WO2023183409A1

WO2023183409A1 - 3d printed die and die holder

Info

Publication number: WO2023183409A1
Application number: PCT/US2023/015938
Authority: WO
Inventors: Bryan Black; Greg Rizzo; Harald LEMKE; Aaron Longstreet; Steven BENEDETTI
Original assignee: Maclean-Fogg Company
Priority date: 2022-03-22
Filing date: 2023-03-22
Publication date: 2023-09-28

Abstract

A 3D printed tool die and tool die kit for a machine is provided. The 3D printed die has a cold-working tool face and having a reduced height being less than a standard tool die. A die holder is configured to be positioned in a standard tool to hold the 3D printed die. A clamp engages and retains the 3D printed die in the die holder.

Description

3D PRINTED DIE AND DIE HOLDER

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63/322,547 filed on March 22, 2022, the disclosure of which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

[0002] This application relates to a metallic tool die formed by additive manufacturing and to the die holder assembly required for holding the 3D printed tool die in a machine.

BACKGROUND

[0003] Thread rolling uses hardened steel dies to displace and mold ductile metals to forms threads into the mirror image of a thread roll die. Thread roll dies are typically machined to produce the thread roll die configuration. The thread roll dies are clamped in a machine to be secured during use but must be able to be easily removed and replaced when the thread roll dies become worn.

SUMMARY

[0004] According to one embodiment of the invention, a tool die is provided with a 3D printed die body having a front cold-working tool face. A retention portion for retaining the die in a tool machine has a complex contour formed on at least one of the back locator face, the top surface or the bottom surface.

[0005] In another embodiment, the 3D printed die body comprises at least one 3D printed thread roll die body and the cold-working tool face comprises front thread face having a thread profile with a plurality of teeth for forming threads. [0006] In another embodiment, a height dimension is defined between the front coldworking tool face and the back locator face, wherein the 3D printed die body has an overall height less than 0.75-inches.

[0007] In another embodiment, the die body has an overall height being approximately 0.5 -inches.

[0008] In another embodiment, the retention portion is formed along at least one of a top surface or a lower surface extending between the front cold-working tool face and the back locator face.

[0009] In another embodiment, the retention portion comprises a groove formed on the top surface and configured to be engaged on a clamp to retain the die in the tool.

[0010] In another embodiment, the groove has a birdsmouth angle.

[0011] In another embodiment, the birdsmouth angle defines an asymmetric groove relative to a top surface, the angle being in the range of 40 to 80 degrees.

[0012] In another embodiment, the birdsmouth angle is in the range of 50 to 70 degrees.

[0013] In another embodiment, the retention portion further comprises a protrusion formed along the bottom surface and adapted for positioning the die in the tool.

[0014] In another embodiment, a height dimension is defined between the front coldworking face and the back locator face, wherein the retention portion has a first height being less than a second height along the die tool.

[0015] In another embodiment, a second 3D printed die body is provided having a second cold-working face, wherein the second die body has a second retention portion cooperating with the first retention portion to retain the second die body relative to the first die body.

[0016] In another embodiment, the die body is formed of a metallic alloy with layer-by- layer deposition, wherein the layers are formed at least in part by powder bed fusion. [0017] In another embodiment, each of the layers has a thickness in the range of 2.0 microns to 200.0 microns.

[0018] In another embodiment, the die body is formed of an iron-based alloy supplied in particle form including the elements C, Cr and Mo, wherein C is present at 0.1 wt. % to 0.35 wt. %, Cr is present at 10.0 wt. % to 19.0 wt. %, Mo is present at 0.5 wt. % to 3.0 wt. %, and at least two elements from Ni, Cu, Nb, Si and N, wherein Ni is present at 0 to 5.0 wt. %, Cu is present at 0 to 5.0 wt. %, Nb is present at 0 to 1.0 wt. %, Si is present at 0 to 1.0 wt. % and N is present at 0 to 0.25 wt. %; the balance of the alloy composition containing Fe.

[0019] In another embodiment, the tool die has a tensile strength of at least 1000 MPa, a yield strength of at least 640 MPa, an elongation of at least 3.0%, and a hardness (HV) of at least 375.

[0020] According to another embodiment, a tool die kit for a machine is provided. The kit has a 3D printed die with a cold-working tool face and having a reduced height being less than a standard tool die. A die holder is configured to be positioned in a standard tool to hold the 3D printed die. A clamp engages and retains the 3D printed die in the die holder.

[0021] In another embodiment, the 3D printed tool die has a retention portion to cooperate with the die holder and clamp to retain the 3D printed tool die in the standard tool pocket of the machine.

[0022] In another embodiment, the retention portion comprises a groove, and wherein the clamp comprises a finger to cooperate and engage the groove.

[0023] In another embodiment, the retention portion comprises a protrusion, wherein the die holder comprises a plate having a locator slot that cooperates with the protrusion to retain and locate the 3D printed die tool in the standard tool pocket of the machine.

[0024] In another embodiment, the die holder comprises a center locator opening defined by a center locator wall and opposing end walls, wherein a back locator face of the 3D printed die abuts the center locator wall, the center locator wall having a thickness to position the cold- working tool surface of the 3D printed tool die in the standard tool.

[0025] In another embodiment, the 3D printed tool die comprises at least one 3D printed thread roll die and the cold-working tool surface comprises a thread profile having a plurality of teeth for forming threads.

[0026] In another embodiment, the kit has a second 3D printed tool die having a second cold-forming tool surface with a second thread profile. A die holder extension is provided align with the die holder and to hold the first and second tool dies is a stacked orientation with the first and second cold-working faces being coplanar.

[0027] In another embodiment, the clamp engages the second 3D printed tool die.

[0028] In another embodiment, at least one die holder shim is provided for stacking on the die holder to accommodate 3D printed dies, wherein a width of the cold-working surfaces varies.

[0029] In another embodiment, the least one die holder shim comprises a plurality of die holder shims for stacking on the die holder to accommodate 3D printed dies having a plurality of widths of the cold-working surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG. 1 illustrates a clamping assembly holding a 3D printed tool die.

[0031] FIG. 2 illustrates a section of a side perspective view of the clamping assembly in

FIG. 1 with the 3D printed tool die.

[0032] FIG. 3 illustrates an exploded view of the clamping assembly with the 3D printed tool die in FIG. 1.

[0033] FIG. 4 illustrates a side view of the clamp of the clamping assembly in FIG. 1.

[0034] FIG. 5 illustrates a side view of a section view through a die holder showing a center locator of the clamping assembly in FIG. 1.

[0035] FIG. 6 illustrates a side view of a section view through the bottom locator in FIG. 1.

[0036] FIG. 7 is a perspective view of the 3D printed tool die according to one embodiment.

[0037] FIG. 8 is a side view of the 3D printed tool die in FIG. 7.

[0038] FIG. 9 illustrates a clamping assembly holding a 3D printed tool die according to another embodiment.

[0039] FIG. 10 illustrates an exploded view of the clamping assembly in FIG. 9 with the 3D printed thread roll die.

[0040] FIG. 11 illustrates a side view of the clamp of the clamping assembly in FIG. 10.

[0041] FIG. 12 illustrates a clamping assembly holding a 3D printed thread roll die according to another embodiment.

[0042] FIG. 13 illustrates an exploded view of the clamping assembly with the 3D printed thread roll die.

[0043] FIG. 14 illustrates a side view of the clamp of the clamping assembly in FIG. 12.

DETAILED DESCRIPTION

[0044] As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.

[0045] This application relates to a metallic tool die formed by an additive manufacturing process by successive, layer-by-layer deposition and selective solidifying of a metallic alloy powder to form the three-dimensional object. These 3D printed roll dies may be printed to have a height that is less than traditional machined thread roll dies. The 3D printed thread roll die, as illustrated in Fig. 1 for example, may be printed using a metallic alloy and process as discussed in U.S. Application No. 17/248,953 filed on February 15, 2021, and U.S. Application No. 16/393,194 filed April 24, 2019 that issued as U.S. Patent No. 10,953,465, and U.S. Application No. 15/800,210 filed November 1, 2017 that issued as U.S. Patent No. 10,920,295, and U.S. Provisional Application No. 62/415,667, filed November 1, 2016, the disclosures of which are hereby incorporated by reference herein. The metallic alloy used for 3D printing the tool die has a higher hardness, such as a hardness (HV) greater than 370 also having high strength and toughness and allows the tool die to have a much lower height.

[0046] One example of an alloy for forming the tool die is an iron-based alloy supplied in particle form including the elements C, Cr and Mo wherein C is present at 0.1 wt. % to 0.35 wt. %, Cr is present at 10.0 wt. % to 19.0 wt. %, Mo is present at 0.5 wt. % to 3.0 wt. % and at least two elements from Ni, Cu, Nb, Si and N, wherein Ni is present at 0 to 5.0 wt. %, Cu is present at 0 to 5.0 wt. %, Nb is present at 0 to 1.0 wt. %, Si is present at 0 to 1.0 wt. % and N is present at 0 to 0.25 wt. %; the balance of the alloy composition containing Fe. Furthermore, the alloy may include some amount of inevitable impurities wherein the level of such impurities may be up to 1.0 wt. %. For example, an element not listed above may also be present at a level of up to 1.0 wt. %, where the corresponding level of Fe can then be reduced by up to 1.0 wt. %. With regards to impurities, it is noted that such is contemplated to include elements such as sulfur, phosphorous and oxygen.

[0047] The tool die has high hardness, high yield and tensile strength, and high elongation as well as low safety (EH&S) and stewardship risk and relatively low cost in both the “as built” and in the “heat treated” state. The tool die formed with the alloy has a tensile strength of at least 1000 MPa, a yield strength of at least 640 MPa, and an elongation of at least 3.0%, hardness (HV) of at least 375. “As-built” refers to the part upon removal from the 3D printing machine, i.e. without any post-build heat treatment. The “heat treated” refers to 3D printed parts that have been subjected to a post-build heat treatment.

[0048] Metal 3D printing processes provide a multitude of exceptional benefits such as the ability to produce highly complex parts with largely reduced part production time. Many 3D printing processes for building metal parts may be used, including processes that utilize solid- liquid-solid phase transformations to build parts. These processes are commonly referred to as powder bed fusion (PBF), selective laser melting (SLM), and electron beam melting (EBM); hereinafter these processes are referred to as PBF.

[0049] The metal alloy may be supplied to the PBF process in powder particle or wire form and is preferably produced using conventional melting with either gas, centrifugal, atomization utilizing gases such as nitrogen or argon gas, or water atomization. Nitrogen gas melting and atomization can be used to increase the nitrogen content in the powder alloy. The powder particles can have a diameter in the range of 1 to 200 microns, more preferably from 3 to 70 microns, and most preferably from 15 to 53 microns.

[0050] Parts may be built with a metal alloy and may use 3D printing machines for PBF such as the SLM®280HL or EOS M-280 and a Trumpf TRUMAFORM LF 250 or other suitable 3D printing machines. The parts may be built in a nitrogen or argon atmosphere. Parts may be built on a metal substrate that is preheated up to 300°C. In addition, no preheating of the substrate can be employed. PBF may utilize one or a plurality of lasers or electron beams with an energy density of 30 J/m³ to 500 J/m³, more preferably in the range of 50 J/m³ to 300 J/m³ and most preferably in the range of 60 J/m ’ to 200 J/m³ or other lasers, electron beams or devices.

[0051] The metal substrate may be formed of an acceptable alloy or material such as stainless steel, e.g. type 304L stainless steel. The process uses a build-up of individual layers each having a thickness typically in the range of 2.0 microns to 200.0 microns. In another embodiment, the individual layers may be in a range of 5.0 microns to 150.0 microns, or in another embodiment in a range of 5.0 microns to 120.0 microns. Accordingly, a suitable range of thickness for the built-up layers is 2.0 microns and higher. In another embodiment, the thickness range for the built-up layers (combination of individual layers) may be from 2 microns to 800 mm and even higher depending upon the capability or requirements of a given printing procedure.

[0052] The 3D printed parts may be heat treated after the parts are built to be able to achieve relatively high hardness, strength, and ductility. Parts produced with PBF may be further enhanced by heat treating to increase the strength and hardness of the parts. It is contemplated that various heat treatments can be performed to affect the part properties and the heat treatment temperatures can be selected from equilibrium phase diagrams. The heat treatment uses (1) high temperature solutionizing (dissolving one or more of the secondary phases), quenching, and tempering (precipitation of the secondary phases) and/or (2) tempering of the as-built part, with each heat-treating step being performed in a vacuum, argon, or nitrogen atmosphere. Solutionizing may be performed at a temperature of greater than 900°C, and for example in the range of 900°C to 1400°C, and tempering is preferably performed at a temperature in the range of 150-900°C. Accordingly, it should be appreciated that with heat treatment the parts may have a tensile strength of at least 1000 MPa, a yield strength of at least 900 MPa, and elongation of at least 1% and a hardness (HV) value of at least 475. Other combinations of tensile strength, yield strength, elongation and hardness may be achieved.

[0053] The present application is directed to a tool die that is 3D printed through an additive manufacturing process. The 3D printed tool die may be a thread-roll die 40, as illustrated in the Figures with a thread pattern, for example. While a planar thread roll die is illustrated, the present application may also be used with a cylindrical thread roll die or other thread roll die. The tool die of the present application may also be any cold-forming die or rolldie such as profde roll-dies, spline-roll dies, or other cold-forming tool dies that may have knurl patterns, annular patterns or other required geometry or patterns.

[0054] The 3D printed dies may have a significantly reduced height compared to standard roll dies. The 3D printed die may be up to 75% thinner than standard tool dies. For example, a #30 thread roll die may have an overall height of approximately 1.5-inches from the thread face to the back surface. In contrast, the 3D printed thread roll die 40, like shown in FIGS. 7-8, may have an overall height H being less than 1.0-inch or even less than 0.75-inches, where the height H is measured from the front face 50 to the back locator face 44. In another embodiment, the overall height H of the 3D printed thread die 40 may be approximately 0.5- inches, where the height may vary slightly based on the thread pitch or cold-working pattern. The reduced height provides material savings and allows the roll die to be printed quicker due to the reduced material. Reduced height may also ensure less warpage of the die during heat treating, if required. Standard machined dies may be approximately 1.5-inches. While standard dies may be re-worked to have a height less than 1.5-inches, standard dies have problems, such as clamping in tools at lower heights such as 0.75-inches.

[0055J The 3D printed roll dies may be used in a standard machine for rolling thread dies. This application also relates to the clamping assembly and kit required for using the 3D printed thread roll die in a traditional tool machine.

[0056] FIGS. 1-6 illustrate a clamping assembly 10 for holding a 3D printed thread roll die 40. The clamping assembly 10 rigidly clamps a thread roll die 40 that is 3D printed while still allowing the 3D printed roll dies to be easily replaced when worn. The clamping assembly 10 may be used with tool dies such as moving or stationary 3D printed thread roll dies, like 3D printed die 40. The clamping assembly 10 fits into a standard die pocket of a machine to properly position the cold-working tool surface of the die 40. As illustrated, the clamping assembly 10 has a clamp 12 and a die holder 14. The clamp 12 clamps along a top surface 42 of the die 40. The base end 18 of die clamps 12 will mount to existing bolt and stud clamps on the machine. The die holder 14 has a center locator opening 24 defined by a center locator wall 26 and opposing end walls 28. The back locator face 44 of the 3D printed die 40 abuts the center locator wall 26. The center locator wall 26 has a thickness T to position the cold-working tool surface of the 3D printed tool die in a standard die pocket of the tool.

[0057] As shown in more detail in FIGS. 7-8, the top surface 42 of the die 40 may have a retention feature 52 for engaging the clamps 12. The top surface 42 may have a retention feature 52 such as groove 54 or a channel. The groove 54 extends along the length of the die 40 on the top surface 42. The groove 54 may be asymmetric relative to the top surface 42 so that when gripped by the clamp 12, the tool die 40 is pulled down and back into the die holder 14.

[0058] The groove 54 may be shaped as a birdsmouth angled groove, as shown in FIG 8. The asymmetric birdsmouth angled groove may be shaped to cooperate with the clamps 12 so that as the clamps 12 are tightened, the die 40 is pulled into engagement with the holder and the back locator face 44 abuts the die holder 14. The birdsmouth angled groove 54 may be asymmetric so that the groove tapers in depth along the height direction across the top surface 42. The clamp 12 may have an angled finger 22 that is angled to grip the groove 54 and act like a ratchet to cinch the tool die 40 into the die holder as the clamp 12 is tightened. The birdsmouth angle 56 may be in the range of 40-degrees to 80-degrees. In another embodiment, the birdsmouth angle 56 is in the range of 50-degrees to 70-degrees. In another embodiment, the birdsmouth angle 56 may be approximately 60-degrees. However, other suitable birdsmouth angles or rachet angles may be possible.

[0059] Typical machined grooves would normally have a regular U-shape being a groove wall. In contrast, the 3D printed thread roll die has a retention feature 54 that has an asymmetric profile or tapered groove. In particular, 3D printing the thread roll die in an upright orientation allows the tapered angle 54 that defines an undercut that could not be 3D printed in a traditional orientation.

[0060] Other retention features may be formed on the top surface 42. For example, the top surface 42 may have a notch, opening, or plurality of notches and/or openings. The retention feature 52 may also be formed as a protrusion or extension extending above the tool face 50.

[0061] The 3D printed tool die 40 may also have a retention feature on the lower locator edge 46 that cooperates with a bottom locator 16 on the die. The lower locator edge 46 may have a concave contour portion and may define a protrusion 60. The lower edge 46 and protrusion may cooperate with a slot 66 on the bottom locator 16 or on the die holder 14. The protrusion 60 of the tool die 40 is anchored in the slot 66 and then as the finger 22 on the clamp engages the birdsmouth angle 54, the tool die 40 is aligned into position so that the cold-working face 50 in the correct position in the tool. The lower edge 46 defines a locator angle 48 that aids in positioning the tool die 40 in the die holder 14 at the correct orientation. The locator angle 48 may be between 5 degrees and 25 degrees. In another embodiment, the locator angle 48 may be 10 to 20 degrees. In a further embodiment, the locator angle 48 may be approximately 15 degrees. However, other locator angles may be possible.

[0062] The bottom locator 16 may be formed as a separate plate, as shown in the exploded view in FIG. 1. Alternatively, the bottom locator portion may be integrally formed with the die holder 14. The die holder 14 may be sized to fit into a standard die pocket for a standard die. For example, the die holder 14 may fit into a standard #30 die pocket of a thread rolling machine, or other standard sized pockets in a machine that uses changeable tool dies. The die holder 14 may also work with standard shimming practices.

[0063] 3D printing the tool die 40 layer-by-layer allows unique geometry that cannot be achieved with typical machined tool dies. In particular, the thread-roll die may be 3D printed in an upright orientation, where layers of the metallic alloy are added in the upright direction that is transverse to the cold-working tool surface, such as the thread-rolling surface. Traditional machining methods and even traditional additive manufacturing methods approach the manufacturing of the tool from a completely different direction. Even tools formed by additive manufacturing are normally formed with layers added in a height direction H so that the layers are added in the largest surface defined by the width W and longitudinal length L of the tool die 40 and require the least amount of layers to achieve the desired height H. As shown in the drawings, width W corresponds to the X-direction, longitudinal length corresponds to the Y- direction, and height H corresponds to the Z-direction.

[0064] The upright direction 20 is generally parallel to the longitudinal direction of the threads and while the upright direction may be generally parallel to a vertical direction, the upright direction may also vary from the vertical direction. In one embodiment, the upright direction varies from the vertical direction by +/- 45 degrees. In another embodiment, the upright direction varies from a vertical direction by +/- 10 degrees. In a further embodiment, the upright direction varies from a vertical direction by +/- 5 degrees. A greater angle, such as 45 degrees, allows that part to be printed faster, but may need more support structure and may also have more layer lines. A lesser angle, such as 5 to 10 degrees may be printed more slowly but may provide the part with better surface roughness and better resolution, such as better resolution of the thread features.

[0065] In the present application, the additive manufacturing method may add layers in generally the upright direction 20. Layers are added in the upright direction 20 on the smallest surface defined by the width W and height H of the tool die 40. While 3D printing the tool die 40 in the upright direction takes more time, it allows more complex geometries to be formed along the tool die 40. In particular, 3D printing the tool die in the upright direction may allow for the retention feature 52 having complex geometry or irregular shape. A tool feature with an irregular shape has sides and angles of different lengths and sizes. For example, the tool features may be an irregular shape having multiple curvatures, multiple planes or asymmetric geometry or with dimensions that vary in at least two directions of the width direction, height direction or the longitudinal direction. The tool features may also have a complex geometry with three- dimensional designs and may also include undercuts, hollow structures, or intricate internal shapes that would require multiple steps using traditional manufacturing methods. 3D printing in the upright direction allows for these irregular or complex geometries, such as undercut features that have increasing dimensions in the height direction that are not achievable with traditional machining or even with traditional 3D printing directions. In another example, 3D printing may allow adjacent thread teeth to have different tool features or features formed at different locations than the adjacent thread teeth. Additionally, printing in the upright direction may also define a smoother surface finish on the tool surface than printing the in a horizontal direction. The thread face 50 may include thread die features as described in U.S. Provisional Application No. 63/301,024 filed January 19, 2022, and International Application No. PCT/US2023/11145 filed January 19, 2023, the disclosures of which are hereby incorporated by reference herein.

[0066] In another embodiment, the 3D printed dies may have other retention features, such as a U-shaped cross-section in the height direction where the back locator face has a concave grip feature to cooperate with a corresponding die shoe that retains the die in the die pocket of the machine. In another embodiment, the 3D printed roll die may have reduced material on the back locator face. The back locator face may have a lattice design, or other pattern or configuration that saves material in the height direction. [0067] FIGS. 9-11 illustrate a clamping assembly 100 with the 3D printed thread roll die 140 where the clamping assembly includes an extension shim 110 for stacking on the die holder 14 in order to accommodate different sized 3D printed dies. For example, a standard thread roll die may have a thread face 50 being approximately 1-inch. The spacer extension 110 allows wider dies to be used with the die holder 14. Wider dies may have a width of 1.25-inches up to 2.5-inches, or possibly wider. A clamping assembly kit 100 may have a plurality of spacer extensions 110 that may be stacked to accommodate numerous different width dies 140. Alternatively, the clamping assembly kit 100 may have a plurality of different sized extensions to accommodate numerous different widths dies 140.

[0068] FIGS. 12-14 illustrate a clamping assembly 200 for holding stacked 3D printed thread roll dies. The assembly 200 has a bottom tool die 240 and a top tool die 244. A die holder extension 210 holds the first tool die 240 and the second tool die 244 in a stacked orientation so that a first cold-working face 50 is generally coplanar to the second cold-working face 250. Having two tool dies 240, 244 allows double ended bolts to be formed. Doubled ended bolts may have the same thread profile. However, the first and second tool dies 240, 244 may also have two different thread profiles.

[0069] The second die body 244 has a second retention portion 252 that is shaped to cooperate with the first retention portion 52 to retain and lock the second die body 244 relative to the first die body 240. The second 3D printed tool die 244 may also have a retention feature on the upper surface that cooperates with a top locator plate 214. The second tool die 244 may also have a projection 270 along the top surface 242. The top surface 242 and protrusion 70 may cooperate with an upper slot 266 on the top locator plate 214.

[0070] While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.

Claims

WHAT IS CLAIMED IS:

1. A tool die comprising: a 3D printed die body having: a front cold-working tool face; a back locator face; a top surface and a bottom surface; and a retention portion for retaining the die in a machine, wherein therein the retention portion has a complex contour formed on at least one of the back locator face, the top surface or the bottom surface.

2. The tool die of claim 1, wherein the 3D printed die body comprises at least one 3D printed thread roll die body and the cold-working tool face comprises front thread face having a thread profile with a plurality of teeth for forming threads.

3. The tool die of claim 2, wherein a height dimension is defined between the front cold-working tool face and the back locator face, wherein the 3D printed die body has an overall height less than 0.75-inches.

4. The tool die of claim 3, wherein the die body has an overall height being approximately 0.5-inches.

5. The tool die of claim 1, wherein the retention portion is formed along at least one of a top surface or a lower surface extending between the front cold-working tool face and the back locator face.

6. The tool die of claim 5, wherein the retention portion comprises a groove formed on the top surface and configured to be engaged on a clamp to retain the die in the machine.

7. The tool die of claim 6, wherein the groove has a birdsmouth angle.

8. The tool die of claim 7, wherein the birdsmouth angle defines an asymmetric groove relative to a top surface, the angle being in the range of 40 to 80 degrees.

9. The tool die of claim 8, wherein the birdsmouth angle is in the range of 50 to 70 degrees.

10. The tool die of claim 6, wherein the retention portion further comprises a protrusion formed along the bottom surface and adapted for positioning the die in the machine.

11. The tool die of claim 1, wherein a height dimension is defined between the front cold-working face and the back locator face, wherein the retention portion has a first height being less than a second height along the die tool.

12. The tool die of claim 1, further comprising a second 3D printed die body having a second cold-working face, wherein the second die body has a second retention portion cooperating with the first retention portion to retain the second die body relative to the first die body.

13. The tool die of claim 1, wherein the die body is formed of a metallic alloy with layer-by-layer deposition, wherein the layers are formed at least in part by powder bed fusion.

14. The tool die of claim 13, wherein each of the layers has a thickness in the range of 2.0 microns to 200.0 microns.

15. The tool die of claim 1, wherein the die body is formed of an iron-based alloy supplied in particle form including the elements C, Cr and Mo, wherein C is present at 0.1 wt. % to 0.35 wt. %, Cr is present at 10.0 wt. % to 19.0 wt. %, Mo is present at 0.5 wt. % to 3.0 wt. %, and at least two elements from Ni, Cu, Nb, Si and N, wherein Ni is present at 0 to 5.0 wt. %, Cu is present at 0 to 5.0 wt. %, Nb is present at 0 to 1.0 wt. %, Si is present at 0 to 1.0 wt. % and N is present at 0 to 0.25 wt. %; the balance of the alloy composition containing Fe.

16. The tool die of claim 1, wherein the tool die has a tensile strength of at least 1000 MPa, a yield strength of at least 640 MPa, an elongation of at least 3.0%, and a hardness (HV) of at least 375.

17. A tool die assembly comprising: a die holder to hold the 3D printed tool die of claim 1, the die holder configured to be positioned in a standard tool pocket of a machine; and a clamp to engage the retention portion and retain the die tool in the die holder.

18. A tool die kit comprising: a 3D printed die with a cold-working tool face and having a reduced height being less than a standard tool die; a die holder configured to be positioned in a standard tool to hold the 3D printed die; and a clamp to engage and retain the 3D printed die in the die holder.

19. The kit of claim 18, wherein the 3D printed tool die has a retention portion to cooperate with the die holder and clamp to retain the 3D printed tool die in the standard tool pocket.

20. The kit of claim 19, wherein the retention portion comprises a groove, and wherein the clamp comprises a finger to cooperate and engage the groove.

21. The kit of claim 19, wherein the retention portion comprises a protrusion, wherein the die holder comprises a plate having a locator slot that cooperates with the protrusion to retain and locate the 3D printed die tool in the standard tool pocket.

22. The kit of claim 18, wherein the die holder comprises a center locator opening defined by a center locator wall and opposing end walls, wherein a back locator face of the 3D printed die abuts the center locator wall, the center locator wall having a thickness to position the cold-working tool surface of the 3D printed tool die in the standard tool pocket.

23. The kit of claim 18, wherein the 3D printed tool die comprises at least one 3D printed thread roll die and the cold-working tool surface comprises a thread profile having a plurality of teeth for forming threads.

24. The kit of claim 18, further comprising: a second 3D printed tool die having a second cold-forming tool surface with a second thread profile; and a die holder extension to hold the first and second tool dies is a stacked orientation with the first and second cold-working faces being coplanar.

25. The kit of claim 24, wherein the clamp engages the second 3D printed tool die.

26. The kit of claim 18, further comprising: at least one die holder shim for stacking on the die holder to accommodate 3D printed dies, wherein a width of the cold-working surfaces varies.

27. The kit of claim 26, wherein the least one die holder shim comprises a plurality of die holder shims for stacking on the die holder to accommodate 3D printed dies having a plurality of widths of the cold-working surfaces.