Method for the surface treatment of particles of a metal powder and metal powder particles obtained thereby

A method for surface treatment of a metal material in a powder state, the method comprising:

• obtaining a powder formed from a plurality of particles of the metal material to be treated;
• and
• subjecting the powder formed from the plurality of particles of the metal material to an ion implantation process by directing a beam of singly-charged or multi-charged ions towards an outer surface of the particles,
• wherein the beam is produced by a source of singly-charged or multi-charged ions,
• wherein the particles have an overall spherical shape with a radius (R),
• wherein the singly-charged or multi-charged ions penetrate the particles to form a carbide layer up to a depth corresponding to about 10% of the radius (R) of the particles,
• wherein a concentration of material of the carbide layer increases from an outer surface of the particle of the metal material to 5% of the radius (R), then decreases to 10% of the radius (R) where it is zero,
• wherein the metal material is gold or platinum, and
• wherein the ions are chosen from carbon ions and nitrogen ions.