Device and method for producing metal powders

Abstract

A method of manufacturing powder from a first and a second materials for use in additive manufacturing, the manufacturing process including melting the first and second materials by an electric arc; spraying the melted materials so as to form droplets; cooling the droplets by a carrier gas so as to form solid particles; separating the solid particles from the carrier gas and collecting the solid particles so as to form the powder; and enriching the droplets and/or the particles by an active substance.

1 . A method for manufacturing powder from a first material and a second material ( 1   b ), the manufacturing method comprising:
 a step of melting the first and second materials, by an electric arc;   a step of spraying the first and second materials molten so as to form droplets;   a step of cooling the droplets by a carrier gas so as to form solid particles;   a step of enriching the droplets and/or the particles by an active substance, implemented during the cooling step; and   a step of separating the solid particles from the carrier gas and collecting the solid particles so as to form the powder,   
       in addition to the carrier gas, the cooling step is performed in an atomisation chamber by a gas buffer, an exhaust means being connected to the atomisation chamber so as to create said gas buffer. 
     
     
         2 . The manufacturing method according to  claim 1 , wherein the active substance comprises:
 at least one neutral 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 gas, liquid or solid phase, the content of each active compound being between 5 ppm and 20,000 ppm. 
     
     
         3 . The manufacturing method according to  claim 1 , wherein the enrichment step is implemented during the spraying and cooling steps. 
     
     
         4 . The manufacturing method according to  claim 1 , wherein the enrichment step is preceded by a step of ionising the active substance. 
     
     
         5 . The manufacturing method according to  claim 1 , wherein, in addition to the carrier gas, the cooling step is performed by means of a cooling gas. 
     
     
         6 . The manufacturing method according to  claim 5 , wherein the cooling gas is injected at a temperature below 50° C. 
     
     
         7 . The manufacturing method according to  claim 1 , wherein the temperature of the gas buffer is kept below 400° C. 
     
     
         8 . The manufacturing method according to  claim 1 , wherein the gas buffer comprises a gas, the gas being argon. 
     
     
         9 . The manufacturing method according to  claim 8 , wherein a speed of the gas within the gas buffer is less than 1 m/s. 
     
     
         10 . The manufacturing method according to  claim 1 , wherein the manufacturing method is performed in sequences. 
     
     
         11 . The manufacturing method according to  claim 1 , wherein the steps of the method are implemented by a manufacturing device, said method comprising a step of inerting the manufacturing device by a neutral gas, for purging the manufacturing device, the melting step being triggered subsequently to the inerting step. 
     
     
         12 . The manufacturing method according to  claim 1 , wherein the collection step is followed by a step of passivating the particles. 
     
     
         13 . The manufacturing method according to  claim 12 , wherein the passivation step is triggered when a maximum temperature of the powder is below a threshold temperature. 
     
     
         14 . The manufacturing method according to  claim 12 , wherein the passivation step is triggered after a set waiting time. 
     
     
         15 . The manufacturing method according to  claim 12 , wherein a duration of the passivation step is controlled as a function of the temperature of the powder. 
     
     
         16 . The manufacturing method according to  claim 12 , wherein the duration of the passivation step is set. 
     
     
         17 . A device for manufacturing powder from a first material and a second material, configured to perform the manufacturing method according to  claim 1 , the manufacturing device including:
 a spraying means;   an atomisation chamber;   a first collection means; and   an exhaust means, connected to the atomisation chamber so as to create a gas buffer.   
     
     
         18 . The manufacturing device according to  claim 17 , wherein the exhaust means is connected to the atomisation chamber at a height from the lowest point of the atomisation chamber greater than 500 mm. 
     
     
         19 . The manufacturing device according to  claim 17 , wherein a heat regulation system is installed on walls of the atomisation chamber. 
     
     
         20 . The manufacturing device according to  claim 17 , wherein the spraying means comprises a wire arc torch configured to generate an electric arc between the first material and the second material. 
     
     
         21 . The manufacturing device according to  claim 17 , including a gas/particle separation system connected to the exhaust means, the gas/particle separation system including an outlet connected to a second collection means.