HIGH HARDNESS AND TEMPERATURE-RESISTANT ALLOY AND ARTICLE COMPRISING THE SAME

Abstract

A high hardness and temperature-resistant alloy is disclosed, and comprises 10-40 atomic percent Co, 30-56 atomic percent Cr, 10-40 atomic percent Ni, 6-13 atomic percent C, 0-8 atomic percent Mo, and 0-8 atomic percent W. Moreover, the elemental composition of the high hardness and temperature-resistant alloy can further comprise at least one additive element, such as Pb, Sn, Ge, Si, Zn, Sb, P, B, Mg, Mn, V, Nb, Ti, Zr, Y, La, Ce, Al, Ta, Cu, and Fe. Experimental data reveal that, the high hardness and temperature-resistant alloy can still show a property of hardness greater than HV100 in 900 degrees Celsius. Therefore, experimental data have proved that the high hardness and temperature-resistant alloy has a significant potential for applications in the manufacture of hot working die metals, components (e.g., turbine blade) for high temperature applications, and devices (e.g., aeroengine) for high temperature applications.

Claims

1. A high hardness and temperature-resistant alloy, having a specific property of hardness greater than HV100 in 900 degrees Celsius and having an elemental composition of Co.sub.wCr.sub.xNi.sub.yC.sub.zMo.sub.mW.sub.n; wherein w, x, y, z, m, and n are numeric values of Co, Cr, Ni, C, Mo, and W in atomic percent, respectively; and wherein w, x, y, z, m, and n satisfy 10≤w≤40, 30≤x≤56, 10≤y≤40, 6≤z≤13, m≤8, and n≤8.

2. The high hardness and temperature-resistant alloy of claim 1, being produced by using a manufacturing method selected from a group consisting of: vacuum arc melting process, electric resistance wire heating process, electric induction heating process, rapid solidification process, mechanical alloying process, and powder metallurgical process.

3. The high hardness and temperature-resistant alloy of claim 1, wherein the high hardness and temperature-resistant alloy is processed to be an article selected from a group consisting of powder article, wire article, welding rod, flux cored wire, plate article, and bulk article.

4. The high hardness and temperature-resistant alloy of claim 1, wherein the high hardness and temperature-resistant alloy is disposed on a surface of a work piece by using a process selected from a group consisting of casting process, electric-arc welding process, laser welding process, plasma-arc welding process, thermal spraying process, thermal sintering process, 3D additive manufacturing process, mechanical process, and chemical process.

5. The high hardness and temperature-resistant alloy of claim 1, wherein the high hardness and temperature-resistant alloy is processed to be in an as-cast state or a homogenization state.

6. An article, being made of a high hardness and temperature-resistant alloy material having an elemental composition of Co.sub.wCr.sub.xNi.sub.yC.sub.zMo.sub.mW.sub.n; wherein w, x, y, z, m, and n are numeric values of Co, Cr, Ni, C, Mo, and W in atomic percent, respectively; wherein w, x, y, z, m, and n satisfy 10≤w≤40, 30≤x≤56, 10≤y≤40, 6≤z≤13, m≤8, and n≤8; and wherein the article is selected from a group consisting of hot work tool, component for high temperature application, and device for high temperature application.

7. A high hardness and temperature-resistant alloy, having a specific property of hardness greater than HV100 in 900 degrees Celsius and having an elemental composition of Co.sub.wCr.sub.xNi.sub.yC.sub.zMo.sub.mW.sub.nM.sub.s; wherein M represents at least one additive element that is selected from a group consisting of Pb, Sn, Ge, Si, Zn, Sb, P, B, Mg, Mn, V, Nb, Ti, Zr, Y, La, Ce, Al, Ta, Cu, Fe; wherein w, x, y, z, m, n, and s are numeric values of Co, Cr, Ni, C, Mo, W, and M in atomic percent, respectively; and wherein w, x, y, z, m, n, and s satisfy 10≤w≤40, 30≤x≤56, 10≤y≤40, 6≤z≤13, m≤8, n≤8, and s≤10.

8. The high hardness and temperature-resistant alloy of claim 7, being produced by using a manufacturing method selected from a group consisting of: vacuum arc melting process, electric resistance wire heating process, electric induction heating process, rapid solidification process, mechanical alloying process, and powder metallurgical process.

8. The high hardness and temperature-resistant alloy of claim 7, wherein the high strength and low modulus alloy is processed to be an article selected from a group consisting of powder article, wire article, welding rod, flux cored wire, plate article, and bulk article.

9. The high hardness and temperature-resistant alloy of claim 7, wherein the high hardness and temperature-resistant alloy is disposed on a surface of a work piece by using a process selected from a group consisting of casting process, electric-arc welding process, laser welding process, plasma-arc welding process, thermal spraying process, thermal sintering process, 3D additive manufacturing process, mechanical process, and chemical process.

10. The high hardness and temperature-resistant alloy of claim 7, wherein the high hardness and temperature-resistant alloy is processed to be in an as-cast state or a homogenization state.

11. An article, being made of a high hardness and temperature-resistant alloy material having an elemental composition of Co.sub.wCr.sub.xNi.sub.yC.sub.zMo.sub.mW.sub.nM.sub.s; wherein M represents at least one additive element that is selected from a group consisting of Pb, Sn, Ge, Si, Zn, Sb, P, B, Mg, Mn, V, Nb, Ti, Zr, Y, La, Ce, Al, Ta, Cu, Fe; wherein w, x, y, z, m, n, and s are numeric values of Co, Cr, Ni, C, Mo, W, and M in atomic percent, respectively; wherein w, x, y, z, m, n, and s satisfy 10≤w≤40, 30≤x≤56, 10≤y≤40, 6≤z≤13, m≤8, n≤8, and s≤10; and wherein the article is selected from a group consisting of hot work tool, component for high temperature application, and device for high temperature application.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The invention as well as a preferred mode of use and advantages thereof will be best understood by referring to the following detailed descriptions of an illustrative embodiment in conjunction with the accompanying drawings, wherein:

[0023] FIG. 1A shows an image of a hot extrusion mold made of SKD61 steel before use;

[0024] FIG. 1B shows an image of the hot extrusion mold made of SKD61 steel after use;

[0025] FIG. 2A shows an image of a hot extrusion mold made of a high hardness and temperature-resistant alloy before use; and

[0026] FIG. 2B shows an image of the hot extrusion mold made of a high hardness and temperature-resistant alloy after use.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] To more clearly describe a high hardness and temperature-resistant alloy and an article comprising the same, embodiments of the present invention will be described in detail with reference to the attached drawings hereinafter.

First Embodiment

[0028] In the first embodiment, the high hardness and temperature-resistant alloy is designed to have an elemental composition of Co.sub.wCr.sub.xNi.sub.yC.sub.zMo.sub.mW.sub.n, so as to exhibit a specific property of hardness greater than HV100 in 900 degrees Celsius. As described in more detail below, w, x, y, z, m, and n are numeric values of Co, Cr, Ni, C, Mo, and W in atomic percent, respectively. Moreover, w, x, y, z, m, and n satisfy 10≤w≤40, 30≤x≤56, 10≤y≤40, 6≤z≤13, m≤8, and n≤8. For example, the high hardness and temperature-resistant alloy is designed to comprise: 40 at % Co, 30 at % Cr, 18 at % Ni, 6 at % C, 3 at % Mo, and 3 at % W. In such case, the high hardness and temperature-resistant alloy has an elemental composition of Co.sub.40Cr.sub.30Ni.sub.18C.sub.6Mo.sub.3W.sub.3. That is, w=40, x=30, y=18, z=6, m=3, and n=3.

Second Embodiment

[0029] In the second embodiment, the high hardness and temperature-resistant alloy is designed to have an elemental composition of Co.sub.wCr.sub.xNi.sub.yC.sub.zMo.sub.mW.sub.nM.sub.s, so as to exhibit a specific property of hardness greater than HV100 in 900 degrees Celsius. As described in more detail below, M represents at least one additive element that is selected from a group consisting of Pb, Sn, Ge, Si, Zn, Sb, P, B, Mg, Mn, V, Nb, Ti, Zr, Y, La, Ce, Al, Ta, Cu, Fe. On the other hand, w, x, y, z, m, n, and s are numeric values of Co, Cr, Ni, C, Mo, W, and M in atomic percent, respectively. Moreover, w, x, y, z, m, n, and s satisfy 10≤w≤40, 30≤x≤56, 10≤y≤40, 6≤z≤13, m≤8, n≤8, and s≤10. For example, the high hardness and temperature-resistant alloy is designed to comprise: 40 at % Co, 30 at % Cr, 15 at % Ni, 6 at % C, 3 at % Mo, 3 at % W, and 3 at % Nb. In such case, the high hardness and temperature-resistant alloy has an elemental composition of Co.sub.40Cr.sub.30Ni.sub.15C.sub.6Mo.sub.3W.sub.3Nb.sub.3. That is, w=40, x=30, y=15, z=6, m=3, n=3, and s=3.

[0030] In other words, the high hardness and temperature-resistant alloy comprises principal elements of Co, Cr, and Ni and at least one additive element. The most important thing is that, content of Co in the high hardness and temperature-resistant alloy of the present invention is significantly less than that in the conventional cobalt-based superalloy. In the high hardness and temperature-resistant alloy of the present invention, Co, Cr and Ni construct the base phase that is a face centered cubic (FCC) structure. Moreover, in practical applications, the high hardness and temperature-resistant alloy can be processed to be an article selected from a group consisting of powder article, wire article, welding rod, flux cored wire, plate article, and bulk article.

[0031] Therefore, engineers skilled in the development and manufacture of alloys are certainly able to fabricate a specific article comprising the high hardness and temperature-resistant alloy according to the present invention, such as hot work tools (e.g., hot extrusion mold), components for high temperature applications (e.g., turbine blade), and devices for high temperature applications (e.g., aeroengine). In other words, compared to the conventional cobalt-based superalloys, the low cobalt content, high hardness and temperature-resistant alloy of the present invention can be fabricated with a low-cost and easy-to-obtain alloy composition, and thereby be applied to technology fields of aerospace industry, energy industry, chemical industry, etc.

[0032] As explained in more detail below, method for making the high hardness and temperature-resistant alloy is selected from a group consisting of: vacuum arc melting process, electric resistance wire heating process, electric induction heating process, rapid solidification process, mechanical alloying process, and powder metallurgical process. On the other hand, the high hardness and temperature-resistant alloy can be processed so as to be disposed on a surface of a work piece, and the processing method is selected from a group consisting of casting process, electric-arc welding process, laser welding process, plasma-arc welding process, thermal spraying process, thermal sintering process, 3D additive manufacturing process, mechanical process, and chemical process.

[0033] It is worth mentioning that, inventors of the present invention have completed experiments in order to prove that the high hardness and temperature-resistant alloy of the present invention can indeed be made.

[0034] First Experiment

[0035] In the first experiment, 10 samples of the high hardness and temperature-resistant alloy according to the present invention are fabricated by vacuum arc melting process. The following table (2) lists each sample's elemental composition. Moreover, homogenization process, hardness measurement, and microstructure analysis for the 10 samples are also completed, and related measurement data are recorded in the following table (2) as well.

TABLE-US-00002 TABLE (2) Hardness (HV) High hardness and As-cast temperature-resistant alloy state Samples Elemental composition (RT) 900° C. No. 1 Co.sub.40Cr.sub.30Ni1.sub.8C.sub.6Mo.sub.3W.sub.3 418.5 268.7 No. 2 Co.sub.40Cr.sub.30Ni.sub.15C.sub.6Mo.sub.3W.sub.3Nb.sub.3 428.6 281.1 No. 3 Co.sub.40Cr.sub.30Ni.sub.15C.sub.6Mo.sub.3W.sub.3Fe.sub.3 411.3 263.2 No. 4 Co.sub.40Cr.sub.30Ni.sub.15C.sub.6Mo.sub.3W.sub.3Mn.sub.3 413.2 264.1 No. 5 Co.sub.40Cr.sub.33Ni.sub.12C.sub.6Mo.sub.3W.sub.3Ta.sub.3 433.6 287.5 No. 6 Co.sub.38Cr.sub.33Ni.sub.14C.sub.6Mo.sub.3W.sub.3P.sub.3 425.3 275.4 No. 7 Co.sub.38Cr.sub.33Ni.sub.17C.sub.6Mo.sub.2W.sub.2Zr.sub.2 432.1 286.3 No. 8 Co.sub.38Cr.sub.30Ni.sub.15C.sub.6Mo.sub.3W.sub.3V.sub.3Ti.sub.2 422.3 275.5 No. 9 Co.sub.38Cr.sub.30Ni.sub.15C.sub.6Mo.sub.3W.sub.1Zn.sub.3Pb.sub.2B.sub.2 431.2 281.1 No. 10 Co.sub.38Cr.sub.30Ni.sub.15C.sub.6Mo.sub.3W.sub.1Sb.sub.3Si.sub.2Y.sub.2 428.9 277.8

[0036] From the forgoing table (2), it is easy to find that, the 10 samples have included the first embodiment and the second embodiment of the high hardness and temperature-resistant alloy. The most important thing is that, the high hardness and temperature-resistant alloy of the present invention can be processed to be in an as-cast state or a homogenization state, and shows a specific property of hardness greater than HV250 in 900 degrees Celsius. Moreover, experimental data have also revealed that, the 10 samples of the high hardness and temperature-resistant alloy all exhibit hardness greater than HV400.

[0037] Second Experiment

[0038] In the second experiment, 20 samples of the high hardness and temperature-resistant alloy according to the present invention are fabricated by vacuum arc melting process. The following tables (3) and (4) list each sample's elemental composition. Moreover, homogenization process, hardness measurement, and microstructure analysis for the 20 samples are also completed, and related measurement data are recorded in the following table (3) and (4).

TABLE-US-00003 TABLE (3) Hardness (HV) High hardness and As-cast temperature-resistant alloy state Samples Elemental composition (RT) 900° C. No. 11 Co.sub.25Cr.sub.45Ni.sub.15C.sub.6Mo.sub.1W.sub.8 587.2 395.3 No. 12 Co.sub.25Cr.sub.40Ni.sub.15C.sub.6Mo.sub.3W.sub.8Sn.sub.3 593.1 398.8 No. 13 Co.sub.25Cr.sub.40Ni.sub.15C.sub.8Mo.sub.3W.sub.3Zr.sub.3Ti.sub.3 631.6 423.1 No. 14 Co.sub.25Cr.sub.40Ni.sub.15C.sub.8Mo.sub.3W.sub.3Ge.sub.3Sb.sub.3 625.1 425.3 No. 15 Co.sub.25Cr.sub.37Ni.sub.15C.sub.8Mo.sub.3W.sub.3Al.sub.3Mg.sub.3B.sub.3 621.8 416.3 No. 16 Co.sub.20Cr.sub.50Ni.sub.10C.sub.9Mo.sub.8W.sub.3 663.7 455.7 No. 17 Co.sub.20Cr.sub.42Ni.sub.22C.sub.13W.sub.3 448.3 296.1 No. 18 Co.sub.20Cr.sub.45Ni.sub.25C.sub.7Mo.sub.3 664.5 431.3 No. 19 Co.sub.20Cr.sub.45Ni.sub.20C.sub.6Mo.sub.1W.sub.1Si.sub.7 675.4 461.8 No. 20 Co.sub.20Cr.sub.37Ni.sub.22C.sub.8Mo.sub.5W.sub.2Ge.sub.3Pb.sub.3 694.6 479.3

TABLE-US-00004 TABLE (4) Hardness (HV) High hardness and As-cast temperature-resistant alloy state Samples Elemental composition (RT) 900° C. No. 11 Co.sub.15Cr.sub.27Ni.sub.40C.sub.6Mo.sub.6W.sub.6 731.2 477.6 No. 12 Co.sub.15Cr.sub.30Ni38C6Mo3W3Al5 758.3 482.1 No. 13 Co.sub.15Cr.sub.30Ni.sub.33C.sub.10Mo.sub.3W.sub.3Mg.sub.3La.sub.3 713.3 450.3 No. 14 Co.sub.15Cr.sub.36Ni.sub.33C.sub.6Mo.sub.3W.sub.3Mn.sub.2Fe.sub.2 729.3 456.2 No. 15 Co.sub.15Cr.sub.30Ni.sub.33C.sub.8Mo.sub.3W.sub.3Ti.sub.3Zn.sub.3Y.sub.3 720.8 451.1 No. 16 Co.sub.10Cr.sub.56Ni.sub.20C.sub.9Mo.sub.2W.sub.3 865.3 512.7 No. 17 Co.sub.10Cr.sub.56Ni.sub.15C.sub.6Mo.sub.6W.sub.1Zr.sub.6 833.2 498.8 No. 18 Co.sub.10Cr.sub.50Ni.sub.17C.sub.11Mo.sub.2W.sub.4Sn.sub.3Cu.sub.3 850.7 501.3 No. 19 Co.sub.10Cr.sub.37Ni.sub.20C.sub.13Mo.sub.6W.sub.8Nb.sub.3Ce.sub.3 583.2 388.1 No. 20 Co.sub.10Cr.sub.50Ni.sub.15C.sub.9Mo.sub.4W.sub.5Zr.sub.3V.sub.3B.sub.1 858.7 506.3

[0039] From the forgoing table (3) and (4), it is understood that, the 20 samples of the high hardness and temperature-resistant alloy all include a specific property of hardness greater than HV250 in 900 degrees Celsius. Moreover, experimental data have also revealed that, the 20 samples of the high hardness and temperature-resistant alloy all exhibit hardness greater than HV500. On the other hand, sample No. 9 and No. 20 also exhibit outstanding lubricity and low friction coefficient because of the addition of element Pb. Moreover, sample No. 15 and No. 22 also exhibit excellent oxidation resistance because of the addition of element Al.

[0040] Herein, it is worth mentioning that, because of the high content of Cr and Ni, the high hardness and temperature-resistant alloy of the present invention exhibits more outstanding high-temperature corrosion resistance than the conventional cobalt-based superalloy. Therefore, the high hardness and temperature-resistant alloy of the present invention is suitable for being applied to technology fields of aerospace industry, energy industry, chemical industry, etc.

[0041] Third Experiment

[0042] Nowadays, linear slide rail is commonly made of carbon steel or alloy steel by using a hot extrusion equipment including a hot extrusion mold. In which, the hot extrusion mold is commonly made of SKD 61 steel. In the third experiment, the high hardness and temperature-resistant alloy of the present invention is processed to be a hot extrusion mold. Then, one hot extrusion mold made of SKD 61 steel and the other hot extrusion mold made of the high hardness and temperature-resistant alloy of the present invention are used in the manufacture of linear slide rails, separately.

[0043] FIG. 1A shows an image of a hot extrusion mold made of SKD61 steel before use, and FIG. 1B shows an image of the hot extrusion mold made of SKD61 steel after use. On the other hand, FIG. 2A shows an image of a hot extrusion mold made of the high hardness and temperature-resistant alloy before use, and FIG. 2B shows an image of the hot extrusion mold made of the high hardness and temperature-resistant alloy after use. From FIG. 1A and FIG. 1B, it is observed that, after the hot extrusion mold made of SKD61 steel is used to complete the manufacture of a linear slide rail, distortion and damages occur around the die orifice of the hot extrusion mold made of SKD61 steel. However, FIG. 2A and FIG. 2B reveal that, after the hot extrusion mold made of the high hardness and temperature-resistant is used to complete the manufacture of a linear slide rail, the integrity of the die orifice of the hot extrusion mold made of the high hardness and temperature-resistant remains unchanged. As a result, experimental data have proved that, the high hardness and temperature-resistant alloy of the present invention can be applied in the manufacture of a hot work tool (e.g., hot extrusion mold) instead of the conventional SKD61 steel.

[0044] Therefore, through above descriptions, all embodiments and their experimental data of the high hardness and temperature-resistant alloy according to the present invention have been introduced completely and clearly; in summary, the present invention includes the advantages of:

[0045] (1) The present invention discloses a high hardness and temperature-resistant alloy comprising 10-40 atomic percent Co, 30-56 atomic percent Cr, 10-40 atomic percent Ni, 6-13 atomic percent C, 0-8 atomic percent Mo, and 0-8 atomic percent W. Moreover, the elemental composition of the high hardness and temperature-resistant alloy can further comprise at least one additive element, such as Pb, Sn, Ge, Si, Zn, Sb, P, B, Mg, Mn, V, Nb, Ti, Zr, Y, La, Ce, Al, Ta, Cu, and Fe. Experimental data reveal that, the high hardness and temperature-resistant alloy can still show a property of hardness greater than HV100 in 900 degrees Celsius. According to the experimental data, it is believed that the high hardness and temperature-resistant alloy of the present invention has a significant potential for applications in the manufacture of hot working tools, components (e.g., turbine blade) for high temperature applications, and devices (e.g., aeroengine) for high temperature applications.

[0046] The above descriptions are made on embodiments of the present invention. However, the embodiments are not intended to limit the scope of the present invention, and all equivalent implementations or alterations within the spirit of the present invention still fall within the scope of the present invention.