阅读说明：本技术 金属粉末的颗粒的表面处理方法及由此获得的金属粉末颗粒 (Method for surface treatment of particles of metal powder and metal powder particles obtained thereby ) 是由 C·米科 J-L·贝津 于 2018-06-21 设计创作，主要内容包括：本发明涉及一种对金属粉末材料进行表面处理的方法,所述方法包括以下步骤：提供由多个待处理金属材料的颗粒形成的粉末,并通过将由例如电子回旋共振(ECR)型的单电荷或多电荷离子源产生的单电荷或多电荷离子束(14)引向所述颗粒的外表面对所述金属粉末进行离子注入过程,其中所述颗粒具有半径为R的总体球形。本发明还涉及由多个具有陶瓷外层(26)和金属核(24)的颗粒构成的粉末材料,所述颗粒具有半径为R的总体球形。(The invention relates to a method for surface treatment of a metal powder material, comprising the steps of: powder formed of a plurality of particles of a metallic material to be treated is provided and subjected to an ion implantation process by directing a single or multiple charged ion beam (14) generated by a single or multiple charged ion source, for example of the Electron Cyclotron Resonance (ECR) type, towards the outer surface of the particles, wherein the particles have a generally spherical shape with a radius R. The invention also relates to a powder material consisting of a plurality of particles having a ceramic outer layer (26) and a metal core (24), said particles having an overall spherical shape with a radius R.)

1. A method of surface-treating a metallic material in a powder state, the method comprising the steps of: obtaining a powder (30) formed of a plurality of particles of a metallic material to be treated, and subjecting the metallic powder particles (30) to an ion implantation process by directing a singly or multiply charged ion beam (14) generated by a singly or multiply charged ion source towards the outer surface of the particles, wherein the particles have a generally spherical shape with a radius R.

2. The method of claim 1, wherein the particles of the metal powder (30) are agitated throughout the ion implantation process.

3. The method according to any one of claims 1 or 2, characterized in that the grain size of the particles of the metal powder (30) used is such that substantially 50% of all the particles have a diameter in the range of 1 to 2 micrometers, wherein the diameter of the particles of the metal powder (30) does not exceed 50 micrometers.

4. The method according to any one of claims 1 to 3, wherein the metallic material is a noble metal selected from the group comprising gold and platinum.

5. A method according to any one of claims 1 to 3, characterized in that the metallic material is a non-noble metal selected from the group comprising magnesium, titanium and aluminium.

6. The method according to any one of claims 1 to 5, characterized in that the material to be ionized is selected from the group comprising carbon, nitrogen, oxygen and argon.

7. The method of claim 6, wherein the ion implantation process is of the ECR electron cyclotron resonance type.

8. The method of claim 7, wherein the singly or multiply charged ions are accelerated in a voltage range of 15,000 to 35,000 volts.

9. The method of claim 8, wherein the implanted ions have a dose of 1.10¹⁵To 1.10¹⁷Ion.cm^-2Within the range of (1).

10. The method according to any one of claims 8 or 9, wherein the ions penetrate to a depth corresponding to about 10% of the radius (R) of the particles forming the particles of metallic material powder.

11. Material in powder form, formed by a plurality of particles having a ceramic outer layer (26) and a metal core (24), wherein said particles have an overall spherical shape with a radius R, said ceramic outer layer (26) corresponding to a carbide or nitride of the metal of which the core (24) of said particles is made.

12. The material of claim 11, wherein about 50% of the particles have a diameter in the range of 1-2 microns, wherein the particles have a diameter of no more than 50 microns.

13. A material according to any one of claims 11 or 12, characterized in that the metallic material of which the particles of the metallic powder (30) are made is a noble metal selected from the group comprising gold and platinum.

14. A material according to any one of claims 11 or 12, characterized in that the metallic material of which the particles of the metallic powder (30) are made is a non-noble metal selected from the group comprising magnesium, titanium and aluminium.

15. A material according to any of claims 11 to 14, characterized in that the concentration of the ceramic material increases from the outer surface to about 5% of the length of the radius (R) of the particle and then decreases to about 10% of the length of the radius (R) of the particle, where it is substantially zero.

Disclosure of Invention

The object of the present invention is further to meet the above-mentioned need by proposing a method for the surface treatment of metallic materials which allows the production of objects with practically unlimited geometries, with improved and improved physical and chemical properties.

To this end, the invention relates to a method for the surface treatment of a metallic material, comprising the following steps: a powder formed of a plurality of particles of a metallic material is obtained, and a singly or multiply charged ion beam generated by a singly or multiply charged ion source is directed toward the surface of the particles, wherein the particles have an overall spherical shape.

According to a preferred embodiment of the invention:

-the single-or multi-charge ion source is of the ECR electron cyclotron resonance type;

-agitating the particles of the metal powder throughout the ion implantation process;

-the grain size of the particles of the metal powder used is such that substantially 50% of all of said particles have a diameter in the range of 1-2 microns, wherein the diameter of the particles of the metal powder used does not exceed 50 microns

-the metallic material is a noble metal selected from the group comprising gold and platinum;

-the metallic material is a non-noble metal selected from the group comprising magnesium, titanium and aluminium;

-the material to be ionized is selected from the group comprising carbon, nitrogen, oxygen and argon;

-singly or multiply charged ions are accelerated at a voltage of 15,000 to 35,000 volts;

the implanted ion dose is 1.10¹⁵To 1.10¹⁷Ion.cm^-2Within the range;

the maximum implantation depth of the ions is 150 to 200 nm.

The invention also relates to metal powder particles having a ceramic surface and a metal core, and more particularly having a surface corresponding to a carbide or nitride of the metal from which the metal powder particles are made.

As a result of these characteristics, the present invention provides a method for treating metallic materials in the powder state, in which the particles forming the powder retain their original metallic structure in depth, while from the surface up to a given depth, the singly or multiply charged ions that bombard the metallic powder particles fill defects in the crystal lattice of the metallic crystal structure and then combine with the atoms of the metallic material to form a ceramic, i.e. a material that is solid at ambient temperature, neither organic nor metallic.

It should be noted that after the ion implantation process, the metal powder particles are ready for powder metallurgy processes, such as injection molding, pressing or additive manufacturing, such as three-dimensional laser printing. Furthermore, the mechanical and physical properties of the metal powder particles, in particular the hardness, the corrosion resistance or the tribological properties, are improved as a result of the conversion of the surface of the metal powder particles into ceramics, in particular into carbides and/or nitrides of the metals constituting the particles. The improvement in mechanical and physical properties of the metal powder particles is retained when the metal powder is used to produce solid parts.

Preferably, the particles forming the metal powder are agitated throughout the ion implantation process so that they are exposed to the ions of the implantation beam in a uniform manner across their substantially spherical surface.

It should be noted that in the prior art, one method commonly used to obtain materials of the ceramic-metal type, called "cermets", consists in mixing metal and ceramic powders in as homogeneous a manner as possible, producing ceramic particles coated in a metal layer. However, this method presents the problem of how to precisely control the thickness of the metal layer and the quality of the interface between the metal layer and the ceramic core.