Device and method for producing metal powders
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 means of an active substance.
1 . A method for manufacturing powder from a first material and a second material, the manufacturing method comprising:
a step of melting the first and second materials, by an electric arc, to form first and second molten materials;
a step of spraying the first and second molten materials with a carrier gas so as to form droplets;
a step of cooling the droplets by the carrier gas and a cooling gas so as to form solid particles with a particle size distribution between 5 μm and 150 μm;
a step of enriching the droplets and/or the particles by an active substance, implemented during the cooling step, the enrichment step being preceded by a step of ionising the active substance; and
a step of separating the solid particles from the carrier gas and collecting the solid particles so as to form the powder,
wherein the carrier gas and the cooling gas present a volume flow ratio of 2 to 1.
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 cooling gas is injected at a temperature below 50° C.
5 . The manufacturing method according to claim 1 , wherein, in addition to the carrier gas, the cooling step is performed by a gas buffer.
6 . The manufacturing method according to claim 5 , wherein the temperature of the gas buffer is kept below 400° C.
7 . The manufacturing method according to claim 5 , wherein the gas buffer comprises a gas, the gas being argon.
8 . The manufacturing method according to claim 7 , wherein the speed of the gas within the gas buffer is less than 1 m/s.
9 . The manufacturing method according to claim 5 , wherein the manufacturing method is performed in sequences and wherein the sequences are spaced apart by times of cooling the gas buffer.
10 . 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.
11 . The manufacturing method according to claim 1 , wherein the collection step is followed by a step of passivating the particles.
12 . The manufacturing method according to claim 11 , wherein the passivation step is triggered when the maximum temperature of the powder is below a threshold temperature.
13 . The manufacturing method according to claim 11 , wherein the passivation step is triggered after a set waiting time.
14 . The manufacturing method according to claim 11 , wherein the duration of the passivation step is controlled as a function of the temperature of the powder.
15 . The manufacturing method according to claim 11 , wherein the duration of the passivation step is set.
16 . The manufacturing method according to claim 1 , wherein the particle size distribution of the solid particles is between 10 μm and 63 μm.