Steel powder mixture for additive manufacturing of parts, preferably for manufacturing parts for machine construction and automotive manufacturing
A low-alloy steel powder mixture with tailored composition and size distribution addresses the strength and weldability issues of existing powders, enabling efficient additive manufacturing of machinery and vehicle parts without post-treatment, reducing scrap and storage costs.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-02-02
- Publication Date
- 2026-03-10
AI Technical Summary
Existing steel powders for additive manufacturing, particularly in selective laser melting, are not optimized for machine and vehicle construction, lacking the necessary strength and weldability required for machinery and vehicle parts, and often necessitate costly post-treatment processes.
A low-alloy steel powder mixture with specific composition and particle size distribution, providing high strength, weldability, and machinability, eliminating the need for subsequent heat treatment, suitable for additive manufacturing of machinery, vehicle, and steel structures.
The steel powder mixture achieves high yield strength, tensile strength, and excellent weldability, enabling rapid production of complex parts with minimal scrap and storage costs, suitable for machine and vehicle construction without requiring post-treatment.
Smart Images
Figure 2026508260000001 
Figure 2026508260000002 
Figure 2026508260000003
Abstract
Description
[Technical Field]
[0001] The present invention relates to a steel powder mixture for the additive manufacturing of parts, preferably for producing parts for, for example, machine and vehicle construction, agricultural and forestry machinery, and steel construction. [Background technology]
[0002] It is known that selective laser melting (SLM) is used in the powder bed method to manufacture parts in an additive manufacturing process also known as 3D printing, in which the part structure is produced by layer-by-layer melting and hardening of the steel powder mixture used.
[0003] EP 3591078 discloses the use of steel powder for additive manufacturing processes, the steel having an average particle size of 5-150 μm, the steel containing (units: weight-%) 0.008-0.35% C, max 0.80% Si, 0.20-2.00% Mn, max 4.00% Cr, 0.3-3.0% Mo, 0.004-0.020% N, max 0.40% S, 0.004-0.050% Al, max 0. It consists of 0.025% B, max 0.20% Nb, max 0.02% Ti, max 0.40% V, max 1.5% Ni, max 0.3% Cu, max 2.0% Co, and the remainder iron and unavoidable impurities, and the Al content (%Al), Nb content (%Nb), Ti content (%Ti), V content (%V) and N content (%N) of the steel satisfy the following conditions: %Al / 27+%Nb / 45+%Ti / 48+%V / 25>%N / 3.5.
[0004] From WO 2020221812 a steel material in powder form is known which is used for printing in additive manufacturing methods such as selective laser melting, this material having the following composition: 0.17-0.23 C; 0.10-0.80 Si; 0.15-0.45 Mn, P≦0.03; S≦0.015; 0.8-2.0 Cr; 0.15-0.8 Mo; 0.1-2.0 Ni; 0.1-2.0 V, the remainder being iron.
[0005] These known steels are primarily stainless steels or tool steels used in tool construction. Summary of the Invention
[0006] The object of the present invention is to indicate a steel powder mix for additive manufacturing of parts, which powder mix meets the requirements in particular of machine and vehicle construction.
[0007] The invention results from the features of the independent claims. Advantageous further developments and configurations are the object of the dependent claims. Further features, possible applications and advantages of the invention can be gleaned from the following description and from the description of exemplary embodiments of the invention.
[0008] The object is achieved by the subject matter of patent claim 1.
[0009] The steel powder mixture detailed above has a strength of at least 800 N / mm 2 High yield strength and yield point, up to 18% breaking strength, up to 900N / mm 2 It consists of a low-alloy steel with a tensile strength of 1000 MPa and a hardness of approximately 30 HRC. These properties make the powder particularly suitable for the manufacture of machinery and vehicle parts, agricultural and forestry parts, and steel structures, as it does not require subsequent heat treatment. Machinery and vehicle parts, agricultural and forestry parts, and steel structures can be manufactured in any quantity, which means that expensive warehouse storage is no longer an issue. A reduction in scrap material costs is also achieved (resource conservation).
[0010] Advantageously, the low alloy steel consists of (in weight-%) 0.05% C, 0.5% Si, 1.1% Mn, 0.01% P, 0.002% S, 0.01% Al, 0.002% Ti, 0.01% V, 0.06% Nb, 0.04% N and 0.04% O, balance Fe.
[0011] In one configuration, the powder has particles with a particle size of 23 μm to 50 μm, with particle size distributions of D10 to 23 μm, D50 to 34.0 μm, and D90 to 50 μm.
[0012] Components manufactured by additive manufacturing processes from the described steel powder mixtures are highly machinable, deformable and feature very good weldability, making them particularly suitable for hybrid manufacturing processes.
[0013] A further aspect of the present invention relates to a method for generative manufacturing of parts, in which a selective laser melting process is used as a 3D printing process in a powder bed process, where the part structure produced in the laser melting process is due to layer-by-layer melting and hardening of a steel powder mixture, where the steel powder mixture has at least one of the features described in this patent application. Such a method facilitates short manufacturing times, whereby products manufactured using this method are ready for further use within a very short time without the need for complex tooling design. Advantageously, parts can be manufactured to customer specifications. It also bridges downtime caused by supply gaps, as occurs in traditional manufacturing.
[0014] Biocompatible products can be created according to individual requirements. Additively manufactured lattice structures reduce the weight of the part. Because the structures are highly complex, selective laser melting is particularly well suited to the production of additively manufactured lattice structures due to its targeted geometric effects. The layer-by-layer construction allows the manufactured part to take on any shape. The method-dependent shaping freedom makes it possible to produce parts that cannot be produced using conventional methods. Furthermore, it is possible to design new products with performance characteristics that could not be achieved using conventional manufacturing methods.
[0015] Further advantages, features and details can be gleaned from the following description in which at least one exemplary embodiment is described in detail. The features described and / or represented diagrammatically may constitute an object of the invention on their own or in any reasonable combination and may optionally be independent of the claims and may further in particular be the object of one or more separate applications. DETAILED DESCRIPTION OF THE INVENTION
[0016] Below, an exemplary embodiment of the steel powder mixture according to the invention is described in Table 1, which is used for additive manufacturing of parts in 3D printing methods, for machine and vehicle structures as well as agricultural and forestry vehicles, steel structures, etc. Manufacturing is carried out in the powder bed method, in which the steel powder mixture is melted and then hardened layer by layer by a laser beam. [Table 1] Table 1
[0017] In this process, the particle size distribution is such that 10% of the particles (D10) are smaller than 23 μm, 50% of the particles (D50) are smaller than 34 μm, and 90% of the particles (D90) are smaller than 50 μm.
[0018] Metal parts manufactured using this steel powder mixture have excellent yield strength and yield point for the manufacture of machine and vehicle parts. In addition, they have an elongation at break of up to 18% and a maximum of 900 N / mm 2 The alloy achieves a tensile strength of approximately 30. No subsequent heat treatment is required. The metal alloy has a hardness (HRC) of approximately 30.
Claims
1. At least 800 N / mm ２ High yield strength and yield point, breaking strength up to 18%, up to 900 N / mm ２ and a hardness of about 30 HRC.
2. The low alloy steel is composed of (unit: weight-%) 0.05% C, 0.5% Si, 1.1% Mn, 0.01% P, 0.002% S, 0.01% Al, 0.002% Ti, 0.01% V, 0.06% Nb, 0.04% N and 0.04% O, the balance being Fe. characterized in that 2. The steel powder mixture of claim 1.
3. Particles with a particle size of 23 μm to 50 μm characterized by:
3. A steel powder mixture according to claim 1 or 2.
4. The particle size distribution of the powder is D10 about 23 μm, D50 about 34.0 μm, and D90 about 50 μm. characterized in that 4. A steel powder mixture according to claim 1, 2 or 3.
5. A method for generative manufacturing of parts in which a selective laser melting process is used as a 3D printing process in a powder bed process, wherein the part structure produced in said laser melting process is due to layer-by-layer melting and hardening of a steel powder mixture; 5. A method, characterized in that a steel powder mixture according to any one of claims 1 to 4 is used.