CHROME-FREE AND LOW-CHROME WEAR-RESISTANT ALLOYS

Description

BACKGROUNDField

[0001] Embodiments of the disclosure relate generally to iron alloys having low or no chromium content.Description of the Related Art

[0002] Abrasive and erosive wear is a major concern for operators in applications that involve sand, rock, or other hard media wearing away against a surface. Applications which see severe wear typically utilize materials of high hardness to resist material failure due to the severe wear. These materials typically contain carbides and / or borides as hard precipitates which resist abrasion and increase the bulk hardness of the material. These materials are often applied as a coating, known as hardfacing, through various welding processes or cast directly into a part.

[0003] The most commonly used wear resistant ferrous materials for casting and hardfacing contain chromium as an alloying addition. Chromium as an alloying element typically serves two purposes, improving hardenability and forming chromium containing carbides, borides, and / or borocarbides. Both these purposes improve the wear performance of the material. However, when an alloy containing chromium is cast or welded, carcinogenic hexavalent chromium fumes are released. The amount of chromium released is a largely function of the chromium content of the alloy with increasing chromium levels resulting in greater release. Hexavalent chromium levels released from these alloys commonly exceed standards, proposed standards, and guidelines set by OSHA, NIOSH, CARB, and other regulatory bodies. In areas that manufacture chromium bearing alloys, chromium levels frequently exceed EPA specified maximums. Recently, even lower acceptable safe levels have been proposed and new materials are needed that facilitate compliance with current and future laws and regulations.

[0004] U.S. Patent Nos. 8,474,541 and 6,702,905 teach a chromium bearing Fe-based alloy which forms transition metal borides.

[0005] There have been some specific attempts at developing chromium free and wear resistant ferrous alloys. For example, U.S. Pub. No. 2013 / 0294962 ("Wallindescribes a chromium free hardfacing consumable. The wear resistance of the alloys described in the application comes from a combination of niobium or titanium carbides and borides or borocarbides of which the metallic constituent comprises mostly iron.

[0006] Similarly, U.S. Pat. Nos. 7,569,286, 8,268,453, 4,673,550, 4,419,130 teach alloys, including chromium free alloys that rely on borides substantially for their wear resistance. These borides comprise predominantly Fe and Ti based borides.

[0007] U.S. Pat. No. 4,235,630 ("Babu") teaches a wear resistant alloy comprising a mixture of ferroboron and molybdenum. Babu teaches a volume and mole fraction of borides that exceeds the criteria described in this disclosure. Further Babu describes alloys where the matrix comprises substantial amounts of eutectic Fe-Mo intermetallics or iron borides.

[0008] WO 2016 / 014665 relates to an alloy comprising in the broadest sense 0.2 to 4.0 wt.-% B and 0.2 to 5.0 wt.-% C, at least another element and the rest iron. Exemplary alloys comprise chromium in the amounts of 2 to 15 wt.-%. EP 3 034 211 relates to an alloy comprising in the broadest embodiment 0.2 to 1.5 wt.-% C. JP H07 179997 relates to an alloy comprising 7.0 to 50 wt.-% Co and 0.5 to 2.9 wt.-% Cr. US 4,966,626 relates to an alloy comprising 2 to 10 wt.-% Cr. JP S63 65056 to an alloy comprising 1 to 2 wt.-% Mo and 2 to 10 wt.-% Cr.SUMMARY

[0009] The invention is as set forth in the appended claims. Embodiments of the present application include hardfacing / hardbanding materials, alloy or powder compositions used to make such hardfacing / hardbanding materials, methods of forming the hardfacing / hardbanding materials, and the components or substrates incorporating or protected by these hardfacing / hardbanding materials.

[0010] Disclosed herein are embodiments of a low chromium or chromiumfree ferrous alloy, wherein the alloy is formed into or configured to form a material comprising, under equilibrium solidification conditions at 1300K: a total mole fraction of transition metal borides and borocarbides ofbetween 5 and 50 %, wherein a metallic portion of the transition metal borides and borocarbides comprises greater than or equal to 15 wt. % W+Mo; and a mole fraction of isolated carbides in the material between 5 and 40%, wherein isolated carbides are defined as MC type carbides having one or more of the following elements: V, Ti, Nb, Zr, Hf, W, Mo, wherein the alloy comprises in wt. %: B: 1.6 - 2.3 C: 2 - 3 Cr: 0 - 0.01 Mo: 13-20 Mn: 0 - 3 Ni: 0 - 3 Si: 0 - 1.5 V: 8 - 14; wherein the balance consists of Fe and incidental impurities.

[0011] In some embodiments a mole faction of isolated carbides, where the metallic component of the carbide comprises greater than 50 wt. % vanadium, can be between 5 and 40 %.

[0012] The alloy comprises less than or equal to 0.01wt. % chromium. In some embodiments, the alloy can comprise no chromium.

[0013] In some embodiments, the material can comprise a total hard phase mole fraction at equilibrium at 1300K greater than or equal to 10%, wherein the hard phase is selected from the group consisting of borides, borocarbides, nitrides, carbides, oxides, silicides, laves phases, aluminides, and carbonitrides. In some embodiments, a mole fraction of embrittling hard phase in the material can comprise Fe2B, M 23 (C,B) 6 , M 7 (C,B) 3 , and M 3 (C,B) is less than or equal to 10% when measured at a matrix solidus temperature, wherein M is greater than or equal to 75wt. % Fe.

[0014] In some embodiments, a FCC-BCC transition temperature of the material under equilibrium solidification conditions can be less than or equal to 1300K. In some embodiments, a melt range of the material under equilibrium solidification conditions can be less than or equal to 250C, melt range being defined as the difference between a formation temperature of a first hard phase to solidify and a matrix liquidus temperature.

[0015] In some embodiments, the material can have a deposited hardness greater than or equal to 55HRC. In some embodiments, a hardness of the material after austenitizing and quenching can be greater than or equal to 55HRC. In some embodiments, a hardness of the material after austenitizing and quenching can be greater than or equal to 60HRC.

[0016] In some embodiments, the material can comprise an alloy with a specified ASTM G65 performance. In some embodiments, the material can comprise an alloy with a specified ASTM G65 performance after an austenitizing, quenching, and tempering process.

[0017] In some embodiments, the alloy can be a powder. In some embodiments, the alloy can be formed into a hardfacing layer.

[0018] Also disclosed herein are embodiments of a low chromium or chromium free ferrous alloy, wherein the alloy is formed into or configured to form a material comprising a total volume fraction of transition metal borides and borocarbides of between 5 and 50%, wherein a metallic component of the borides and borocarbides comprises greater than or equal to about 15wt% Ti+W+Mo+V.

[0019] The alloy comprises less than or equal to about 0.01wt% chromium. In some embodiments, the alloy can comprise no chromium.

[0020] In some embodiments, the total hard phase volume fraction of the material can be greater than or equal to 10%, where hard phases are borides, borocarbides, nitrides, carbides, oxides, silicides, laves phases, aluminides, and carbonitrides. In some embodiments, the volume fraction of embrittling hard phase of the material can be less than or equal to 10%, where embrittling hard phases comprise M 23 (C,B) 6 , M 7 (C,B) 3 , and M 3 (C,B) where M is greater than or equal to 75wt% Fe. In some embodiments, the material can have a volume fraction of isolated carbides of greater than or equal to 5%, where isolated carbides comprise MC type carbides comprising one or more of the following elements: V, Ti, Nb, Zr, Hf, W, Mo.

[0021] In some embodiments, the material can have an as deposited hardness greater than or equal to 60HRC. In some embodiments, the material can have an ASTM G65 procedure A mass loss of less than or equal to 0.16g.

[0022] In some embodiments, the disclosed alloy can be manufactured into a powder, wire, casting, and / or hardfacing layer for wear protection.

[0023] In some embodiments, the alloy can comprise, in weight percent, Fe and B: 1.64, C: 2, Mo: 13.6, V: 8.5, B: 1.8, C: 2.2, Mo: 15, V: 9.35, B: 2.2, C: 2.8, Mo: 17.7, V: 12, B: 2.05, C: 2.6, Mo: 16.3, V: 11.1, B: 1.64, C: 2, Mn: 1, Mo: 13.6, Ni: 1.3, Si: 0.5 V: 8.5, B: 1.8, C: 2.2, Mn: 1, Mo: 15, Ni: 1.5, Si: 0.5, V: 9.35, B: 2.2, C: 2.8, Mn: 1, Mo: 17.7, Ni: 1.7; Si: 0.5, V12, B: 2.05, C: 2.6, Mn: 1, Mo: 16.3, Ni: 1.6, Si: 0.5, V11.1, B: 2.0, C: 2.8, Mo: 18, V: 13, B: 2.0, C: 2.8, Mo: 18, V: 11.5, B: 1.85, C: 2.6, Mo: 18, V: 12, B: 2.0, C: 2.8, Mn: 0.5, Mo: 18, Ni: 1.5, Si: 0.5, V: 13, B: 2.0, C: 2.8, Mn: 0.5, Mo: 18, Ni: 1.5, Si: 0.5, V: 11.5, or B: 1.85, C: 2.6, Mn: 0.5, Mo: 18, Ni: 1.5, Si: 0.5, V: 12.

[0024] Also disclosed herein is mining equipment which can incorporate the alloy disclosed herein for wear protection. In some embodiments, the mining equipment can comprise ground engaging tools, work tools, lip shrouds, cutting edges, blades, wear plates, and comminution equipment.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 shows an example equilibrium solidification diagram of an embodiment of a disclosed alloy, not part of the invention, (X1). Figure 2 shows an example equilibrium solidification diagram of an embodiment of a disclosed alloy, not part of the invention, having the composition (B:2.2, C:2.2, Mo: 12, Ni:2, V:8). Figure 3 shows an example equilibrium solidification diagram of an alloy outside of the scope of the invention (B:3.8, C:0.8, Mn: 1.8, Nb:3, Ni: 1.9, Si:0.6, W:0.8). Figure 4 shows an example micrograph of an embodiment of a disclosed alloy, not part of the invention, (X1). Figure 5 shows an example micrograph of an embodiment of an alloy outside of the scope of the invention. DETAILED DESCRIPTION

[0026] This disclosure describes embodiments of ferrous alloys that can provide the same or better wear resistance compared to chromium bearing materials, with no or minimal amounts of chromium. Specifically, embodiments of the alloys described herein can form complex eutectic borides and / or borocarbides that contain a significant portion of tungsten and / or molybdenum in a hard ferrous matrix, which makes them suitable as hardbanding / hardfacing alloys, while having no or low levels of chromium. Additionally these alloys can form isolated carbides of the MC type which add to their wear resistance with little reduction in impact resistance or toughness.

[0027] Further, embodiments of alloys discussed herein specifically describe alloys that avoid the formation of intermetallics or iron borides for wear performance. Instead, alloys in embodiments of this disclosure derive their wear performance from borides and / or borocarbides of which the metallic component comprises a substantial portion of molybdenum. These iron borides are often undesirable for several reasons. Iron borides are typically substantially softer than borides of molybdenum and / or tungsten, reducing wear performance for a given phase fraction of boride. Additionally, they tend to form a needle like morphology, especially when present as a hypereutectic phase, reducing toughness and impact resistance. Titanium boride containing alloys often have poor weldability and significant oxide inclusions or porosity because titanium oxidizes very readily at the high temperatures seen during welding or other processing steps. Accordingly, the alloys of the invention do not rely on titanium for wear resistance.

[0028] As disclosed herein, the terms hardbanding / hardfacing alloys generally refer to a class of materials which are deposited onto a substrate for the purpose of producing a hard layer resistant to various wear mechanisms: abrasion, impact, erosion, gouging, etc. Embodiments of the disclosure can relate to hardfacing / hardfacing layers and components protected by hardfacing / hardfacing layers made of the alloys described herein. Alloys described in this disclosure relate generally to wear resistant materials. These alloys may be used as a surface coating or processed to create a bulk material via casting, sintering, hot pressing, forging, or any other manufacturing process used to manufacture metallic components.

[0029] As disclosed herein, the term alloy can refer to the chemical composition forming the powder disclosed within, the powder itself, and the composition of the metal component formed by the heating and / or deposition of the powder. Further, the alloy can be a wire, casting, or other bulk alloy.

[0030] In some embodiments, computational metallurgy can be used to explore alloy compositional ranges where the morphology, phase fraction, and composition of phases can be controlled to achieve a specific microstructure and performance. The Fe-B-C-W-Mo system is sufficiently complex that controlling the fraction, type, composition, and morphology of phases is not obvious even to one skilled in the art. With the addition of one or more of the following elements: V, Ti, Zr, Hf, Si, Mn, Ni, Nb this becomes even more challenging. With computational metallurgy, the thermodynamic characteristics and, as a result, the microstructure and physical properties of alloys containing these elements can be closely controlled.Metal Alloy Composition:

[0031] Embodiments of the disclosure can be defined by their particular metal alloy composition. As mentioned, embodiments of alloys disclosed herein can have no or limited chromium content. A limit is placed on the level of chromium in the alloy for at least these reasons: 1) Chromium free alloys may be applied as a deposit over chromium bearing materials resulting the incorporation of chromium in the alloy due to dilution. The chromium fumes released from such a process will still be less than those released from a higher chromium deposit, 2) Low levels of chromium may be incorporated into the alloy and still provide a significant reduction in chromium emissions compared to a standard alloy. This reduction may be enough to meet at least the following regulatory standards: OSHA- 1910.1026, 1915.1026, 1926.1026 and 3) Unintentional chromium impurities may be incorporated into an alloy via various pathways.

[0032] The low chromium or chromium free alloys comprise ≤0.01wt% chromium. In some embodiments, chromium free alloys can comprise 0wt% chromium.

[0033] In some embodiments, the alloy with low or no chromium can be described by specific compositions, in weight% with Fe making the balance. Alloys presented in Table 1 have been identified using computational metallurgy and experimentally manufactured successfully. In some embodiments, the alloys of Table 1 represent a final weld chemistry. These alloys meet the specific thermodynamic and microstructural embodiments described in this disclosure. Included are hardness and ASTM G65 procedure A wear testing results which are further discussed below. Table 1: Alloy Composition of Manufactured Ingots in wt.% with Fe BalanceB C Cr Mn Mo Ni Ti Si V HRC G65 Mass Loss X1* 1.31.611867MW(X1)-1* 1.381.613.49.0252X1-1* 1.491.7213.27.560.8X1-2* 1.641.916.19.9766.20.064X1-3* 1.331.5912.48.165X1-4* 1.502.0213.207.2859.4X1-5* 1.482.0013.206.4266.2X2* 1.471.6813.41.507.75680.068X3* 1.482.0013.2016.4268X2A 1.852.1515.251.510.5580.123X2B 1.92.415.251.510.5620.086X2C 2.12.5117.71.50.512630.050X2D 2.22.8117.71.50.51263.50.068X4* 1.602.000.5012.001.504.000.504.0065.2X5* 1.401.800.5012.001.501.000.507.0068.2X6* 1.402.200.5012.001.507.000.5062.4X7* 1.401.800.5012.001.507.000.5049X8 2.002.800.5018.001.504.000.5012.0069.2X9* 1.001.900.509.901.001.000.507.20X10* 1.101.800.509.901.007.000.507.20X11* 1.42.511410.510X12 1.62.511410.510X14* 1.71.111410.54X15* 0.42.81410.512X4.1* 0.851.50.70.3580.75.50.35X5.1* 0.851.70.70.3580.75.50.35X6.1* 0.551.5260.5762X7.1* 0.651.7260.5762.7X18.1* 0.651.720.76.4763X19.1* 0.651.70.50.76.8.4763X20 22.80.5181.50.511.5X21 22.80.5181.50.513X22 1.82.21151.5.59.35X23 1.852.6.5181.5.512*Not part of the present invention

[0034] In some embodiments, low or no chromium alloys can be described by a range in chemistry. This range may be used to describe both feedstock chemistries used to manufacture wire or powder or to describe a final alloy chemistry.

[0035] In some embodiments, manganese and / or silicon may be added to any of the described compositions to serve as a deoxidizing agent and to modify the properties of the melt. Generally, less than 5 wt. % manganese and / or silicon may be added.

[0036] The Fe content identified in all of the compositions described in the above paragraphs is the balance of the composition as indicated above, or alternatively, the balance is Fe and may include incidental impurities.

[0037] In some embodiments, alloys described in this disclosure may be manufactured into an atomized powder for cladding with PTA or laser, and for other powder metallurgy processing into a final part. These powders themselves may be fully described by their chemistry shown in Table 2. The alloys in Table 2, and welds made from the alloys, meet at least some of the thermodynamic, microstructure, performance, and other embodiments of this disclosure. The welding process can involve dilution with a substrate material to achieve a metallurgical bond. As a result, the chemistry of the weld may be changed from those listed above but can still satisfy some or all of the criteria discussed below. Table 2: Alloy Composition of Manufactured Powders in wt. % with Fe BalanceAlloy B C Mn Mo Ni Si V P1 22.80.5181.50.511.5P2 22.80.5181.50.513P3 1.82.21151.5.59.35P4 1.852.6.5181.5.512

[0038] In some embodiments, alloys manufactured into a solid or cored wire for welding or for use as a feedstock for another process may be described by specific chemistries. Table 3 describes cored wires that have been manufactured and can meet some or all of the specific criteria of this disclosure. As described above, when welded, there may be a degree of dilution with a substrate involved. When welded on steel and / or other iron based substrates, both the specified and diluted chemistries describe these alloys and meet the thermodynamic and microstructural embodiments described elsewhere in this disclosure. Dilution can typically range from 0% to 60%. Table 3: Alloy Composition of Manufactured Wires in wt.% with Fe BalanceAlloy B C Cr Mn Mo Ni Si V W1 1.852.150.0015.700.000.0011.00W2 1.852.15015.251.5010.5W3 1.92.4015.251.5010.5W4 2.12.5117.71.70.512W5 2.22.8117.71.70.512W6 1.82.6015.251.5010W7* 2.13.1117.71.70.512W8* 2.353.05119.31.70.513W9 1.62.7014.21.5010.3W10* 1.853.2116.51.70.512W11* 1.853.4116.51.70.512W12 1.82.2215019.35W13 1.82.611500.510.25W14 1.642213.6018.5W15 1.642.4113.600.59.3W16 1.82.21151.50.59.35W17 1.642113.61.50.58.5W18* 2.553.051.616.131.570.4710.95W19* 2.52.8117.71.70.512W20* 2.531.517.71.70.512W21 2.22.8117.71.70.512W22 22.61.616.31.570.4710.95W19.1* 1.12.850.951.2101.40.611.7W19.1A* 1.23.111.210.91.50.612.8W23* 1.341.460.7311.261.10.357.6W24* 1.491.70.9212.411.270.458.37W25* 1.521.740.8313.131.170.318.3W26* 1.522.020.9514.061.30.38.62W27* 1.31.630.7210.730.950.218.3W28* 1.161.220.738.250.820.36.67W29* 1.111.220.728.360.810..316.2W30* .952.45.818.61.2.510*Not part of the present invention.

[0039] In some embodiments, weld deposits of the disclosed alloys may also be described by specific compositions measured directly using a range of spectroscopy techniques. Table 4 lists alloy chemistries as-deposited on a substrate, measured using glow discharge spectroscopy (GDS), which can meet some or all of the thermodynamic, microstructural, and other embodiments of this disclosure. There is a degree of imprecision in any spectroscopy technique with accuracy depending on various factors, as such there is a margin of error involved in the reported values for each element. Table 4: Alloy Composition of Deposited Weld Chemistries in wt.% with Fe Balance*Alloy B C Mn Mo Ni Si V WELD-1 0.931.701.9612.400.310.687.14WELD-2 0.921.571.8011.800.290.666.53WELD-3 0.931.931.1212.300.360.517.46WELD-4 0.951.671.8011.000.320.706.36WELD-5 0.922.201.059.771.540.485.98WELD-6 1.072.841.1711.101.870.546.88WELD-7 0.621.410.890.180.330.696.25WELD-8 0.371.060.760.180.290.666.34WELD-9 0.901.871.8911.400.490.676.83WELD-10 0.731.771.9211.800.420.667.17WELD-11 0.791.900.9610.101.710.476.66WELD-12 0.932.021.1312.401.680.477.94WELD-13 0.781.541.109.701.300.496.43WELD-14 0.921.741.7811.000.520.696.34WELD-15 0.911.921.0112.901.610.477.70WELD-16 0.781.410.9610.201.340.416.38WELD-17 0.871.531.7811.200.270.576.20WELD-18 0.841.390.6811.501.490.506.90WELD-19 0.912.060.7410.201.550.526.56WELD-20 0.931.701.9612.400.310.687.14WELD-21 0.921.571.8011.800.290.666.53WELD-22 0.931.931.1212.300.360.517.46WELD-23 0.951.671.8011.000.320.706.36WELD-24 0.922.201.059.771.540.485.98WELD-25 1.072.841.1711.101.870.546.88WELD-26 0.911.761.2210.001.510.445.93WELD-27 0.962.271.0210.401.710.466.26WELD-28 0.952.471.1111.501.810.526.82WELD-29 1.012.481.2211.401.890.576.75WELD-30 1.032.331.099.761.650.555.78WELD-31 0.871.820.6711.401.610.496.87WELD-32 0.851.740.7310.501.540.516.17WELD-33 0.971.900.7311.201.580.536.86WELD-34 0.821.760.689.511.570.505.73WELD-35 0.862.301.0512.801.910.497.30WELD-36 0.952.371.2211.701.870.557.06WELD-37 0.912.331.1612.202.010.527.42WELD-38 0.962.201.2312.301.780.537.68WELD-39 0.882.040.7613.001.920.537.91*Not part of the present invention

[0040] In some embodiments, weld deposits of the disclosed alloys may also be described by specific compositions measured directly using a range of spectroscopy techniques. Table 5 lists alloy chemistries that fall under criteria described in this disclosure. These chemistries are measured using ICP, Leco C, and / or XRF spectroscopy techniques. There is a degree of imprecision in any spectroscopy technique with accuracy depending on various factors, as such there is a margin of error involved in the reported values for each element. Table 5: Alloy Composition in wt.% with Fe BalanceAlloy B C Cr Mn Mo Ni Si V W Alloy 1 1.922.61.9316.281.48.568.42Alloy 1 weld* 1.341.46.7311.261.1.357.6Alloy 2 1.952.75.8417.281.46.469.79Alloy 2 weld* 1.521.74.8313.131.17.318.3Alloy 3 weld* 1.621.91.2512.431.26.648.25Alloy 4 weld* 1.621.84.9411.51.16.478.37Alloy 5 1.962.72.5618.041.58.5213.06Alloy 6 1.82.19.9915.171.57.559.64Alloy 7 1.912.7.56181.6.712Alloy 8 1.92.76.5618.351.55.6312.91Alloy 9* 2.01.771.83.8317.762.561.4411.24.88*Not part of the present invention

[0041] In some embodiments, alloys described in this disclosure may be welded by a bulk process. These alloys are described in Table 6 by their nominal powder and final chemistries. In embodiments of this process, either a powder alloy is used or a powder is blended from other alloy powders (powder) such that its bulk chemistry reaches a target chemistry (final). The powder can be deposited on a substrate and steel wire can be welded on top of the powder and substrate. Thus, the final chemistry may be a combination of the powder, substrate, and / or steel wire along with any electrode used. This produces a weld deposit where the weld chemistry, microstructure, performance, and thermodynamics can be dictated by the parameters used and the chemistry of the powder. The primary welding parameters that change these properties are the powder to wire ratio and dilution of the weld puddle with the substrate. Powder to wire ratios using the powder described may range from 0.6:1 to 2.2:1. Dilution may range from 0% to 50%. Table 6: Alloy Compositions of Powder Used in Bulk Welding Process, and Final Chemistry of Weld Bead produced in Bulk Welding Process, all in wt.% with Fe BalanceAlloy B C Mn Mo Ni Si V B1* Powder4.325.272.1934.212.911.4023.60Final1.411.831.0011.301.000.507.80B2* Powder4.255.212.4033.963.011.5523.27Final1.411.831.0011.301.000.507.80*Not part of the present invention

[0042] Thus, the compositions disclosed in the above Tables 1-6 can be the compositions of the powder itself, the powder in combination with other materials (such as wires and substrates), the wire, the casting, or the final composition of the weld itself.Description of Alloying Additions

[0043] In this disclosure, certain specific alloying additions may be used to meet the various thermodynamic and microstructural criteria described below. The alloy additions described serve as examples.

[0044] Embodiments of the disclosure allow for the formation of specific types of borides. Boron is a necessary alloy addition to form borides in the alloy. Borides, especially the transition metal borides that form in a ferrous alloy system, can be harder than iron matrix phases. Having harder phases will improve wear performance, making embodiments of the disclosed alloys particularly suitable for hardfacing applications. These borides are different from the borides described in Wallin, discussed above, that comprise almost entirely iron and boron.

[0045] Molybdenum can be added to the alloy in sufficient quantity to form complex borides that have a different chemistry, structure, and properties than borides that comprise mostly iron and boron. The properties of these complex borides can include: 1) higher hardness allowing for the same wear performance with a lower boride phase fraction and higher toughness; 2) no rod like phases which is a less embrittling morphology further improving toughness; 3) a thermodynamically favorable phase allowing for precise control over the specific types of borides present in the alloy.

[0046] The above three alloying additions alone are sufficient to meet the microstructural and thermodynamic criteria of certain embodiments of this disclosure. However, additional alloying additions may be added for various reasons to modify the properties of the material and / or improve manufacture and processing.

[0047] Carbon is added for two primary reasons: 1) carbon promotes the formation of a martensitic matrix which is harder than the other matrix types including ferrite, austenite, pearlite, and bainite; 2) carbon can combine with transition metals to form carbides which improve wear performance.

[0048] The alloy of the invention comprises vanadium. Titanium, niobium, zirconium, hafnium, tantalum, and tungsten cannot be added to the alloy of the present invention in addition to carbon. These elements combine with carbon to form MC type carbides which form an isolated morphology and are extremely hard resulting in tough wear resistant alloys. In contrast, other carbides such as those formed by iron and / or chromium, do not form an isolated morphology and are considerably softer than the MC type described above. The MC type carbides also form at a sufficiently high temperature that control over the amount of carbon in the liquid during solidification is possible over a wide range of solidification conditions. This allows for the elimination of embrittling borocarbide phases and further control over the performance of the alloy.

[0049] In the present invention, vanadium is used as a carbide former instead of titanium, niobium, zirconium, hafnium, tantalum, and / or tungsten. This allows improved fluidity of the liquid alloy at high temperature as MC type carbides containing mostly vanadium tend to form at a lower temperature improving viscosity. This allows for easier atomization of the alloy into a powder, improved bead morphology during welding, and easier casting.

[0050] Nickel and manganese may be added to the alloy to modify the FCC-BCC transition temperature to allow for the austenitizing step in various heat treatments to happen at different temperatures. Nickel also slows the formation of pearlite, ferrite, and bainite during solidification, improving hardenability which allows for a martensitic matrix at lower cooling rate.

[0051] Silicon and / or manganese have deoxidizing effects on the alloy which improves performance and avoids porosity when utilized in various processes where oxygen is present.

[0052] Nickel, silicon, manganese, vanadium, molybdenum, boron and carbon all can improve the hardenability of the alloy by increasing the carbon equivalent of the matrix.Thermodynamic Criteria

[0053] Embodiments of alloys of the disclosure can be fully described by certain equilibrium thermodynamic criteria. The alloys can meet some, or all, of the described thermodynamic criteria.

[0054] A thermodynamic criterion is the total mole fraction of transition metal borides and borocarbides where the metallic component comprises ≥15wt% W+Mo. In some embodiments, a thermodynamic criterion is the total mole fraction of transition metal borides and borocarbides where the metallic component comprises ≥25wt% W+Mo. In some embodiments, a thermodynamic criterion is the total mole fraction of transition metal borides and borocarbides where the metallic component comprises ≥50wt% W+Mo.

[0055] This criteria will be abbreviated as "complex boride". Increasing the mole fraction of complex boride results in an improvement in the wear performance of the alloy. Because these complex boride phases are harder than borides with a metallic component that comprises mostly iron and / or chromium, a lower phase fraction is required to achieve comparable wear performance. For example, iron and / or chromium borides would have a hardness of 1700HV, whereas the borides described herein can have a hardness of greater than 2000HV. Toughness is inversely correlated with boride phase fraction in most alloys so providing the same wear performance with a lower fraction is advantageous.

[0056] The complex boride mole fraction is measured as the sum of all borides at equilibrium. In this disclosure the complex boride mole fraction and chemistry is measured at 1300K in an equilibrium solidification diagram. As the solubility of boron in a solid ferrous matrix is very small, 1300K is a very close approximation of the actual phase fraction in service. Phases that may meet the chemistry requirement may comprise M 2 B, M 3 B 2 , and B 2 M. In Figure 1 the complex boride phase fraction is 15.6% measured as the mole fraction of M3B2 at 1300K [101 ]. The metallic component of M 3 B 2 comprises ~74wt% Mo satisfying the chemistry limitation. The alloy in Figure 1 meets the most specific complex boride mole fraction embodiments but the alloy X1 of Figure 1 does not fall within the claimed composition and is therefore not part of the invention.

[0057] In contrast, the chrome free weld deposit described in Wallin does not meet the embodiments of this criteria. The solidification diagram of this alloy is shown in Figure 3. The boride and borocarbide phases all have < 15wt% W+Mo.

[0058] The complex boride mole fraction of the alloy is between 5% and 50%. In some embodiments, the complex boride mole fraction of the alloy can be between 10% and 35%. In some embodiments, the complex boride mole fraction of the alloy can be between 10% and 25. In some embodiments, the complex boride mole fraction of the alloy can be between 5% and 45%. In some embodiments, the complex boride mole fraction of the alloy can be between 5% and 30%. In some embodiments, the complex boride mole fraction of the alloy can be between 5% and 25%. In some embodiments, the complex boride mole fraction of the alloy can be between 7.5% and 30%. In some embodiments, the complex boride mole fraction of the alloy can be between 7.5% and 25%. In some embodiments, the complex boride mole fraction of the alloy can be between 10% and 30%. In some embodiments, the complex boride mole fraction of the alloy can be between 10% and 25. In some embodiments, the complex boride mole fraction of the alloy can be between 12.5% and 25%. In some embodiments, the complex boride mole fraction of the alloy can be between 12.5% and 20%.

[0059] A thermodynamic criterion is the mole fraction of isolated carbides. Examples of isolated carbides comprise MC type carbides that contain one or more of the following elements: V, Ti, Nb, Zr, Hf, W, Mo. Carbides formed from these elements can form in a discrete and isolated morphology which can reduce their impact on the alloy's toughness. M 7 C 3 , M 23 C 6 , and M 3 C, are examples of carbides that do not form an isolated morphology. Increasing the isolated carbide fraction allows for improved wear performance without embrittling the alloy.

[0060] The mole fraction of isolated carbides is the measured as the sum, at equilibrium, of all carbide phases that adhere to the above composition. This criteria is measured at 1300K. In the alloy of Figure 1 the only isolated carbide is VC, so the mole fraction of isolated carbide is 14.1% [102 ].

[0061] The isolated carbide mole fraction is ≥5% and <40%. In some embodiments, the isolated carbide mole fraction can be ≥10% and <40%. In some embodiments, the isolated carbide mole fraction can be ≥15% and <40%. In some embodiments, the isolated carbide mole fraction can be ≥10% and <30%. In some embodiments, the isolated carbide mole fraction can be ≥5% and <45%. In some embodiments, the isolated carbide mole fraction can be ≥5% and <30%). In some embodiments, the isolated carbide mole fraction can be ≥5% and <25%. In some embodiments, the isolated carbide mole fraction can be ≥5% and <20%. In some embodiments, the isolated carbide mole fraction can be ≥7.5% and <30%. In some embodiments, the isolated carbide mole fraction can be ≥7.5% and <25%. In some embodiments, the isolated carbide mole fraction can be ≥10% and <30%. In some embodiments, the isolated carbide mole fraction can be ≥10% and <25%. In some embodiments, the isolated carbide mole fraction can be ≥12.5% and <25%. In some embodiments, the isolated carbide mole fraction can be ≥12.5% and <20%.

[0062] In some embodiments the isolated carbides may comprise predominantly vanadium as the metallic component. These will be known as vanadium carbides defined as MC type carbides where M comprises ≥50% vanadium form at lower temperatures facilitating the manufacture of powder, castings, and other components. vanadium also is a cost effective alloying addition relative to its contribution to wear resistance.

[0063] In some embodiments, the vanadium carbide mole fraction is 0%. In some embodiments, the vanadium carbide mole fraction can be ≥5% and <40%. In some embodiments, the vanadium carbide mole fraction can be ≥10% and <40%. In some embodiments, the vanadium carbide mole fraction can be ≥15% and <40%. In some embodiments, the vanadium carbide mole fraction can be ≥10% and <30%. In some embodiments, the vanadium carbide mole fraction can be ≥5% and <45%. In some embodiments, the vanadium carbide mole fraction can be ≥5% and <30%. In some embodiments, the vanadium carbide mole fraction can be ≥5% and <25%. In some embodiments, the vanadium carbide mole fraction can be ≥5% and <20%. In some embodiments, the vanadium carbide mole fraction can be ≥7.5% and <30%. In some embodiments, the vanadium carbide mole fraction can be ≥7.5% and <25%. In some embodiments, the vanadium carbide mole fraction can be ≥10% and <30%). In some embodiments, the vanadium carbide mole fraction can be ≥10% and <25. In some embodiments, the vanadium carbide mole fraction can be ≥12.5% and <25%. In some embodiments, the vanadium carbide mole fraction can be ≥12.5% and <20%).

[0064] The next equilibrium thermodynamic criterion is the total hard phase mole fraction. Hard phases in this instance are borides, borocarbides, nitrides, carbides, oxides, silicides, laves phases, aluminides, and carbonitrides. In some instances, in this alloy space, it can be advantageous to have additional hard phases to complement the complex borides. This allows for fine tuning the microstructure, thermodynamics, and alloy properties. For example, carbides may be added to the microstructure to further increase the hard phase fraction and as a result the wear performance of the alloy without substantially changing the morphology of the complex borides. This can allow for an alloy with even more wear performance than provided by complex borides alone.

[0065] The total hard phase mole fraction is measured as the sum, at equilibrium, of all hard phases at 1300K. In Figure 1 this is calculated as the sum of the two hardphases present at 1300K, M 3 B 2 15.6% [101 ] and VC 14.1% [102 ]. The total hard phase mole fraction of the alloy in Figure 1 is 29.7% meeting some of the embodiments.

[0066] In some embodiments, the total hard phase mole fraction can be ≥5%. In some embodiments, the total hard phase mole fraction can be ≥10%. In some embodiments, the total hard phase mole fraction can be ≥15%. In some embodiments, the total hard phase mole fraction is ≥20%. In some embodiments, the total hard phase mole fraction can be ≥25%. In some embodiments, the total hard phase mole fraction can be ≥30%. In some embodiments, the total hard phase mole fraction can be ≥35%).

[0067] The next equilibrium thermodynamic criterion is the mole fraction of embrittling hard phase. In this disclosure, embrittling hard phase is the sum of Fe2B, M 23 (C,B) 6 , M 7 (C,B) 3 , and M 3 (C,B) that form before the solidus and where M is ≥75wt% Fe. These hard phases, when formed from the liquid during solidification, form an interconnected morphology that can embrittle the alloy reducing impact performance and toughness.

[0068] The mole fraction of embrittling hard phase is measured as the sum, at equilibrium, of Fe 2 B, M 23 (C,B) 6 , M 7 (C,B) 3 , and M 3 (C,B) at the solidus temperature. In Figure 1 there are none of these phases present at the solidus so the value is 0%. In Figure 2 this criteria is the mole fraction of M 3 (C,B) at the solidus, 16% [201 ]. Where the solidus is defined as one temperature step below the lowest temperature where a liquid phase is present [202 ]. In this alloy the liquidus temperature is 1300K [202 ].

[0069] In contrast, the Wallin alloy "Wallin #2" has a total embrittling hardphase fraction of 57% as shown in Figure 3. This is calculated as the sum of the mole fractions of Fe 2 B [301 ] and M 3 (C,B) [302 ] measured at 1300K. These values are measured at 35% and 22% respectively.

[0070] In some embodiments, the embrittling hard phase mole fraction can be ≤10%). In some embodiments, the embrittling hard phase mole fraction can be ≤5%). In some embodiments, the embrittling hard phase mole fraction can be ≤3%). In some embodiments, the embrittling hard phase mole fraction can be 0%.

[0071] The next equilibrium thermodynamic criterion is the FCC-BCC transition temperature. This transition temperature between austenite (FCC) and ferrite (BCC) indicates how the alloy will behave when subjected to various heat treatments. One example is when the alloy is applied as a coating on a steel substrate that will be subsequently hardened, such as quench and temper steel. The thermal cycle for hardening steels often involves transforming austenite into martensite and / or bainite. This can be done by heating the alloy in an austenitizing step to between 800C and 1000C then quenching in oil, water, or air. The success of this process can depend on a complete transformation of the matrix to austenite during heating. If the FCC-BCC transition temperature is near or above the austenitizing temperature of heat treatment cycle, complete transformation of the matrix to austenite will not occur and subsequent quenching will not form martensite or bainite

[0072] The FCC-BCC transition temperature is defined as one temperature step above the first formation temperature of the BCC phase (ferrite) under equilibrium solidification conditions. In Figure 1 the FCC-BCC transition temperature is 1200K [103 ]; in Figure 2 it is 1050K [203 ].

[0073] In some embodiments, the FCC-BCC transition temperature can be ≤1350K). In some embodiments, the FCC-BCC transition temperature can be ≤1300K. In some embodiments, the FCC-BCC transition temperature can be ≤1200K. In some embodiments, the FCC-BCC transition temperature can be ≤1150K. In some embodiments, the FCC-BCC transition temperature is ≤1100K. In some embodiments, the FCC-BCC transition temperature can be ≤1050K.

[0074] The next additional equilibrium thermodynamic criterion is the melt range of the alloy. The melt range of the alloy is the difference between the first hard phase formation temperature [104 ] and the liquidus temperature of the matrix [105 ] in Figure 1. If the carbides precipitate out from the liquid at elevated temperatures relative to the solidification of the matrix, this creates a variety of problems in the powder manufacturing process including powder clogging, increased viscosity, lower yields at desired powder sizes, and improper particle shape. Thus, it can be advantageous to reduce the formation temperature of the extremely hard particles.

[0075] The hard phase formation temperature of an alloy is defined as the highest temperature at which a hard phase is thermodynamically present in the alloy. This temperature is compared against the liquidus temperature of the iron matrix phase, whether austenite or ferrite, and used to calculate the melt range. It is desirable for the powder manufacturing process to minimize the melt range. In Figure 1 the hard phase (M 3 B 2 ) formation temperature is 1650K [104 ] and the liquidus temperature [105 ] is 1550K giving a melt range of 100K. This value is within the range of the most specific embodiment. The alloy in Figure 2 has a melt range of 250K [204 ] [205 ].

[0076] In some embodiments, the melt range can be ≤250K. In some embodiments, the melt range can be ≤200K). In some embodiments, the melt range can be ≤150K. In some embodiments, the melt range can be ≤100K.

[0077] In some embodiments boron may substitute for some of the carbon in the MC type carbides. In some embodiments carbon may substitute for some of the boron in the complex boride phases. In some embodiments, up to 10%, up to 20%, up to 30%, up to 40, or up to 50% carbon can substitute for the boron.

[0078] The following Table 7 describes 43 alloys claimed in this disclosure and their associated chemistry while Table 8 describes specific thermodynamic characteristics. Also included in the tables are 2 alloys, Wallin #1 and #2, as reference compositions not part of the invention. It can be seen that the Wallin alloys do not meet the specific thermodynamic criteria of this disclosure. Table 7 - Example CompositionsAlloyBCCrFeMnMoNbNiSiVW11.852.15069.3015.700011021.852.15068.75015.2501.5010.5031.92.4068.45015.2501.5010.5042.12.5062.5117.701.70.512051.82.6068.85015.2501.501006*2.13.1061.9117.701.70.51207*2.353.05059.1119.301.70.513081.62.7069.7014.201.5010.309*1.853.2063.25116.501.70.512010*1.853.4063.05116.501.70.5120111.82.2068.652150019.350121.82.6068.85115000.510.250131.642071.26213.60018.50141.642.4071.56113.6000.59.30151.642071.26113.601.50.58.5016*2.553.05063.681.616.1301.570.4710.95017*2.52.8061.8117.701.70.512018*2.53061.11.517.701.70.5120192.22.8062.1117.701.70.51202022.6064.511.616.301.570.4710.95021*1.12.850.9570.21.21001.40.611.7022*1.23.1167.71.210.901.50.612.8023*1.491.7073.390.9212.4101.270.458.37024*1.522.02071.230.9514.0601.30.38.62025*1.31.63076.160.7210.7300.950.218.3026*1.161.22080.850.738.2500.820.36.67027*1.111.22081.580.728.3600.8106.2028*0.952.450.874.518.601.20.51002922.8063.20.51801.50.511.503022.8061.70.51801.50.5130311.82.2068.6511501.50.59.350321.852.6063.050.51801.50.5120331.922.61067.80.9316.2801.480.568.42034*1.341.46076.160.7311.2601.10.357.60351.952.75065.470.8417.2801.460.469.79036*1.521.740730.8313.1301.170.318.3037*1.621.9072.651.2512.4301.260.648.25038*1.621.84074.10.9411.501.160.478.370391.962.72061.560.5618.0401.580.5213.060401.82.19068.090.9915.1701.570.559.640411.912.7062.530.561801.60.7120421.92.76061.340.5618.3501.550.6312.91043*21.771.8359.690.8317.7602.561.4411.240.88Wallin #14.21085.920.53.120.800.5Wallin #23.810.0187.091.80.431.90.600.4*Not part of the present invention

[0079] Table 8 shows the properties of the above-discussed alloys from Table 7. The column labeled "1" is the mole fraction of complex boride where the metallic constituent comprises Mo+W≥15wt%. The column labeled "2" is the mole fraction of complex boride where the metallic constituent comprises Mo+W≥25wt%. The column labeled "3" is the mole fraction of complex boride where the metallic constituent comprises Mo+W≥50wt%. The column labeled "4" is the weight percent of Mo+W in the metallic component of the complex boride. The column labeled "5" is the mole fraction of isolated carbide. The column labeled "6" is the mole fraction of vanadium carbide. The column labeled "7" is the total hard phase mole fraction. The column labeled "8" is the FCC-BCC transition temperature. The column labeled "9" is the melt range of the alloy. Table 8 - PropertiesAlloy12345678910.220.220.220.740.190.190.41120020020.220.220.220.730.190.190.41107520030.220.220.220.720.200.200.42105020040.240.240.240.740.220.220.4680025050.210.210.210.730.200.200.4010001506*0.240.240.240.730.230.230.477753007*0.260.260.260.730.250.250.5180030080.190.190.190.750.200.200.3910001509*0.210.210.210.750.240.240.4577530010*0.210.210.210.740.240.240.45750350110.200.200.200.750.180.180.391050200120.200.200.200.740.200.200.411050200130.180.180.180.750.160.160.361075200140.190.190.190.730.180.180.371050150150.190.190.190.730.160.160.35100015016*0.220.220.220.720.210.210.62100030017*0.260.260.260.700.220.220.51102535018*0.240.240.240.720.230.230.521000300190.240.240.240.730.230.230.481000250200.220.220.220.740.210.210.4477525021*0.130.130.130.740.230.230.3577515022*0.140.140.140.740.250.250.3977525023*0.180.180.180.730.150.150.33105015024*0.180.180.180.760.170.170.3580015025*0.160.160.160.730.150.150.3011005026*0.130.130.120.720.110.110.241150027*0.130.130.130.720.110.110.241100028*0.110.110.110.740.190.190.31800100290.230.230.230.750.220.220.45800250300.230.230.230.760.240.240.47800250310.210.210.210.740.180.180.391000200320.210.210.210.770.230.230.44825250330.220.220.220.730.170.170.3975025034*0.160.160.160.740.130.130.291100100350.220.220.220.750.200.200.4277520036*0.180.180.180.750.150.150.33102515037*0.180.180.180.730.160.160.35102515038*0.170.170.170.710.150.150.351100150390.230.230.230.770.240.240.47825250400.210.210.210.740.180.180.39800200410.220.220.220.770.230.230.45800250420.220.220.220.770.240.240.4682525043*0.240.240.240.760.170.170.411350300Wallin #10.000.000.000.040.030.000.711037.5500Wallin #20.000.000.000.040.030.000.671037.5475*Not part of the present invention

[0080] Table 9 below describes the bulk equilibrium thermodynamic chemistry of the boride phase in the alloys described above. Table 9: Bulk Equilibrium Thermodynamic Chemistry of Boride PhasesNoBCrFeMoNiw10.081700.23510.68330020.082300.24620.67040.0011030.082900.25880.65670.0016040.081800.23750.67970.0009050.082100.24270.67410.0011060.082100.24250.67410.0013070.082100.24320.67330.0013080.081500.23150.68620.0008090.081600.23240.68520.00090100.081700.23540.68180.0010110.081400.23020.688300120.082100.24280.675100130.081400.23070.687800140.082100.24390.67400150.082100.24330.67360.00090160.082900.25740.6580.00180170.083600.27110.64310.00230180.082900.25860.65660.00190190.082300.24650.66990.00130200.081700.23550.6820.00080210.08180.01180.22350.68250.00040220.08180.01210.22340.68220.00040230.082100.24270.67450.00070240.080800.21810.70080.00020250.082300.24680.67030.00060260.082700.25440.66230.00060270.082800.25780.65870.00060280.08180.01080.22470.68240.00030290.081200.22470.69360.00050300.08100.22050.69820.00040310.082100.24230.67470.00090320.080500.21220.70710.00010330.082200.24490.67180.00110340.081900.23920.67840.00050350.081500.23170.6860.00070360.081400.23020.68790.00040370.082300.24750.66940.00080380.083300.26610.64960.00110390.080700.21570.70330.00030400.081900.23990.67730.00090410.080700.21530.70370.00020420.080500.21240.70690.00010430.07980.01260.20460.67110.00030.032Wallin #10.086200.86570.01910.00980.019Wallin #20.08610.00030.86480.01980.00890.02

[0081] Table 10 and Table 11 show the chemistries and thermodynamic criteria for a list of alloys which meet the thermodynamic embodiments of this disclosure. Table 10 lists alloys where the isolated carbides may include but are not entirely composed of vanadium carbides. Titanium carbide and vanadium carbide are examples of potential isolated carbides. Table 11 lists alloys where all the isolated carbides are composed of vanadium carbide.

[0082] The column labeled "1" is the mole fraction of complex boride where the metallic constituent comprises Mo+W≥15wt%. The column labeled "2" is the mole fraction of complex boride where the metallic constituent comprises Mo+W≥25wt%. The column labeled "3" is the mole fraction of complex boride where the metallic constituent comprises Mo+W≥50wt%. The column labeled "4" is the weight percent of Mo+W in the metallic component of the complex boride. The column labeled "5" is the mole fraction of isolated carbide. The column labeled "6" is the mole fraction of vanadium carbide. The column labeled "7" is the total hard phase mole fraction. The column labeled "8" is the FCC-BCC transition temperature. The column labeled "9" is the melt range of the alloy. Table 10: Compositions and thermodynamic criteria for isolated carbides The examples comprising Nb and / or Ti are not part of the present invention.No B C Fe Mo Nb Ti V 1 2 3 4 5 6 7 8 9 M1961.82.270.5151.51821.2%21.2%21.2%73.4%18.4%16.8%39.6%1125450M2061.82.270.515118.521.2%21.2%21.2%73.5%18.6%18.2%39.7%1150400M2091.82.270152.508.521.3%21.3%21.3%73.4%18.7%16.8%40.0%1125450M2251.82.270151.518.521.2%21.2%21.2%73.5%18.9%17.4%40.1%1150450M2341.82.269.5152.51821.3%21.3%21.3%73.6%19.1%15.6%40.3%1150450M2351.82.270151.509.521.2%21.2%21.2%73.5%19.1%18.7%40.3%1150400M2361.82.2701511.58.521.1%21.1%21.1%73.6%19.1%18.9%40.2%1175400M2371.82.269.5152.50.58.521.3%21.3%21.3%73.5%19.1%16.3%40.4%1150450M2511.82.269153.508.521.4%21.4%21.4%73.5%19.3%16.0%40.7%1150450M2541.82.269.5151.52821.2%21.2%21.2%73.7%19.3%17.6%40.5%1200450M2581.82.269.5151.51921.2%21.2%21.2%73.6%19.4%17.9%40.6%1200450M2661.82.269.51511.5921.1%21.1%21.1%73.7%19.5%19.3%40.6%1200400M2711.82.269.5151.501021.2%21.2%21.2%73.5%19.5%19.2%40.7%1175400M2721.82.269152.50.5921.3%21.3%21.3%73.6%19.6%16.8%40.8%1200450M2731.82.2691522821.2%21.2%21.2%73.7%19.6%16.2%40.8%1250450M2751.82.269.51510.51021.1%21.1%21.1%73.6%19.6%19.4%40.7%1200350M2761.82.2691521.58.521.2%21.2%21.2%73.7%19.6%16.6%40.8%1250450M2801.82.269151.528.521.1%21.1%21.0%74.0%19.6%17.9%40.7%1250450M2811.82.269152.509.521.3%21.3%21.3%73.6%19.6%17.9%40.9%1175450M2871.82.2691520.59.521.2%21.2%21.2%73.6%19.7%17.8%40.9%1200450M2931.82.268.5153.50921.4%21.4%21.4%73.6%19.7%16.6%41.1%1200450M2941.82.268154.50.5821.5%21.5%21.5%73.7%19.8%14.0%41.2%1200450M3071.82.268.51521.5921.2%21.2%21.0%74.1%19.9%16.9%41.0%1275450M3121.82.268.515309.521.3%21.3%21.3%73.6%19.9%17.4%41.2%1200450M3131.82.2681532821.2%21.2%21.1%74.1%19.9%14.0%41.1%1325450M3151.82.268.5151.52921.1%21.1%20.9%74.1%19.9%18.2%41.0%1350450M3171.82.267.5155.50821.6%21.6%21.6%73.7%19.9%6.1%41.5%1200450M3231.82.267.51550.5821.5%21.5%21.5%73.8%20.0%13.6%41.5%1250450M3241.82.2681540921.4%21.4%21.4%73.7%20.0%3.9%41.4%1200450M3271.82.268152.52.5821.2%21.2%21.0%74.1%20.0%14.8%41.2%1625400M3301.82.268153.50.5921.3%21.3%21.3%73.8%20.0%15.8%41.3%1250450M3321.82.2681522.58.521.1%21.1%20.8%74.3%20.0%16.5%41.1%1650400M3341.82.268.51520.51021.2%21.2%21.1%73.9%20.0%18.1%41.2%1250450M3361.82.268.5152.501021.3%21.3%21.3%73.7%20.0%18.3%41.3%1225450M3421.82.263.51554.5821.0%21.0%19.5%76.4%20.0%19.3%41.0%0400M3451.82.267.515508.521.5%21.5%21.5%73.7%20.0%5.3%41.5%1250450M3471.82.267152.538.521.0%21.0%20.3%75.2%20.0%14.2%41.1%0400M3491.82.267.5154.50.58.521.4%21.4%21.3%74.0%20.1%14.4%41.5%1250450M3631.82.266.5153.53821.1%21.1%20.3%75.3%20.1%11.0%41.2%0400M3661.82.2681522921.1%21.1%20.9%74.1%20.1%16.9%41.2%1650450M3691.82.264.515349.520.8%20.8%19.4%76.3%20.1%11.0%40.9%0400M3701.82.263.5155.54821.1%21.1%19.6%76.4%20.1%17.0%41.2%0400M3721.82.266.5152.53921.0%21.0%20.0%75.5%20.1%14.2%41.1%0400M3731.82.264.5152.541020.8%20.8%19.3%76.4%20.1%7.9%40.9%0400M3741.82.267155.50.5821.5%21.5%21.3%74.2%20.1%13.0%41.6%1275450M3751.82.2671532.58.521.1%21.1%20.5%74.9%20.1%13.5%41.2%1700400M3771.82.262.51544.51020.8%20.8%19.1%76.7%20.1%17.3%40.9%0500M3811.82.263155.548.521.0%21.0%19.5%76.5%20.1%16.9%41.2%0400M3871.82.2661533921.0%21.0%20.0%75.7%20.1%12.5%41.1%0400M3921.82.265.5154.53821.1%21.1%20.1%75.7%20.2%11.4%41.3%0400M3951.82.267151.52.51020.9%20.9%20.1%75.3%20.2%18.6%41.1%0400M3961.82.264.5154.53.58.521.0%21.0%19.7%76.2%20.2%13.0%41.2%0400M3971.82.263154.549.520.9%20.9%19.3%76.6%20.2%15.0%41.1%0400M4021.82.264.51543.5921.0%21.0%19.6%76.2%20.2%11.8%41.1%0400M4041.82.262.515549.520.9%20.9%19.3%76.6%20.2%15.9%41.1%0400M4061.82.267.5153.51921.3%21.3%21.1%74.1%20.2%5.1%41.5%1325450M4091.82.267153.528.521.2%21.2%20.7%74.6%20.2%13.3%41.4%1675450M4121.82.2651553821.2%21.2%20.1%75.8%20.2%12.3%41.4%0400M4181.82.267154.51.5821.4%21.4%21.2%74.1%20.2%12.5%41.6%1625450M4191.82.2671532921.1%21.1%20.6%74.8%20.2%14.4%41.4%1675450M4201.82.2651543921.0%21.0%19.8%76.0%20.2%10.2%41.2%0400M4231.82.267152.529.521.1%21.1%20.4%75.0%20.2%15.7%41.3%0450M4271.82.263.5154.53.59.521.0%21.0%19.5%76.4%20.2%12.9%41.2%0400M4281.82.263155.53.5921.0%21.0%19.5%76.5%20.2%14.8%41.3%0400M4341.82.265.5154.52.58.521.1%21.1%20.2%75.6%20.3%10.3%41.4%0400M4351.82.266.5156.50821.6%21.6%21.4%74.2%20.3%7.4%41.9%1275450M4361.82.2671541.58.521.3%21.3%21.0%74.3%20.3%13.4%41.6%1650450M4381.82.264155.538.521.1%21.1%19.8%76.2%20.3%13.2%41.4%0400M4421.82.256.5151509.521.8%21.8%19.8%76.8%20.3%18.7%43.3%0400M4461.82.262.51553.51021.0%21.0%19.3%76.6%20.3%13.8%41.2%0400M4531.82.265.5155.52821.3%21.3%20.5%75.3%20.3%9.8%41.6%0400M4551.82.26415431020.9%20.9%19.5%76.3%20.3%10.2%41.3%0400M4601.82.2651542.59.521.0%21.0%19.9%75.9%20.3%11.4%41.4%0400M4621.82.267152.51.51021.1%21.1%20.5%74.9%20.4%16.4%41.4%1675450M4661.82.266.51541.5921.2%21.2%20.7%74.8%20.4%13.5%41.6%1675450M4671.82.2651562821.3%21.3%20.4%75.5%20.4%11.3%41.7%0400M4681.82.263.51572.5821.3%21.3%20.0%76.1%20.4%14.1 %41.6%0400M4741.82.267.5152.511021.2%21.2%20.9%74.2%20.4%3.3%41.6%1650450M4771.82.266.5153.51.59.521.2%21.2%20.5%75.0%20.4%14.5%41.5%1700450M4781.82.263157.52.5821.3%21.3%20.0%76.2%20.4%14.8%41.7%0400M4811.82.264.5156.52821.3%21.3%20.3%75.7%20.4%12.0%41.7%0400M4831.82.265.51561.5821.4%21.4%20.7%75.0%20.4%10.1%41.8%0400M4851.82.2651552921.2%21.2%20.2%75.7%20.4%10.8%41.6%0400M4861.82.262.51582.5821.3%21.3%19.9%76.3%20.4%15.6%41.7%0400M4871.82.266.515518.521.4%21.4%21.1%74.3%20.4%7.4%41.8%1650450M4911.82.257.51511.521021.4%21.4%19.4%76.9%20.4%18.7%42.2%0400M4921.82.262.5157.52.58.521.3%21.3%19.8%76.4%20.4%14.8%41.7%0400M4931.82.265154.529.521.1%21.1%20.0%75.8%20.4%11.7%41.5%0400M4941.82.2661561821.5%21.5%21.1%74.4%20.4%8.9%41.9%1650450M4961.82.264.5155.52921.2%21.2%20.1%75.8%20.4%10.1%41.6%0400M4971.82.2661541.59.521.2%21.2%20.4%75.2%20.4%13.7%41.6%0450M4991.82.265156.51.5821.4%21.4%20.6%75.3%20.5%10.8%41.8%0400M5001.82.263.51552.51021.0%21.0%19.6%76.3%20.5%10.7%41.5%0400M5041.82.266153.51.51021.1%21.1%20.3%75.3%20.5%14.6%41.6%0450M5051.82.2621582.58.521.3%21.3%19.8%76.4%20.5%15.5%41.8%0400M5091.82.266.515419.521.2%21.2%20.7%74.7%20.5%5.8%41.7%1675450M5111.82.266155.518.521.4%21.4%20.9%74.6%20.5%8.2%41.9%1675450M5121.82.2641562921.2%21.2%20.0%76.0%20.5%11.2%41.7%0400M5201.82.262.51562.51021.1%21.1%19.6%76.5%20.5%12.4%41.6%0400M5211.82.266.5153.511021.2%21.2%20.6%74.9%20.5%15.5%41.7%1675450M5231.82.263157.528.521.3%21.3%20.0%76.2%20.5%13.4%41.8%0400M5281.82.2581511.52.5921.4%21.4%19.5%76.9%20.5%20.2%42.0%0400M5291.82.264157.51.5821.4%21.4%20.4%75.7%20.5%12.2%41.9%0400M5321.82.261.51572.51021.1%21.1%19.5%76.6%20.5%13.9%41.7%0400M5331.82.2651571821.5%21.5%20.8%75.1%20.5%10.3%42.0%0400M5341.82.257.51511.52.59.521.4%21.4%19.4%77.0%20.5%20.1%42.0%0400M5351.82.2631572921.3%21.3%19.9%76.2%20.5%12.6%41.8%0400M5361.82.262158.528.521.4%21.4%19.9%76.4%20.6%14.8%41.9%0400M5381.82.264.51561.5921.3%21.3%20.2%75.7%20.6%10.0%41.8%0400M5411.82.2661560.58.521.5%21.5%21.2%74.3%20.6%7.8%42.1%1650450M5441.82.261.515928.521.4%21.4%19.9%76.4%20.6%15.5%41.9%0400M5461.82.263156.529.521.2%21.2%19.8%76.3%20.6%11.9%41.8%0400M5471.82.266.5154.50.59.521.3%21.3%21.0%74.4%20.6%5.6%41.9%1650450M5481.82.263.5157.51.58.521.4%21.4%20.2%75.9%20.6%12.2%41.9%0400M5491.82.2621582921.3%21.3%19.8%76.4%20.6%14.1 %41.9%0400M5501.82.26015112821.5%21.5%19.9%76.6%20.6%2.3%42.1%0400M5511.82.258.515102.51021.3%21.3%19.3%76.9%20.6%2.6%41.9%0400M5541.82.260.5151028.521.4%21.4%19.8%76.6%20.6%3.7%42.0%0400M5551.82.2651561921.3%21.3%20.5%75.3%20.6%8.8%41.9%0450M5591.82.265.5154.511021.2%21.2%20.4%75.3%20.6%6.5%41.8%0450M5601.82.2641561.59.521.2%21.2%20.1%75.9%20.6%9.9%41.8%0400M5611.82.2591511.528.521.5%21.5%19.7%76.8%20.6%18.9%42.1%0400M5651.82.261.515829.521.3%21.3%19.7%76.5%20.6%14.0%41.9%0400M5661.82.265157.50.5821.6%21.6%21.0%74.8%20.6%9.9%42.2%1675450M5671.82.26015102921.4%21.4%19.7%76.7%20.6%3.8%42.0%0400M5721.82.258.51511.52921.5%21.5%19.6%76.8%20.6%18.8%42.1%0400M5741.82.261.5157.521021.2%21.2%19.6%76.5%20.7%13.2%41.9%0400M5771.82.265.51560.5921.4%21.4%20.8%74.8%20.7%7.7%42.1%1675450M5811.82.262.51581.5921.4%21.4%20.0%76.2%20.7%12.8%42.0%0400M5821.82.2631571.59.521.3%21.3%20.0%76.2%20.7%11.3%41.9%0400M5831.82.257.5151229.521.5%21.5%19.5%76.9%20.7%1.2%42.2%0400M5901.82.262158.51.5921.4%21.4%20.0%76.3%20.7%13.5%42.1%0400M5911.82.263156.51.51021.2%21.2%19.9%76.2%20.7%10.6%41.9%0400M5941.82.2591512.51.5821.7%21.7%19.9%76.7%20.7%1.6%42.4%0400M5951.82.258151121021.4%21.4%19.4%76.9%20.7%2.7%42.1%0400M5961.82.264.5157.50.58.521.5%21.5%20.7%75.2%20.7%9.8%42.2%0450M5981.82.266.5154.501021.4%21.4%21.1%74.2%20.7%16.3%42.1%1650450M6001.82.264156.519.521.3%21.3%20.2%75.8%20.7%9.5%42.0%0450M6041.82.260.515101.5921.5%21.5%19.8%76.6%20.7%15.5%42.2%0400M6061.82.262.515918.521.5%21.5%20.2%76.1%20.7%13.0%42.2%0400M6071.82.25715141921.7%21.7%19.7%76.9%20.7%19.7%42.7%0400M6091.82.2611591.59.521.4%21.4%19.8%76.5%20.8%14.1 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[0083] In some embodiments, the chromium free alloys can be described fully described by microstructural criterion. The alloys can meet some, or all, of the described microstructural criteria.

[0084] The main microstructural criterion is the total volume fraction of transition metal borides and borocarbides where the metallic component comprises ≥15wt% W+Mo. In some embodiments, a thermodynamic criterion is the total volume fraction of transition metal borides and borocarbides where the metallic component comprises ≥25wt% W+Mo. In some embodiments, a thermodynamic criterion is the total volume fraction of transition metal borides and borocarbides where the metallic component comprises ≥50wt% W+Mo.

[0085] This criteria will be abbreviated as "complex boride and borocarbide". Increasing the volume fraction of complex boride can result in an improvement in the wear performance of the alloy. Because these complex boride phases are harder than borides with a metallic component that comprises mostly iron and / or chromium, a lower phase fraction is required to achieve comparable wear performance. Toughness is inversely correlated with boride phase fraction in most alloys so providing the same wear performance with a lower fraction is advantageous.

[0086] The complex boride volume fraction is measured as the sum of all borides and borocarbides, which meet the chemistry requirement described above. In this disclosure the complex boride volume fraction is measured using quantitative metallography. Phases that may meet the chemistry requirement may comprise M 2 B, M 3 B 2 , and B 2 M. In Figure 4 the complex boride phase fraction is 20% measured as the volume fraction of the light colored M 3 B 2 phase [401 ]. The metallic component of the complex boride phase comprises ~25wt% Mo satisfying the chemistry limitation. The alloy in Figure 1 meets the most specific complex boride volume fraction embodiments.

[0087] In contrast, the chrome free weld deposit, described in Wallin does not meet the embodiments of this criteria. A micrograph of this alloy is shown in Figure 5. All the boride and borocarbide phases including iron boride [501 ] and niobium borocarbide

[502] have <15wt% W+Mo. This deposit, because it has numerous large borocarbide and / or boride phases present in the microstructure, has lower impact resistance and toughness. This can result in lower impact performance and subsequently lower life in service.

[0088] In some embodiments, the complex boride volume fraction of the alloy is between 5 and 50%. In some embodiments, the complex boride volume fraction of the alloy can be between 5 and 35%. In some embodiments, the complex boride volume fraction of the alloy can be between 10 and 40%. In some embodiments, the complex boride volume fraction of the alloy can be between 15% and 45%. In some embodiments, the complex boride volume fraction of the alloy can be between 10% and 35%. In some embodiments, the complex boride volume fraction of the alloy can be between 5% and 45%. In some embodiments, the complex boride volume fraction of the alloy can be between 5% and 30%. In some embodiments, the complex boride volume fraction of the alloy can be between 5% and 25%. In some embodiments, the complex boride volume fraction of the alloy can be between 7.5% and 30%. In some embodiments, the complex boride volume fraction of the alloy can be between 7.5% and 25% (. In some embodiments, the complex boride volume fraction of the alloy can be between 10% and 30%. In some embodiments, the complex boride volume fraction of the alloy can be between 10% and 25%. In some embodiments, the complex boride volume fraction of the alloy can be between 12.5% and 25%. In some embodiments, the complex boride volume fraction of the alloy can be between 12.5% and 20%.

[0089] The next microstructural criterion is the volume fraction of isolated carbides. Examples of isolated carbides include those of the MC type that comprise mostly of one or more of the following elements: V, Ti, Nb, Zr, Hf, W, Mo. The alloys of the invention comprise only V and Mo in the claimed ranges. Carbides formed from these elements can form in a discrete and isolated morphology which reduces their impact on the alloy's toughness. This allows for increasing hard phase fraction and wear performance without embrittling the alloy. In contrast, M 23 C 6 , M 7 C 3 , and M 3 C are all examples of carbides that do not form an isolated morphology.

[0090] The volume fraction of isolated carbides is the measured as the sum, in cross section, of all carbide phases that adhere to the above composition. In the alloy of Figure 4, the only isolated carbide is (Mo,V)C, so the volume fraction of isolated carbide is 13% [402 ].

[0091] In some embodiments, the isolated carbide volume fraction can be 0%. In some embodiments, the isolated carbide volume fraction can be ≥5% and <40%. In some embodiments, the isolated carbide volume fraction can be ≥10% and <40%. In some embodiments, the isolated carbide volume fraction can be ≥15% and <40%. In some embodiments, the isolated carbide volume fraction can be ≥10% and <30. In some embodiments, the isolated carbide volume fraction can be ≥5% and <45%. In some embodiments, the isolated carbide volume fraction can be ≥5% and <30%. In some embodiments, the isolated carbide volume fraction can be ≥5% and <25%. In some embodiments, the isolated carbide volume fraction can be ≥5% and <20% In some embodiments, the isolated carbide volume fraction can be ≥7.5% and <30%. In some embodiments, the isolated carbide volume fraction can be ≥7.5% and <25%. In some embodiments, the isolated carbide volume fraction can be ≥10% and <30%. In some embodiments, the isolated carbide volume fraction can be ≥10% and <25%. In some embodiments, the isolated carbide volume fraction can be ≥12.5% and <25%. In some embodiments, the isolated carbide volume fraction can be ≥12.5% and <20%.

[0092] In some embodiments the isolated carbides may comprise predominantly vanadium as the metallic component. These will be known as vanadium carbides defined as MC type carbides where M comprises ≥50% vanadium formed at lower temperatures facilitating the manufacture of powder, castings, and other components. Vanadium also is a cost effective alloying addition relative to its contribution to wear resistance.

[0093] The volume fraction of vanadium carbides is the measured as the sum of all MC type carbides that meet the above chemistry limitation. This criteria is measured at using a range of techniques including x-ray diffraction and quantitative microscopy to determine the volume fraction.

[0094] In some embodiments, the vanadium carbide volume fraction can be 0%. In some embodiments, the vanadium carbide volume fraction can be ≥5% and <40%. In some embodiments, the vanadium carbide volume fraction can be ≥10% and <40%. In some embodiments, the vanadium carbide volume fraction can be ≥15% and <40%. In some embodiments, the vanadium carbide volume fraction can be ≥10% and <30%. In some embodiments, the vanadium carbide volume fraction can be ≥5% and <45%. In some embodiments, the vanadium carbide volume fraction can be ≥5% and <30%. In some embodiments, the vanadium carbide volume fraction can be ≥5% and <25%. In some embodiments, the vanadium carbide volume fraction can be ≥5% and <20. In some embodiments, the vanadium carbide volume fraction can be ≥7.5% and <30%. In some embodiments, the vanadium carbide volume fraction can be ≥7.5% and <25%. In some embodiments, the vanadium carbide volume fraction can be ≥10% and <30%. In some embodiments, the vanadium carbide volume fraction can be ≥10% and <25%. In some embodiments, the vanadium carbide volume fraction can be ≥12.5% and <25%. In some embodiments, the vanadium carbide volume fraction can be ≥12.5% and <20%).

[0095] Microstructural criteria can correlate very closely with thermodynamic criteria. For example, the alloy B: 1.4, C: 1.9, Mo: 14, V: 10, Fe: balance, has a calculated complex boride mole fraction of 17% and a vanadium carbide mole fraction of 18%. Using quantitative scanning electron microscopy, the volume fraction of complex boride was measured at 20% and vanadium carbide at 14%.

[0096] The next microstructural criterion is the total hard phase volume fraction. Hard phases in this instance are borides, borocarbides, nitrides, carbides, oxides, silicides, laves phases, aluminides, and carbonitrides. In some instances, in this alloy space, it can be advantageous to have additional hard phases to complement the complex borides. This allows for fine tuning the microstructure and alloy properties. For example, carbides may be added to the microstructure to further increase the hard phase fraction and as a result the wear performance of the alloy without substantially changing the morphology of the complex borides or other phases. This can allow for an alloy with even more wear performance than provided by complex borides or borocarbides alone.

[0097] The total hard phase volume fraction is measured as the sum of all hard phases, where a hard phase is any phase with a hardness ≥1000HV. In Figure 4 this is calculated as the sum of the lightest phase 20% [401 ] and the darkest phase (Mo,V)C 13%

[0098] [402 ]. The total hard phase volume fraction of the alloy in Figure 4 is 33% meeting some of the embodiments.

[0099] In some embodiments, the total hard phase volume fraction can be ≥5%. In some embodiments, the total hard phase volume fraction can be ≥10%. In some embodiments, the total hard phase volume fraction can be ≥15%. In some embodiments, the total hard phase volume fraction can be ≥20%. In some embodiments, the total hard phase volume fraction can be ≥25%. In some embodiments, the total hard phase volume fraction can be ≥30%. In some embodiments, the total hard phase volume fraction can be ≥35%.

[0100] The next microstructural criterion is the volume fraction of embrittling hard phase. In this disclosure, embrittling hard phase is the sum of M 23 (C,B) 6 , M 7 (C,B) 3 , and M 3 (C,B) that form before the solidus and where M is ≥75wt% Fe. These phases are identified by EBSD, XRD, and / or EDX. These hard phases form an interconnected morphology that can embrittle the alloy reducing impact performance and toughness.

[0101] The volume fraction of embrittling hard phase is measured as the sum of Fe2B, M 23 (C,B) 6 , M 7 (C,B) 3 , and M 3 (C,B) in cross section. In Figure 4 there are none of these phases present at the solidus so the value is 0%.

[0102] In some embodiments, the embrittling hard phase volume fraction can be ≤10%. In some embodiments, the embrittling hard phase volume fraction can be ≤5%. In some embodiments, the embrittling hard phase volume fraction can be ≤3%. In some embodiments, the embrittling hard phase volume fraction can be 0%.Powder Manufacture

[0103] It is often advantageous to manufacture an alloy into a powder as an intermediary step in producing a bulk product or applying a coating to a substrate. Powder can be manufactured via atomization or other manufacturing methods. The feasibility of such a process for a particular alloy is often a function of the alloy's solidification behavior and thus its thermodynamic characteristics.

[0104] To make a production of powder for processes such as PTA, HVOF, laser welding, and other powder metallurgy processes, it can be advantageous to be able to manufacture the powder at high yields in the size range specified above. The manufacturing process can include forming a melt of the alloy, forcing the melt through a nozzle to form a stream of material, and spraying water or air at the produced stream of the melt to solidify it into a powder form. The powder is then sifted to eliminate any particles that do not meet the specific size requirements.

[0105] Embodiments of the disclosed alloys can be produced as powders in high yields to be used in such processes. On the other hand, many alloys, such as those described in Wallin and other common wear resistant materials, would have low yields due to their properties, such as their thermodynamic properties, when atomized into a powder. Thus, they would not be suitable for powder manufacture.

[0106] The manufacturability is commonly characterized by the yield of intended powder size produced during the manufacturing process. In some embodiments, the alloy can be manufactured into a 53-180 µm powder size distribution at a 50% or greater yield. In some embodiments, the alloy can be manufactured into a 53-180 µm powder size distribution at a 60% or greater yield. In some embodiments, the alloy can be manufactured into a 53-180 µm powder size distribution at a 70% or greater yield.Wire Manufacture

[0107] It is often beneficial to manufacture an alloy into a wire as a feedstock for protecting a hardfacing coating via GMAW, GTAW, hot wire GTAW, OAW, SAW, laser cladding, and other application methods. Hardfacing wire is typically produced using a cored wire process where a metal strip is rolled around a core or fill of alloy powder. The resulting chemistry of the wire can match the specific embodiments elsewhere in this disclosure.

[0108] The price and feasibility of such a manufacturing process is a function of the achievable powder fill to metal strip ratio. This ratio varies based on the wire size and other factors. Additionally, different wires may be used for different application processes. Typically these processes will all produce a variable range of dilution when applied.

[0109] Alloys in this disclosure may be formulated into a wire such that a 5 to 50% dilution range will produce an alloy that meets the specific thermodynamic and microstructural embodiments. In some embodiments, a 5 to 15% dilution range will produce an alloy that meets the specific thermodynamic and microstructural embodiments. In some embodiments, a 10 to 25% dilution range will produce an alloy that meets the specific thermodynamic and microstructural embodiments. In some embodiments, a 15 to 35% dilution range will produce an alloy that meets the specific thermodynamic and microstructural embodiments. In some embodiments, a 20 to 40% dilution range will produce an alloy that meets the specific thermodynamic and microstructural embodiments. In some embodiments, a 25 to 35 dilution range will produce an alloy that meets the specific thermodynamic and microstructural embodiments.

[0110] Alloys in this disclosure may also be formulated to achieve the maximum possible fill possible for a given wire size. The wires may also be formulated to use ferro alloy powder additions to the core to reduce price. These ferro alloy additions may comprise all or a portion of the core fill.Performance

[0111] Wear resistant alloys are often described by their performance in laboratory testing. The disclosed tests correlate well with wear resistant components in service.

[0112] In some embodiments, the alloy hardness can be ≥55HRC. In some embodiments the alloy hardness can be ≥58HRC. In some embodiments, the alloy hardness is ≥60HRC. In some embodiments the alloy hardness can be ≥62HRC. In some embodiments, the alloy hardness can be ≥64HRC.

[0113] In some embodiments the alloy has an ASTM G65 procedure A mass loss ≤0.2g. In some embodiments the alloy has an ASTM G65 procedure A mass loss ≤0.16g. In some embodiments the alloy has an ASTM G65 procedure A mass loss ≤0.12g. In some embodiments the alloy has an ASTM G65 procedure A mass loss ≤0.1g. In some embodiments the alloy has an ASTM G65 procedure A mass loss ≤0.08g.Heat Treatment and Performance

[0114] Across many applications, especially those in mining and other industries, it can be advantageous to hardface a quench and temper type of steel to provide additional wear protection. The process of hardfacing yields a heat affected zone in the quench and temper substrate that may reduce the substrate yield strength and toughness. This reduction in toughness can lead to component failure due to impact or excessive stress during operation.

[0115] To combat this failure mechanism, alloys in this disclosure may be formulated to have similar performance both as welded and after a quench and temper cycle. These alloys maintain similar hardness and high wear resistance when subjected to the industry standard ASTM G65 testing.

[0116] Table 12 describes the results of wear testing a hardfacing deposit produced with a nominal bulk wire chemistry according to the invention of B:2.2, C:2.8, Mn:1, Mo:17.7, Ni:1.7 Si:0.5, and V:12. Samples of this hardfacing layer were subjected to a range of austenitizing temperatures for 2 hours then quenched in water. Then the samples were tempered at 150C for 5 hours. Reference is made to the standard ASTM G65 range for hardfacing produced using this feedstock wire. This demonstrates that alloys in this space may be readily selected to yield high wear resistance before and after a range of heat treatment cycles. Table 12: Wear Testing ResultsAustenitizing Temperature ( deg C)ASTM G65 Mass Loss (g)None (Standard Range)0.056 - 0.0908500.0788750.0819000.0809250.0739500.072

[0117] Ingots of an alloy according to the invention were compared to two commercially available chromium bearing alloys before and after an austenitizing and quenching cycle. Table 13 describes the hardness of each alloy before and after austenitizing at 900 degree C for 2 hours followed by and oil quench. The chemistries below are in weight percent with the balance iron. This chart demonstrates that alloys in this invention may have the same or similar hardness before and after a heat treat cycle. Table 13 demonstrates that the retention of hardness after heat treatment is not an inherent characteristic of hardfacing alloy comprising C and B. Table 13: Hardness before and after austenitizingAlloyInitial Hardness (HRC)Hardness after Quenching (HRC)BCCrMnMoNbNiSiTiVWQ#167671.92.40015.2501.50010.50Vecalloy 70064601.051.374.800.2005.000.500.502.010Vecalloy 752676241.0811.29112.253.400.51.500 Welding and Performance

[0118] Alloys described in this disclosure may have improved toughness, impact, and wear resistance over conventional hardfacing materials. The below Table 14 describes the testing results of two alloys according to the invention, I #1 and I #2, along with two commercially available and chromium bearing hardfacing materials, standard #1 and standard #2. These materials were welded using standard welding procedures to produce a deposit 25mm wide by 6 mm thick. The welded samples were then tested for hardness, wear resistance according to ASTM G65 testing, and impacts until failure when subjected to 20J of impact energy.

[0119] The wire feedstock designated as alloy I #1 has a nominal chemistry of B:1.8, C:2.2, Mn:1, Mo: 15, Ni: 1.5, Si:0.5, V:9.35, Fe: balance. Alloy I #2 wire has a nominal chemistry B:2.2, C:2.8, Mn:1, Mo:17.7, Ni:1.7, Si:0.5, V:12, Fe: balance. Standard #1 wire has a nominal chemistry of C:5.0, Cr:23, Mn:2.0, Si:1.0, Fe: balance. Standard #2 is sold commercially as SHS 9192 and has a measured chromium content using glow discharge spectroscopy of 16%. According to the data sheet of SHS 9192, the material has a chemistry of: Chromium < 20% Molybdenum < 10% Niobium < 10% Tungsten < 10% Aluminum < 5% Boron < 5% Carbon < 5% Manganese < 5% Silicon < 2% Iron Balance. Table 14 demonstrates that the disclosed impact resistance is not an inherent characteristic of hardfacing alloys. Table 14: Performance Testing ResultsAlloyWire Size (mm )Impact to Failur eAstm G65 (g loss)HR CVoltag eStickou t (in)AmperageWire Feed (in / min)Deposit width (mm)Thick ness (mm)I #11.698000.07265261.125220260256I #22.8105000.0666626.51.5430235256Standard #11.621950.1260261.125240260256Standard #21.69650.06265241.125200275256 Applications

[0120] The alloys described in this patent can be used in a variety of applications and industries. Some examples of applications of use include:

[0121] Surface Mining applications include the following components and coatings for the following components: Wear resistant sleeves and / or wear resistant hardfacing for slurry pipelines, mud pump components including pump housing or impeller or hardfacing for mud pump components, ore feed chute components including chute blocks or hardfacing of chute blocks, separation screens including but not limited to rotary breaker screens, banana screens, and shaker screens, liners for autogenous grinding mills and semi-autogenous grinding mills, ground engaging tools and hardfacing for ground engaging tools, wear plate for buckets and dumptruck liners, heel blocks and hardfacing for heel blocks on mining shovels, grader blades and hardfacing for grader blades, stacker reclaimers, sizer crushers, general wear packages for mining components and other comminution components.

[0122] Downstream oil and gas applications include the following components and coatings for the following components: Downhole casing and downhole casing, drill pipe and coatings for drill pipe including hardbanding, mud management components, mud motors, fracking pump sleeves, fracking impellers, fracking blender pumps, stop collars, drill bits and drill bit components, directional drilling equipment and coatings for directional drilling equipment including stabilizers and centralizers, blow out preventers and coatings for blow out preventers and blow out preventer components including the shear rams, oil country tubular goods and coatings for oil country tubular goods.

[0123] Upstream oil and gas applications include the following components and coatings for the following components: Process vessels and coating for process vessels including steam generation equipment, amine vessels, distillation towers, cyclones, catalytic crackers, general refinery piping, corrosion under insulation protection, sulfur recovery units, convection hoods, sour stripper lines, scrubbers, hydrocarbon drums, and other refinery equipment and vessels.

[0124] Pulp and paper applications include the following components and coatings for the following components: Rolls used in paper machines including yankee dryers and other dryers, calendar rolls, machine rolls, press rolls, digesters, pulp mixers, pulpers, pumps, boilers, shredders, tissue machines, roll and bale handling machines, doctor blades, evaporators, pulp mills, head boxes, wire parts, press parts, M.G. cylinders, pope reels, winders, vacuum pumps, deflakers, and other pulp and paper equipment,

[0125] Power generation applications include the following components and coatings for the following components: boiler tubes, precipitators, fireboxes, turbines, generators, cooling towers, condensers, chutes and troughs, augers, bag houses, ducts, ID fans, coal piping, and other power generation components.

[0126] Agriculture applications include the following components and coatings for the following components: chutes, base cutter blades, troughs, primary fan blades, secondary fan blades, augers, sugar cane harvesting, sugar cane milling operations, and other agricultural applications.

[0127] Construction applications include the following components and coatings for the following components: cement chutes, cement piping, bag houses, mixing equipment and other construction applications

[0128] Machine element applications include the following components and coatings for the following components: Shaft journals, paper rolls, gear boxes, drive rollers, impellers, general reclamation and dimensional restoration applications and other machine element applications

[0129] Steel applications include the following components and coatings for the following components: cold rolling mills, hot rolling mills, wire rod mills, galvanizing lines, continue pickling lines, continuous casting rolls and other steel mill rolls, and other steel applications.

[0130] The alloys described in this patent can be produced and or deposited in a variety of techniques effectively. Some examples of processes include:

[0131] Thermal spray process including those using a wire feedstock such as twin wire arc, spray, high velocity arc spray, combustion spray and those using a powder feedstock such as high velocity oxygen fuel, high velocity air spray, plasma spray, detonation gun spray, and cold spray. Wire feedstock can be in the form of a metal core wire, solid wire, or flux core wire. Powder feedstock can be either a single homogenous alloy or a combination of multiple alloy powder which result in the desired chemistry when melted together.

[0132] Welding processes including those using a wire feedstock including metal inert gas (MIG) welding, tungsten inert gas (TIG) welding, arc welding, submerged arc welding, open arc welding, bulk welding, laser cladding, and those using a powder feedstock including laser cladding and plasma transferred arc welding. Wire feedstock can be in the form of a metal core wire, solid wire, or flux core wire. Powder feedstock can be either a single homogenous alloy or a combination of multiple alloy powder which result in the desired chemistry when melted together.

[0133] Casting processes including processes typical to producing cast iron including sand casting, permanent mold casting, chill casting, investment casting, lost foam casting, die casting, centrifugal casting, glass casting, slip casting and process typical to producing wrought steel products including continuous casting processes.

[0134] Post processing techniques including rolling, forging, surface treatments such as carburizing, nitriding, carbonitriding, bonding, heat treatments including austenitizing, normalizing, annealing, stress relieving, tempering, aging, quenching, cryogenic treatments, flame hardening, induction hardening, differential hardening, case hardening, decarburization, machining, grinding, cold working, work hardening, and welding.

[0135] From the foregoing description, it will be appreciated that inventive products and approaches for chromium free and low-chromium alloys are disclosed.

[0136] Certain features that are described in this disclosure in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations, one or more features from a claimed combination can, in some cases, be excised from the combination, and the combination may be claimed as any subcombination or variation of any subcombination.

[0137] Conditional language, such as "can," "could," "might," or "may," unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include or do not include, certain features, elements, and / or steps. Thus, such conditional language is not generally intended to imply that features, elements, and / or steps are in any way required for one or more embodiments.

[0138] Conjunctive language such as the phrase "at least one of X, Y, and Z," unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z. Thus, such conjunctive language is not generally intended to imply that certain embodiments require the presence of at least one of X, at least one of Y, and at least one of Z.

[0139] Language of degree used herein, such as the terms "approximately," "about," "generally," and "substantially" as used herein represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms "approximately", "about", "generally," and "substantially" may refer to an amount that is within less than or equal to 10% of, within less than or equal to 5% of, within less than or equal to 1% of, within less than or equal to 0.1 % of, and within less than or equal to 0.01% of the stated amount. If the stated amount is 0 (e.g., none, having no), the above recited ranges can be specific ranges, and not within a particular % of the value. For example, within less than or equal to 10 wt. / vol. % of, within less than or equal to 5 wt. / vol. % of, within less than or equal to 1 wt. / vol. % of, within less than or equal to 0.1 wt. / vol. % of, and within less than or equal to 0.01 wt. / vol. % of the stated amount.

[0140] Some embodiments have been described in connection with the accompanying drawings. The figures are drawn to scale, but such scale should not be limiting, since dimensions and proportions other than what are shown are contemplated and are within the scope of the disclosed inventions. Distances, angles, etc. are merely illustrative and do not necessarily bear an exact relationship to actual dimensions and layout of the devices illustrated.

Claims

1. A low chromium or chromium-free ferrous alloy, wherein the alloy is formed into or configured to form a material comprising, under equilibrium solidification conditions at 1300K: a total mole fraction of transition metal borides and borocarbides of between 5 and 50 %, wherein a metallic portion of the transition metal borides and borocarbides comprises greater than or equal to 15 wt. % W+Mo; and a mole fraction of isolated carbides in the material between 5 and 40%, wherein isolated carbides are defined as MC type carbides having one or more of the following elements: V, Ti, Nb, Zr, Hf, W, Mo, wherein the alloy comprises in wt. %: B: 1.6 - 2.3 C: 2-3 Cr: 0 - 0.01 Mo: 13-20 Mn: 0 - 3 Ni: 0 - 3 Si: 0 - 1.5 V: 8 - 14; wherein the balance consists of Fe and incidental impurities.

2. The alloy of claim 1, wherein the isolated carbides have a metallic component greater than or equal to 50 wt. % vanadium.

3. The alloy of claim 1, wherein a mole fraction of an embrittling hard phase in the material comprising Fe2B, M23(C,B)6, M7(C,B)3, and M3(C,B) is less than or equal to 10% when measured at a matrix solidus temperature, wherein M is greater than or equal to 75 wt. % Fe.

4. The alloy of claim 1, wherein the metallic portion of the transition metal borides and borocarbides comprise greater than or equal to 35 wt. % W+Mo.

5. The alloy of claim 1, wherein an FCC-BCC transition temperature of the material under equilibrium solidification conditions is less than or equal to 1300K.

6. The alloy of claim 1, wherein a melt range of the material under equilibrium solidification conditions is less than or equal to 250 °C, melt range being defined as the difference between a formation temperature of a first hard phase to solidify and a matrix liquidus temperature.

7. The alloy of claim 1, wherein the material has a deposited hardness greater than or equal to 55HRC, and wherein a hardness of the material after austenitizing and quenching is greater than or equal to 55HRC.

8. A powder, wire, casting, and / or hardfacing layer for wear protection comprising the alloy of one of claims 1 to 7.

9. The alloy of claim 1, where the alloy comprises, in weight percent, Fe and: B: 1.64, C: 2, Mo: 13.6, V: 8.5; B: 1.8, C: 2.2, Mo: 15, V: 9.35; B: 2.2, C: 2.8, Mo: 17.7, V: 12; B: 2.05, C: 2.6, Mo: 16.3, V: 11.1; B: 1.64, C: 2, Mn: 1, Mo: 13.6, Ni: 1.3, Si: 0.5 V: 8.5; B: 1.8, C: 2.2, Mn: 1, Mo: 15, Ni: 1.5, Si: 0.5, V: 9.35; B: 2.2, C: 2.8, Mn: 1, Mo: 17.7, Ni: 1.7; Si: 0.5, V: 12; B: 2.05, C: 2.6, Mn: 1, Mo: 16.3, Ni: 1.6, Si: 0.5, V:11.1; B: 2.0, C: 2.8, Mo: 18, V: 13; B: 2.0, C: 2.8, Mo: 18, V: 11.5; B: 1.85, C: 2.6, Mo: 18, V: 12; B: 2.0, C: 2.8, Mn: 0.5, Mo: 18, Ni: 1.5, Si: 0.5, V: 13; B: 2.0, C: 2.8, Mn: 0.5, Mo: 18, Ni: 1.5, Si: 0.5, V: 11.5; or B: 1.85, C: 2.6, Mn: 0.5, Mo: 18, Ni: 1.5, Si: 0.5, V: 12.