Additively manufactured printable hard ferrous metal alloys via direct energy deposition

Abstract

The present invention provides a printed metal part. The alloy has the following composition: 69.2 to 89.1 wt.% Fe; 7.25 to 16.0 wt.% Cr; 0.01 to 10.0 wt.% Nb; 0.5 to 4.0 wt.% Mo; 0.03 to 0.4 wt.% C; and optionally one or more of Ni, Cu, Si, W, Mn, N, and B. The printed metal part has a tensile strength of at least 1300 MPa, a yield strength of at least 700 MPa, an elongation of at least 4.0%, and a hardness of at least 45 HRC.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 009,818, filed April 14, 2020, which is incorporated herein by reference in its entirety. Technical Field

[0003] The present application relates to ferrous alloy compositions for producing metal parts using direct energy deposition additive manufacturing or 3D printing methods. Background Art

[0004] Additive manufacturing, also known as 3D printing, typically involves the layer-by-layer deposition of material to "build" or "print" three-dimensional parts. Manufacturing with this method offers many advantages over traditional subtractive manufacturing methods, including the ability to produce complex geometries that would otherwise be impossible to manufacture, faster part production times, and material cost savings.

[0005] There are several processes used for metal 3D printing. In one subset, a metal precursor, either in wire or powder form, is melted using a focused energy source (such as a laser or electron beam) and then "directed" to a specific location on the part being built, where it solidifies in a "deposition" manner. This process is generally called directed energy deposition (DED), and its common variants are called direct laser deposition (DLD), laser engineered net shaping (LENS), direct metal deposition (DMD), shaped metal deposition (SMD), and laser metal deposition (LMD). For the purposes of this disclosure, these processes are generally referred to as DED to be independent of the power source. Summary of the Invention

[0006] In at least one embodiment, ferrous alloy compositions are provided that, when manufactured using direct energy deposition additive manufacturing or 3D printing methods, can produce metal parts with relatively high hardness, strength, and / or ductility. These properties are achieved by formulating the chemical composition of these alloys to form phases and microstructures under the processing conditions (i.e., time and temperature) experienced during direct energy deposition.

[0007] In at least one embodiment, a method for building a component layer by layer by direct energy deposition is provided. The alloy is provided in powder or granular form and has a composition of 69.2 wt.% to 89.1 wt.% Fe; 7.25 wt.% to 16.0 wt.% Cr; 0.01 wt.% to 10.0 wt.% Nb; 0.5 wt.% to 4.0 wt.% Mo; 0.03 wt.% to 0.4 wt.% C, and optionally one or more of Ni, Cu, Si, W, Mn, N, and B. One or more layers of the alloy are applied to a substrate by melting the alloy to a molten state and cooling and solidifying. The metal component has a tensile strength of at least 1300 MPa, a yield strength of at least 700 MPa, an elongation of at least 4.0%, and a hardness of at least 45 HRC.

[0008] According to another embodiment, one or more of Ni, Cu, Si, W, Mn, N and B is optional, and if present, falls within the following ranges: Ni (1.5 wt.% to 4.0 wt.%), Cu (0.1 wt.% to 3.0 wt.%), Si (0.1 wt.% to 1.0 wt.%), W (0.1 wt.% to 6.0 wt.%), Mn (0.4 wt.% to 1.9 wt.%), N (0.03 wt.% to 1.0 wt.%) and B (0.01 wt.% to 0.05 wt.%).

[0009] According to another embodiment, the layer has a thickness of 20 μm to 1000 μm thick.

[0010] According to another embodiment, the metal deposition rate is generally about 0.5 kg / hr to 10 kg / hr.

[0011] In at least one embodiment, a printed metal part is provided. The alloy has the following composition: 69.2 wt.% to 89.1 wt.% Fe; 7.25 wt.% to 16.0 wt.% Cr; 0.01 wt.% to 10.0 wt.% Nb; 0.5 wt.% to 4.0 wt.% Mo; 0.03 wt.% to 0.4 wt.% C, and optionally one or more of Ni, Cu, Si, W, Mn, N, and B. The printed metal part has a tensile strength of at least 1300 MPa, a yield strength of at least 700 MPa, an elongation of at least 4.0%, and a hardness of at least 45 HRC.

[0012] According to another embodiment, the printed metal part has a tensile strength of at least 1300 MPa and up to 2200 MPa, a yield strength of at least 700 MPa and up to 1500 MPa, an elongation of at least 4% and up to 20%, and a hardness of at least 45 HRC and up to 58 HRC.

[0013] According to another embodiment, the alloy includes 82.0 wt.% to 87.0 wt.% Fe; 10.5 wt.% to 12.0 wt.% Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.02 wt.% to 0.05 wt.% Nb; 0.1 wt.% to 0.6 wt.% Cu; 1.2 wt.% to 1.8 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.15 wt.% to 0.22 wt.% C; and 0.03 wt.% to 0.08 wt.% N.

[0014] According to another embodiment, the alloy includes 82.0 wt.% to 87.0 wt.% Fe; 11.0 wt.% to 13.5 wt.% Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.02 wt.% to 0.05 wt.% Nb; 0.1 wt.% to 0.4 wt.% Cu; 1.5 wt.% to 2.1 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.17 wt.% to 0.25 wt.% C; and 0.02 wt.% to 0.06 wt.% N.

[0015] According to another embodiment, the alloy includes 79.0 wt.% to 83.0 wt.% Fe; 10.5 wt.% to 12.0 wt.% Cr; 2.8 wt.% to 3.8 wt.% Ni; 0.04 wt.% to 0.08 wt.% Nb; 0.1 wt.% to 0.6 wt.% Cu; 2.5 wt.% to 3.5 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.1 wt.% to 1.0 wt.% W; 0.20 wt.% to 0.25 wt.% C; and 0.05 wt.% to 0.13 wt.% N.

[0016] According to another embodiment, the alloy includes 79.0 wt.% to 83.0 wt.% Fe; 7.7 wt.% to 9.0 wt.% Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.04 wt.% to 0.08 wt.% Nb; 1.2 wt.% to 1.8 wt.% Mo; 4.1 wt.% to 5.5 wt.% W; 0.4 wt.% to 1.1 wt.% Mn; 0.15 wt.% to 0.22 wt.% C; 0.05 wt.% to 0.13 wt.% N; and 0.01 wt.% to 0.05 wt.% B.

[0017] BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is LENSTM Optical microscope micrograph of the as-built Alloy A1 of 850-R build.

[0019] Figure 2 After etching, LENS TM Optical microscope micrograph of the as-built Alloy A1 of the 850-R build to show the microstructure.

[0020] Figure 3 After etching, LENS TM Scanning electron microscope (SEM) micrograph of the as-built Alloy A1 of the 850-R build to show the microstructure.

[0021] Figure 4 is LENS TM X-ray diffraction spectrum of the as-built alloy A1 from 850-R.

[0022] Figure 5 This is the equilibrium phase diagram of Alloy A1 calculated using Thermo Calc software.

[0023] Figure 6 This is the equilibrium phase diagram of alloy A2 calculated using Thermo Calc software.

[0024] Figure 7 This is the equilibrium phase diagram of alloy A3 calculated using Thermo Calc software.

[0025] Figure 8 This is the equilibrium phase diagram of alloy A4 calculated using Thermo Calc software. DETAILED DESCRIPTION

[0026] As required, detailed embodiments of the present invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely exemplary embodiments of the invention, which may be embodied in various and alternative forms. The drawings are not necessarily drawn to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, the specific structural and functional details disclosed herein should not be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to employ the present invention in various ways.

[0027] The Directed Energy Deposition (DED) process for metal 3D printing uses a feed nozzle to propel powder toward an energy source. This enables DED to manufacture relatively large products and achieve faster printing speeds than additive manufacturing processes using a powder bed. In addition to high productivity, DED's advantages include the ability to clad or repair previously produced parts, as well as create multi-material components.

[0028] The DED process can also take advantage of certain conditions during processing, such as sustained baseline high temperatures, periodic thermal excursions, and rapid cooling rates, which can be used to form and develop ideal phases and microstructures that produce unique properties. While historically wrought or cast steel alloys have been used in DED systems, including 316L, 17-4PH, H13, and M300, they were not developed with the DED process in mind. Therefore, there is an opportunity to develop new steel alloy compositions specifically for DED that can achieve similar or better mechanical properties than current wrought or cast alloys.

[0029] The present application discloses metal alloy compositions that exhibit a combination of printability and mechanical properties via direct energy deposition (DED) methods. Specifically, the metal alloy compositions can have a relatively high hardness (45HRC to 58HRC), a relatively high strength (yield strength of 700MPa to 1500MPa, a tensile strength of 1300MPa to 2200MPa), and / or a relatively high ductility (elongation of 4% to 20%) in an "as-built" state.

[0030] In the context of DED-based additive manufacturing, printability refers to the ability of a metal alloy to be printed on a DED machine. Prints should be free of defects that would affect the use of the printed part in a specific application, such as cracks and pores, without applying conditions that would hinder the process, such as elevated process temperatures or times. The "as-built" condition is defined as the condition produced by the DED machine, which may not include any post-printing treatments to control the microstructure, such as heat treatment. The "heat-treated" state refers to the state of the printed metal after exposure to a thermal process designed to alter the microstructure to achieve specific properties.

[0031] The present invention relates to an alloy containing the following elements in concentrations: 69.2 wt.% to 89.1 wt.% Fe, 7.2 wt.% to 16.0 wt.% Cr, up to 4.0 wt.% Ni, 0.01 wt.% to 10.0 wt.% Nb, up to 3.0 wt.% Cu, 0.5 wt.% to 4.0 wt.% Mo, up to 1.0 wt.% Si, up to 6.0 wt.% W, up to 1.9 wt.% Mn, 0.03 wt.% to 0.4 wt.% C, up to 1.0 wt.% N and up to 0.25 wt.% B. Therefore, Ni, Cu, Si, W, Mn, N and B are optional and, if present, may be in the following ranges: Ni (1.5 wt.% to 4.0 wt.%), Cu (0.1 wt.% to 3.0 wt.%), Si (0.1 wt.% to 1.0 wt.%), W (0.1 wt.% to 6.0 wt.%), Mn (0.4 wt.% to 1.9 wt.%), N (0.03 wt.% to 1.0 wt.%) and B (0.01 wt.% to 0.05 wt.%).

[0032] In at least one embodiment, for low environmental, health, and safety (EH&S) risk, the alloy is Co-free. That is, the Co content may be less than 0.1 wt.%. In another embodiment, the content is less than 0.05 wt.%. Some embodiments may be free of tungsten (W), manganese (Mn), or boron (B). Some embodiments contain W; some embodiments contain Mn; some embodiments contain both W and Mn; and some embodiments contain B.

[0033] Table 1 lists examples of embodiments of alloys according to the present invention.

[0034] Table 1

[0035]

[0036] The alloy can be provided for the DED process in the form of particles produced by conventional methods. The particles can be produced using either gas or water atomization processes, the former using nitrogen or argon. The particles can have a diameter of 1 μm to 500 μm. In another embodiment, the particles can have a diameter of 10 μm to 300 μm. In another embodiment, the particles can have a diameter of 45 μm to 250 μm.

[0037] DED parts can be made using commercial DED machines such as LENS TM850-R, constructed from a metal alloy. The part can be constructed in an inert atmosphere, such as argon. The part can be constructed on a substrate preheated to up to 800°C. In another embodiment, the substrate can be preheated at 50°C to 200°C. In another embodiment, the substrate can be preheated at 50°C to 100°C. In addition, the substrate cannot be preheated. The metal substrate can be constructed from 1018 steel. However, it is contemplated that other steels and non-ferrous alloys can be used as the substrate.

[0038] The DED process herein contemplates the accumulation of alloy layers, each layer having a thickness of 20 μm and greater. In one embodiment, the thickness of the alloy layers is 20 to 2000 μm. In another embodiment, the thickness of the alloy layers is 40 to 1000 μm. In another embodiment, the thickness of the alloy layers is 100 to 800 μm.

[0039] The beam diameter may be between 0.1 mm and 50 mm. In another embodiment, the beam diameter may be between 0.4 mm and 10 mm. In another embodiment, the beam diameter may be between 0.6 mm and 4 mm.

[0040] The writing speed of the print nozzle can be between 2.5 and 250 cm / min. In another embodiment, the writing speed of the print nozzle is between 50 and 150 cm / min. In another embodiment, the writing speed of the print nozzle is between 75 and 105 cm / min.

[0041] The construction method includes depositing the metal powder by melting it in an atmosphere having an oxygen content of less than or equal to 50 ppm. In another embodiment, the atmosphere may have an oxygen content of less than or equal to 40 ppm, or ≤30 ppm oxygen, or ≤20 ppm oxygen, or ≤10 ppm oxygen, or ≤5 ppm oxygen, or ≤1.0 ppm oxygen, and is directed to a designated location on the substrate at room temperature, or preheated at 50°C to 800°C while it solidifies. It is expected that in one embodiment, the oxygen level may be between 0.1 ppm and 50 ppm. In another embodiment, the oxygen level may be between 0.1 ppm and 10 ppm. In another embodiment, the oxygen level may be between 0.1 ppm and 5.0 ppm. In another embodiment, the oxygen level may be between 0.1 ppm and 2.5 ppm.

[0042] Because defects such as pores and cracks can negatively impact part performance, it is preferred that defects in finished parts made from these alloys be minimized using the DED process. Specifically, the average porosity in the part can be less than 1.0%. In another embodiment, the average porosity in the part can be less than 0.5%. In another embodiment, the average porosity in the part can be less than 0.3%. The finished parts of the metal alloys described herein have low porosity and are crack-free. Pass Error! No cross-sectional optical microscopy images shown in the referenced source were found to confirm that the part was passed LENS TM The 850-R component is made from Alloy A1. The component was fabricated on a 1018 steel substrate using layers 0.5mm to 1mm thick, without preheating, and at a height of 25mm. The average porosity was 0.22%, as measured according to ASTM E1245-03 (2016), which involves optical image analysis of micrographs taken at 50x magnification of a metallographic cross-section of the component.

[0043] Table 2 shows the mechanical properties of finished components produced using conventional commercial steel alloys using DED compared to the A1, A2, A3 and A4 alloys described in this paper in Table 1. LENS TM The properties of the A1, A2, A3, and A4 alloys were measured on 850-R parts built on a 1018 substrate with a height of 25 mm without preheating. Notably, the yield strength and tensile strength of the alloy A1 described herein exceed those of currently available steels also produced using DED, including 316L, M300, 17-4PH, and H13. Furthermore, the alloy A1 exhibits a combination of high strength and elongation (i.e., ductility) not found in currently available steels.

[0044] Table 2

[0045]

[0046] As shown in Table 2, the alloys described herein have a high tensile strength of at least 1300 MPa in the as-built condition. In another embodiment, the alloy in the as-built condition may have a tensile strength of at least 1500 MPa. In another embodiment, the alloy in the as-built condition may have a tensile strength of at least 1600 MPa. In another embodiment, the alloy in the as-built condition may have a tensile strength of 1300 MPa to 2200 MPa. In another embodiment, the alloy in the as-built condition may have a tensile strength of 1600 MPa to 2100 MPa.

[0047] The alloy achieves a combination of high tensile strength and high yield strength. In one embodiment, the yield strength is at least 700 MPa. In another embodiment, the yield strength is at least 900 MPa. In another embodiment, the yield strength of the alloy may be between 700 MPa and 1500 MPa.

[0048] These tensile strengths and yield strengths can also be achieved in conjunction with an elongation of at least 4%. In another embodiment, the elongation can be at least 5%. In another embodiment, the elongation can be between 4% and 20%. In another embodiment, the elongation can be between 4% and 17%.

[0049] In conjunction with the hardness (HRC) of at least 45HRC, this tensile strength, yield strength and elongation can also be achieved. In another embodiment, the hardness can be at least 50HRC. In another embodiment, the hardness can be 45HRC to 58HRC. In another embodiment, it is estimated that the hardness herein can be 50HRC to 58HRC.

[0050] Thus, it will be appreciated that the alloys herein allow for a tensile strength of at least 1300 MPa, a yield strength of at least 700 MPa, an elongation of at least 4%, and a hardness of at least 45 HRC. Other combinations of tensile strength, yield strength, elongation, and hardness of the finished component may be achieved depending on the individual preferred levels of tensile strength, yield strength, elongation, and hardness.

[0051] Table 2 illustrates alloys according to the present invention having high yield strength, tensile strength, and hardness. For example, in one embodiment, a metal component of Alloy A1 has a tensile strength of at least 1400 MPa. The yield strength of Alloy A1 may be at least 1000 MPa. The elongation of Alloy A1 may be at least 10.0%. The hardness of Alloy A1 may be at least 46 HRC. In one embodiment, a metal component of Alloy A2 has a tensile strength of at least 1300 MPa. The yield strength of Alloy A2 may be at least 800 MPa. The elongation of Alloy A2 may be at least 4%. The hardness of Alloy A2 may be at least 46 HRC. In one embodiment, a metal component of Alloy A3 has a tensile strength of at least 1600 MPa. The yield strength of Alloy A3 may be at least 700 MPa. The elongation of Alloy A3 may be at least 6%. The hardness of Alloy A3 may be at least 48 HRC. In one embodiment, a metal component of Alloy A4 has a tensile strength of at least 1700 MPa. The yield strength of Alloy A4 may be at least 700 MPa. The elongation of alloy A4 may be at least 8%.The hardness of alloy A4 may be at least 49 HRC.

[0052] Figure 4The X-ray diffraction (XRD) spectrum of the component made from Alloy A1 shown is evidence of the presence of martensite / ferrite (BCC) and austenite (FCC) phases in the as-built structure. The X-ray diffraction spectrum was collected using a Bruker D5000 X-ray diffractometer and Cu-Kα radiation. Martensite / ferrite and austenite were also observed in micrographs of the microstructure collected by optical microscopy and scanning electron microscopy (SEM), respectively. Figure 2 and Figure 3 This part is constructed using 0.5-1mm layers on a 1018 substrate by using LENS TM The 850-R was built without preheating and has a height of 25mm.

[0053] Figure 5 The equilibrium phase diagram of alloy A1 generated by Thermo-Calc software (Thermo-Calc software, Inc., version 2018b, TCFE9:TCS Steel / Iron Alloy Database, v9). Consistent with the XRD and microscopy data, the phase diagram predicts that the primary phases in the structure are preferably body-centered cubic (BCC) and face-centered cubic (FCC) phases. In addition, several secondary phases are predicted to form during solidification and / or during repeated heating cycles of subsequent and adjacent layer deposition during the printing process. These phases predicted by the phase diagram are various carbides, nitrides, and carbonitrides. The equilibrium phase diagrams generated for alloys A2, A3, and A4 (respectively as shown in Figure 2) are shown in Figure 2. Figure 7 and Figure 8 The primary and secondary phase structures similar to those of alloyed Al are also predicted (as shown in Figure 2). In some cases, similar or different secondary carbides, nitrides, and carbonitrides are present.

[0054] The combination of primary and secondary phases contributes to the high strength, hardness, and ductility (e.g., elongation) measured for alloys A1, A2, A3, and A4 described herein compared to currently available steel alloys for DED processes. These phases are determined by the chemical composition and processing conditions specific to the DED process.

[0055] according to Figure 5 、 Figure 6 、 Figure 7 and Figure 8Based on the equilibrium phase diagrams calculated in

[15] , it is expected that these alloys can be heat treated by conventional quenching and tempering processes to improve and / or modify properties. In the A1, A2, A3, and A4 alloys, heating the alloy to 1000°C or higher, but below the solution temperature, results in the dissolution (molar fraction) of more than 99%, if not all, of the secondary phases, and the formation of an austenitic phase (FCC). During the quenching and tempering process, this is called solutionizing or austenitizing the alloy. After a period of solutionization, the alloy is quenched or rapidly cooled to room temperature to promote the transformation of austenite to martensite and prevent or limit the formation of secondary phases. The alloy is then heated to a temperature between room temperature and the solution temperature to reduce residual stresses and form selected secondary phases and grow these phases to specific sizes to optimize the desired properties, a step called tempering or aging.

[0056] It is further contemplated that these alloys may be subjected to surface treatments such as nitriding, carburizing, and carbonitriding, or may be coated by conventional methods such as physical vapor deposition (PVD), chemical vapor deposition (CVD), and plasma coating. Such processes and methods are commonly used on steel in industry to locally enhance the properties of the steel or surface components to achieve desired properties in a specific application.

[0057] Although exemplary embodiments have been described above, these embodiments are not intended to describe all possible forms of the present invention. On the contrary, the words used in this specification are descriptive words, rather than restrictive words. It should be understood that various changes can be made without departing from the spirit and scope of the present invention. In addition, the features of the various embodiments can be combined into other embodiments of the present invention.

Claims

1. A method for constructing a metal component layer by layer, comprising: An alloy in particulate form is provided, the alloy consisting of: 69.2 wt.% to 89.1 wt.% Fe; 7.25 wt.% to 16.0 wt.% Cr; 0.01 wt.% to 10.0 wt.% Nb; 0.5 wt.% to 4.0 wt.% Mo; 0.03 wt.% to 0.4 wt.% C, and one or more of Ni, Cu, Si, W, Mn, N, and B, wherein: If Ni is present, the Ni content is 1.5 wt.% to 4.0 wt.%; If Cu is present, the Cu content is 0.1 wt.% to 3.0 wt.%; If Si is present, the Si content is 0.1 wt.% to 1.0 wt.%; If W is present, the content of W is 0.1 wt.% to 6.0 wt.%; If Mn is present, the Mn content is 0.4 wt.% to 1.9 wt.%; If N is present, the N content is from 0.03 wt.% to 1.0 wt.%; and If B is present, the content of B is 0.01 wt.% to 0.05 wt.%; providing a substrate; and forming a metal component having one or more layers of the alloy on said substrate by direct energy deposition by melting the alloy to a molten state and cooling and solidifying the alloy; wherein the thickness of each layer of the one or more alloy layers is 20 μm to 2000 μm, The metal component has the following properties: a tensile strength of at least 1300 MPa, a yield strength of at least 700 MPa, an elongation of at least 4.0% and a hardness of at least 45 HRC.

2. The method according to claim 1, wherein The thickness of the layer is from 100 μm to 800 μm.

3. The method according to claim 1, wherein The alloy comprises 82.0 wt. % to 87.0 wt. % Fe; 10.5 to 12.0 wt.% of Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.02 wt.% to 0.05 wt.% Nb; 0.1 wt.% to 0.6 wt.% Cu; 1.2 wt.% to 1.8 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.15 wt.% to 0.22 wt.% C; and 0.03 wt.% to 0.08 wt.% N.

4. The method according to claim 1, wherein The alloy comprises 82.0 wt. % to 87.0 wt. % Fe; 11.0 to 13.5 wt.% Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.02 wt.% to 0.05 wt.% Nb; 0.1 wt.% to 0.4 wt.% Cu; 1.5 wt.% to 2.1 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.17 wt.% to 0.25 wt.% C; and 0.02 wt.% to 0.06 wt.% N.

5. The method according to claim 1, wherein The alloy comprises 79.0 wt.% to 83.0 wt.% Fe; 10.5 to 12.0 wt.% of Cr; 2.8 wt.% to 3.8 wt.% Ni; 0.04 wt.% to 0.08 wt.% Nb; 0.1 wt.% to 0.6 wt.% Cu; 2.5 wt.% to 3.5 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.1 wt.% to 1.0 wt.% W; 0.20 wt.% to 0.25 wt.% of C; and 0.05 wt.% to 0.13 wt.% of N.

6. The method according to claim 1, wherein The alloy comprises 79.0 wt.% to 83.0 wt.% Fe; 7.7 wt.% to 9.0 wt.% Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.04 wt.% to 0.08 wt.% Nb; 1.2 wt.% to 1.8 wt.% Mo; 4.1 wt.% to 5.5 wt.% W; 0.4 wt.% to 1.1 wt.% Mn; 0.15 wt.% to 0.22 wt.% C; 0.05 wt.% to 0.13 wt.% of N; and 0.01 wt.% to 0.05 wt.% of B.

7. The method according to claim 1, wherein The method further includes heating the substrate to a temperature less than or equal to 800° C. before forming the one or more layers of alloy.

8. The method according to claim 1, wherein The metal component is solutionized at a temperature of 900° C. or greater and then quenched.

9. The method according to claim 7, wherein: The method further includes tempering the metal component at a temperature at or above room temperature after forming the metal component.

10. The method according to claim 1, wherein The metal parts undergo processes that change the surface structure and properties including carburizing, nitriding, carbonitriding, and depositing coatings.

11. A printed metal part comprising one or more layers of an iron-based metal alloy, the iron-based metal alloy comprising: 69.2 wt.% to 89.1 wt.% Fe; 7.25 wt.% to 16.0 wt.% Cr; 0.01 wt.% to 10.0 wt.% Nb; 0.5 wt.% to 4.0 wt.% Mo; 0.03 wt.% to 0.4 wt.% C, and one or more of Ni, Cu, Si, W, Mn, N, and B, wherein: If Ni is present, the Ni content is 1.5 wt.% to 4.0 wt.%; If Cu is present, the Cu content is 0.1 wt.% to 3.0 wt.%; If Si is present, the Si content is 0.1 wt.% to 1.0 wt.%; If W is present, the content of W is 0.1 wt.% to 6.0 wt.%; If Mn is present, the Mn content is 0.4 wt.% to 1.9 wt.%; If N is present, the N content is 0.03 wt.% to 1.0 wt.%; If B is present, the content of B is 0.01 wt.% to 0.05 wt.%; wherein the thickness of each layer of the one or more alloy layers is 20 μm to 2000 μm, Among them, the printed metal parts formed by direct energy deposition show a tensile strength of at least 1300 MPa, a yield strength of at least 700 MPa, an elongation of at least 4.0% and a hardness of at least 45 HRC.

12. The printed metal part according to claim 11, wherein: The component comprises one or more layers and has a thickness of 100 μm to 800 μm.

13. The printed metal part according to claim 11, wherein: The alloy comprises 82.0 wt. % to 87.0 wt. % Fe; 10.5 to 12.0 wt.% of Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.02 wt.% to 0.05 wt.% Nb; 0.1 wt.% to 0.6 wt.% Cu; 1.2 wt.% to 1.8 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.15 wt.% to 0.22 wt.% C; and 0.03 wt.% to 0.08 wt.% N.

14. The printed metal part according to claim 13, wherein: The metal component has a tensile strength of at least 1400 MPa, a yield strength of at least 1000 MPa, and an elongation of at least 10.0%.

15. The printed metal part according to claim 11, wherein The alloy comprises 82.0 wt. % to 87.0 wt. % Fe; 11.0 to 13.5 wt.% Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.02 wt.% to 0.05 wt.% Nb; 0.1 wt.% to 0.4 wt.% Cu; 1.5 wt.% to 2.1 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.17 wt.% to 0.25 wt.% C; and 0.02 wt.% to 0.06 wt.% N.

16. The printed metal part according to claim 15, wherein: The metal component has a tensile strength of at least 1300 MPa, a yield strength of at least 800 MPa and a hardness of at least 46 HRC.

17. The printed metal part according to claim 11, wherein: The alloy comprises 79.0 wt.% to 83.0 wt.% Fe; 10.5 to 12.0 wt.% of Cr; 2.8 wt.% to 3.8 wt.% Ni; 0.04 wt.% to 0.08 wt.% Nb; 0.1 wt.% to 0.6 wt.% Cu; 2.5 wt.% to 3.5 wt.% Mo; 0.1 wt.% to 0.5 wt.% Si; 0.1 wt.% to 1.0 wt.% W; 0.20 wt.% to 0.25 wt.% of C; and 0.05 wt.% to 0.13 wt.% of N.

18. The printed metal part according to claim 17, wherein: The metal component has a tensile strength of at least 1600 MPa and a hardness of at least 48 HRC.

19. The printed metal part according to claim 11, wherein The alloy comprises 79.0 wt.% to 83.0 wt.% Fe; 7.7 wt.% to 9.0 wt.% Cr; 1.5 wt.% to 2.5 wt.% Ni; 0.04 wt.% to 0.08 wt.% Nb; 1.2 wt.% to 1.8 wt.% Mo; 4.1 wt.% to 5.5 wt.% W; 0.4 wt.% to 1.1 wt.% Mn; 0.15 wt.% to 0.22 wt.% C; 0.05 wt.% to 0.13 wt.% of N; and 0.01 wt.% to 0.05 wt.% of B.

20. The printed metal part according to claim 19, wherein: The metal component has a tensile strength of at least 1700 MPa and a hardness of at least 49 HRC.

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