed by the application of an electric current between said first and second materials;   spraying the first and second molten materials thereby forming droplets;   cooling the droplets with a carrier gas thereby forming solid particles;   separating the solid particles from the carrier gas and collecting the solid particles thereby forming the powder,   wherein, during said dispensing step, said first wire and said second wire are pushed by said feeder towards said electric arc, then said first wire and said second wire are pulled towards said electric arc by said additional feeder, and then said first wire and said second wire are pushed by said additional feeder towards said electric arc.   
     
     
         2 . The process according  claim 1 , wherein said first wire and said second wire each have an end which is melted during said melting step, said first wire and said second wire are each pushed by said additional feeder over a distance (L), each distance (L) being equal to the length measured between said additional feeder and said respective end of the wires. 
     
     
         3 . The process according to  claim 1 , wherein said first and second wires are dispensed at a rate of between 5 and 10 m/min. 
     
     
         4 . The process according to  claim 1 , further comprising an additional step of analyzing the powder to determine the density of said powder and/or the oxygen content of said powder and/or the particle size of said powder. 
     
     
         5 . The n process according to  claim 1 , further comprising an enriching step of enriching the droplets and/or the particles with an active substance which is carried out during the cooling step, the enriching step being preceded by a step of ionizing the active substance. 
     
     
         6 . The process according to  claim 1 , wherein the enriching step is carried out during the spraying and cooling steps. 
     
     
         7 . The process according to  claim 1 , wherein the cooling step is carried out using a cooling gas in addition to the carrier gas. 
     
     
         8 . The preparation process according  claim 5 , wherein the active substance comprises:
 at least one inert gas; and   at least one active compound comprising at least one of the following atoms: oxygen, nitrogen, carbon or hydrogen; each active compound being in the gaseous, liquid or solid phase, the content of each active compound being between 5 ppm and 20000 ppm.