Noble-metal powder and the use thereof for producing components

• US 10,744,590 B2
• Filed: 03/03/2017
• Issued: 08/18/2020
• Est. Priority Date: 03/07/2016
• Status: Active Grant

• Current Assignee: Haraeus Deutschland GmbH & Co. KG
• Original Assignee: Haraeus Deutschland GmbH & Co. KG
• Inventors: Maier, Dirk, Humm, Stephan
• Primary Examiner(s): Abraham, Ibrahime A
• Assistant Examiner(s): Norton, John J
• Application Number:
  US15/449,081
• Publication Number:
  US 20170252854A1
• Time in Patent Office: 1,264 Days
• CPC Class Codes: B22F 1/052 characterised by a mixture of particles of different sizes or by the particle size distribution
• CPC Class Codes: B22F 1/065 Spherical particles
• CPC Class Codes: B22F 10/28 Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
• CPC Class Codes: B22F 10/34 of powder characteristics, e.g. density, oxidation or flowability
• CPC Class Codes: B22F 10/64 by thermal means control of energy beam parameters for post heating B22F10/364
• CPC Class Codes: B23K 15/0086 welding for purposes other than joining, e.g. built-up welding
• CPC Class Codes: B23K 26/342 Build-up welding
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: C22C 1/0466 Alloys based on noble metals
• CPC Class Codes: Y02P 10/25 Process efficiency

Abstract

The present invention relates to a powder composed of spherical noble-metal particles having a particle size distribution with a d₁₀ value of ≥10.0 μm and a d₉₀ value of ≤80.0 μm.

Claims

1. A powder composed of spherical noble-metal particles having a particle size distribution with a d₁₀ value of ≥

10.0 μ

m and a d₉₀ value of ≤

80.0 μ

m, and wherein the noble-metal particles have a mean crystallite size ≥

200 nm.

2. The powder according to claim 1, wherein the noble metal is a platinum-group metal, gold or silver or an alloy composed of at least two of the aforementioned noble metals.

3. The powder according to claim 2, wherein the platinum-group metal is platinum, iridium, palladium, ruthenium, rhodium or osmium or an alloy composed of at least two of the aforementioned platinum-group metals.

4. The powder according to claim 1, wherein the noble-metal particles contain elements which are not noble metals in a proportion of not more than 0.1% by weight.

5. The powder according to claim 1, wherein the d₉₀ value and the d₁₀ value differ by at least 15 μ

m.

6. The powder according to-claim 1, wherein the d₁₀ value is within the range from 10.0 to 35.0 μ

m, and/or the d₉₀ value is within the range from 40.0 to 80.0 μ

m.

7. The powder according to-claim 1, wherein the noble metal is iridium, the d₁₀ value is within the range from 20.0 to 30.0 μ

m, the d₉₀ value is within the range from 40.0 to 80.0 μ

m, and the difference between the d₉₀ value and the d₁₀ value is at least 20 μ

m.

8. The powder according to-claim 1, wherein the powder satisfies the following condition:

F/ρ

_TH≤

0.30 s/(50 cm³)

where F is the flowability of the powder in s/(50 g), determined in accordance with DIN EN ISO 4490;

2014-11, and

Σ

_TH is the theoretical density in g/cm³ of the noble metal forming the noble-metal particles.

9. The powder according to claim 1, wherein, based on the number of noble-metal particles, at least 80% of the noble-metal particles satisfy the following condition:

0.8≤

d_min/d_max≤

1.0;

where d_min and d_max are the minimum diameter and the maximum diameter, respectively, of the noble-metal particle.

10. The powder according to claim 1, wherein the powder is obtained via an atomization of liquid noble metal, and optionally a classification carried out after the atomization.

11. A component comprising the powder according to claim 1, wherein the component is obtained via an additive manufacturing process and has a porosity of less than 10%.

12. An additive manufacturing process for producing a component, comprising the following steps:

(a) applying the powder according to claim 1, in the form of a first layer to a substrate in a construction space,

(b) at least partially melting the powder of the first layer using radiation and allowing solidification of the melted powder,

(c) applying a further layer of the powder to the first layer,

(d) at least partially melting the powder of the further layer using radiation and allowing solidification of the melted powder, and

(e) repeating steps (c) and (d).