Low nickel high manganese austenitic wear-resistant steel welding wire rod and welding wire

Abstract

The present invention relates to a low-nickel high-manganese austenitic wear-resistant steel welding wire rod containing Fe and inevitable impurity elements, and further containing the following chemical elements in the following mass percentage contents: C: 0.05 to 0.20%, Mn: 5.5 to 9.0%, Si: 0.2 to 1.0%, Cr: 16.0 to 21.0%, Ni: 3.0 to 5.0%, Nb: 0.10 to 0.17%, Ti: 0.10 to 0.20%, N: 0.12 to 0.17%, Mo: 0.80 to 1.25%. Furthermore, the present invention also relates to a low-nickel high-manganese austenitic wear-resistant steel welding wire, a manufacturing method of the low-nickel high-manganese austenitic wear-resistant steel welding wire rod, and a manufacturing method of the low-nickel high-manganese austenitic wear-resistant steel welding wire. The welding wire according to the present invention can form a fully austenitic weld zone during the welding process and matches the welding characteristics of the high-carbon high-manganese wear-resistant steel base material, so that the problem of cold cracking that may occur during the welding process of the high-carbon high-manganese austenitic wear-resistant steel can be avoided.

Description

Technical Field

[0001] The present invention relates to a welding wire and a welding wire, and in particular, to an austenitic wear-resistant steel welding wire and a welding wire.

Background Art

[0002] As is well known in the field of welding, in order to ensure the quality after welding, welding wire and welding wire designed according to the requirements in use are always the focus of attention in design by researchers.

[0003] The stainless steel welding wire included in the current ASME SFA5.9-5.9M "Technical Conditions for Stainless Steel Welding Wire and Filler Wire" standard used in the prior art is mainly used for stainless steel welding. In the design of the composition of the stainless steel welding wire, the focus is on the corrosion resistance matching the stainless steel.

[0004] Different from the design idea of such traditional stainless steel welding wire, the inventors of the present invention use and design a completely different alloy element composition system, and develop a new low-nickel high-manganese austenitic wear-resistant steel welding wire and welding wire to match the welding characteristics of the high-carbon high-manganese wear-resistant steel base material, thereby effectively avoiding the problem of cold cracking in the welding process of the high-carbon high-manganese austenitic wear-resistant steel, and expecting to ensure that the welded joint has excellent comprehensive performance.

[0005] In the current prior art, researchers in this field have already developed and designed many welding wire and welding wire that can meet the welding requirements of various types of steel materials, but have not disclosed the technical solution of the present invention. For example, in a Japanese patent document with a publication number of JP-A-2013-86134 and a publication date of May 13, 2013, it is possible to weld a high-strength steel with a tensile strength of 950 MPa without preheating, and it is possible to obtain a high-strength and high-toughness welded joint. A high-strength steel welding wire with a composition of C: 0.03 to 0.08%, Si: 0.2 to 1.0%, Mn: 0.3 to 3.0%, Ni: 4.0 to 7.0%, Cr: 11.5 to 15.0% is disclosed. Compared with the welding wire and welding wire designed according to the present invention, the technical solution of this patent is that the content of the main components Mn and Cr elements is outside the scope of the claims of the elements designed according to the present invention, and it does not contain stabilizing elements such as Ti and Nb.

[0006] Also, for example, in a patent document with a publication number of WO2013055700, a publication date of April 18, 2013, and a title of "WAFER LEVEL APPLIED RF SHIELDS", an austenitic welding wire with a chemical composition of C: 0.1%, Si: 0.8%, Mn: 1.5 to 5.5%, Ni: 8 to 15%, Cr: 18 to 24%, Al < 0.05%, N: 0.15 to 0.35% is disclosed.

[0007] Furthermore, for example, in a patent document with a publication number of WO2012157542, a publication date of July 31, 2014, and a title of "WELDING MATERIAL AND WELDED JOINT", a low-Mn high-Cr composition system design is adopted, and its chemical composition is C < 0.02%, Si < 2%, Mn < 2%, Cr: 26 to 50%, N < 0.15%, P < 0.02%, S < 0.002%, 5 ≤ Ni ≤ Cr - 14, and a welding wire for welding SUS310 stainless steel is disclosed.

Summary of the Invention

Problems to be Solved by the Invention

[0008] One object of the present invention is to provide a low-nickel high-manganese austenitic wear-resistant steel welding wire rod. By optimizing the design of the chemical element composition of the low-nickel high-manganese austenitic wear-resistant steel welding wire rod itself, the content of alloying elements is reduced, and it is ensured that the weld metal is a fully austenitic structure. Moreover, it is adapted to the welding characteristics of the high-carbon high-manganese wear-resistant steel base material, so as to obtain good plasticity, toughness and low-temperature crack resistance, and solve the problems of the large welding low-temperature crack tendency and poor welding quality stability of the conventional high-carbon content high-manganese austenitic wear-resistant steel.

Means for Solving the Problems

[0009] To achieve the above object, the present invention provides a low-nickel high-manganese austenitic wear-resistant steel welding wire rod containing Fe and inevitable impurity elements, and further containing the following chemical elements in the following mass percentage contents: C: 0.05 to 0.20%, Mn: 5.5 to 9.0%, Si: 0.2 to 1.0%, Cr: 16.0 to 21.0%, Ni: 3.0 to 5.0%, Nb: 0.10 to 0.17%, Ti: 0.10 to 0.20%, N: 0.12 to 0.17%, Mo: 0.80 to 1.25%.

[0010] Furthermore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, the mass percentage contents of its respective chemical elements are: C: 0.05 to 0.20%, Mn: 5.5 to 9.0%, Si: 0.2 to 1.0%, Cr: 16.0 to 21.0%, Ni: 3.0 to 5.0%, Nb: 0.10 to 0.17%, Ti: 0.10 to 0.20%, N: 0.12 to 0.17%, Mo: 0.80 to 1.25%; the balance is Fe and inevitable impurity elements.

[0011] In the above technical solution of the present invention, the present invention adopts a reasonable chemical composition design and adopts a low-nickel high-manganese Ni-Cr-Mn-Fe alloy system, so that a new austenitic wear-resistant steel welding wire rod can be designed. When designing the chemical composition, in the low-nickel high-manganese austenitic wear-resistant steel welding wire rod, by increasing the content of Mn element in the wire rod to replace the Ni element, it is ensured that the weld metal obtained by welding from the subsequently prepared welding wire has a fully austenitic structure, and at the same time, the advantage of low cost is obtained. Correspondingly, in the low-nickel high-manganese austenitic wear-resistant steel welding wire rod, Cr element is further added to obtain high strength; at the same time, a small amount of elements such as Ti, Nb, Mo, and N are also appropriately added.

[0012] In the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, the design principle of each chemical element is as follows: Mn: In the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, by controlling the mass percentage content of the Mn element, which is the main alloying element, in the range of 5.5-9.0%, it can be made equivalent to the composition of the high-manganese wear-resistant steel base material, and a composition system substantially the same as that of the base material can be ensured.

[0013] In the present invention, by adding high-manganese austenite-forming elements, stable austenite formation can be ensured in the welded joint, the transformation to martensite at low temperature can be prevented, and since there is no gradient change in the concentration of the Mn element, the sudden change in the structure and performance of the fusion zone of the welded joint can also be avoided. Moreover, the addition of a high content of the Mn element can also increase the solubility of the N element in austenite, and Mn is more likely to combine with S than Fe. When a sufficient amount of Mn is added, stable MnS can be formed, and the problem of high-temperature cracking of the welding wire rod that may occur in the welding process can be effectively eliminated.

[0014] C: In the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, the inventors promote the formation of fine and dispersed carbides with other elements by increasing the content of C element, and improve the strength of the welded joint formed by the welding wire during welding, so as to meet the requirements for the welding applications of wear-resistant steel in fields such as mining machinery and civil engineering machinery manufacturing. The present invention can ensure the high strength of the welded part and improve the toughness of the welded structure by combining the contents of Cr element and C element, thereby effectively preventing the load fracture of the wear-resistant steel welded structure. Therefore, in order to exert the beneficial effect of C element, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, the mass percentage content of C element is controlled to be 0.05-0.20%.

[0015] Si: In the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, Si is an important deoxidizing element that can play a deoxidizing role. At the same time, by adding an appropriate amount of Si element to the welding wire, the fluidity of the molten metal can be improved, and the occurrence of welding defects can also be suppressed. However, it should be noted that if the Si content is too high, intermetallic compounds represented by σ phase are likely to be generated, so the Si element content in the welding wire should not be too high. Therefore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, the mass percentage content of Si element is controlled to be 0.2-1.0%. In some embodiments, the Si content is 0.4-0.8%.

[0016] Cr: In the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, Cr is an important solid-solution strengthening element. The Cr element can dissolve in the matrix, cause lattice distortion, and generate an elastic stress field; at the same time, the Cr element can reduce the solid-solution volume layer defect energy to a certain extent and can also greatly improve the strength of the welded part. In order to ensure the solid-solution strengthening ability of the weld metal and match the strength, it is necessary to control the Cr element content in the welding wire rod to be 16.0% or more; however, when the Cr element content exceeds 21.0%, intermetallic compounds represented by the σ phase are formed at the center of the welded part, leading to a decrease in welding performance and deterioration of the toughness of the welded part. Therefore, it is necessary to pay attention that the Cr element content should not be too high. Therefore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, the mass percentage content of the Cr element is controlled to be 16.0 - 21.0%.

[0017] Ni: In the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, Ni is an austenite-forming element together with C and Mn. Due to the combined action of these three elements, the molten pool of the welded part can solidify with austenite as the initial phase and ensure the formation of an austenitic welding structure at room temperature. At the same time, by adding the Ni element to the welding wire rod, the C content can be reduced, and the toughness and plasticity of the welded part can be improved. Therefore, considering the use requirements of low-cost welding wire and also taking into account the plasticity and toughness indexes of the weld metal, in the present invention, the mass percentage content of the Ni element is controlled to be 3.0 - 5.0%.

[0018] Nb, Ti: In order to ensure the refinement of the solidification structure of the weld metal during the welding process of high-manganese wear-resistant steel, in the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, the inventors also added Ti and Nb, which are important elements for the refinement of the weld metal, to the chemical composition system of the welding wire rod.

[0019] The Ti element and the Nb element form carbides and nitrides of Ti and Nb in the welded part, disperse and precipitate as particles, and become the solidification nuclei of the ferrite phase. Therefore, the structure of the weld metal is refined, and the strength and toughness of the welded joint are effectively improved. However, if the contents of the Ti element and the Nb element are too high, it will lead to a decrease in the plasticity and toughness of the welded part. Therefore, it is necessary to pay attention that the contents of the Ti and Nb elements in the welding wire rod should not be too high. Therefore, as a result of summarizing the comprehensive effects of each element in the present invention, in the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, the mass percentage content of the Nb element is controlled to be 0.10 to 0.17%, and the mass percentage content of the Ti element is controlled to be 0.10 to 0.20%.

[0020] N: In the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, N is a strong solid solution strengthening element and also a strong austenite forming element. Considering that a predetermined amount of N element is required to meet the requirement that the desired weld metal to be formed in the present invention has a fully austenitic structure, and to combine with the Ti element and the Nb element to form nitride particles and meet the requirement of refining the weld metal structure, in the present invention, it is necessary to add the N element with a content of 0.12% or more. However, if the N element is contained in excess, blowholes will occur as welding defects, and during the welding process, excessive N is likely to generate nitrides, leading to a decrease in the toughness and corrosion resistance of the steel. Therefore, the content of the N element in the welding wire rod should not be too high. Therefore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention, the mass percentage content of the N element is controlled to be 0.12 to 0.17%.

[0021] Mo: In the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, by adding Mo element, the stability of carbides can be improved, and the strength of the weld metal can be improved. In addition, the Mo element forms complex cementite with Fe and C elements, and can improve the ductility, toughness and wear resistance of the welded part. Therefore, in order to exert the beneficial effects of the Mo element, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, the mass percentage content of the Mo element is controlled to be 0.80-1.25%.

[0022] Furthermore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, among the inevitable impurity elements, P≤0.002% and S≤0.001%.

[0023] In the above technical solution, both P and S elements are impurity elements in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention. Technically, as long as it is permitted, in order to obtain steel materials with better performance and better quality, the content of impurity elements in the welding wire should be reduced as much as possible.

[0024] In the present invention, the presence of impurity elements S and P increases the risk of liquation cracking and reheat cracking of the weld metal. Therefore, in the present invention, it is necessary to strictly control the content of S and P elements so that S≤0.001% and P≤0.002%. At the same time, by minimizing the content of S and P through composition control, the formation of low-melting eutectics in the weld metal can be avoided, and the tendency of high-temperature cracking of the welded part can be reduced.

[0025] Furthermore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, its weld metal is a fully austenitic structure.

[0026] Furthermore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, the performance of its weld metal is that the elongation rate at room temperature (about 20°C) is 22-30%, and the impact toughness at room temperature is 90-143 J / cm2 It satisfies the condition that the yield strength is 681 to 720 MPa and the tensile strength is 790 to 853 MPa.

[0027] Correspondingly, another object of the present invention is to provide a low-nickel high-manganese austenitic wear-resistant steel welding wire. The low-nickel high-manganese austenitic wear-resistant steel welding wire does not require a preheating and post-weld heat treatment process during the welding process, can reduce the welding difficulty, and can also save the cost of heat treatment, having the advantage of low cost.

[0028] To achieve the above object, the present invention provides a low-nickel high-manganese austenitic wear-resistant steel welding wire manufactured using the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to the present invention. Specifically, the chemical element composition of the welding wire according to the present invention is the same as that of the low-nickel high-manganese austenitic wear-resistant steel welding wire rod, contains Fe and inevitable impurity elements, and further contains the following chemical elements in the following mass percentage contents: C: 0.05 to 0.20%, Mn: 5.5 to 9.0%, Si: 0.2 to 1.0%, Cr: 16.0 to 21.0%, Ni: 3.0 to 5.0%, Nb: 0.10 to 0.17%, Ti: 0.10 to 0.20%, N: 0.12 to 0.17%, Mo: 0.80 to 1.25%. Furthermore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, the mass percentage contents of its respective chemical elements are: C: 0.05 to 0.20%, Mn: 5.5 to 9.0%, Si: 0.2 to 1.0%, Cr: 16.0 to 21.0%, Ni: 3.0 to 5.0%, Nb: 0.10 to 0.17%, Ti: 0.10 to 0.20%, N: 0.12 to 0.17%, Mo: 0.80 to 1.25%; the balance is Fe and inevitable impurity elements.

[0029] In the above technical solution of the present invention, the manufactured low-nickel high-manganese austenitic wear-resistant steel welding wire has a weld metal with a fully austenitic structure, can form a fully austenitic weld in the welding process, and is adapted to the welding characteristics of the high-carbon high-manganese wear-resistant steel base material. Therefore, it can be applied to the welding of the high-carbon high-manganese austenitic wear-resistant steel body, and can avoid the problem of cold cracking that may occur in the welding process of the high-carbon high-manganese austenitic wear-resistant steel.

[0030] Furthermore, in the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention, the performance of its weld metal has an elongation rate of 22-30% at room temperature (about 20°C), an impact toughness of 90-143 J / cm at room temperature 2 and satisfies the conditions that the yield strength is 681-720 MPa and the tensile strength is 790-853 MPa.

[0031] Of course, the low-nickel high-manganese austenitic wear-resistant steel welding wire designed according to the present invention has very wide applicability, not limited to the welding of high-carbon high-manganese austenitic wear-resistant steel. In some embodiments, it can also be effectively applied to the welding of dissimilar steels such as martensite-bainite strengthened wear-resistant steel, structural steel, and cast steel.

[0032] Furthermore, the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention is applicable to gas-shielded arc welding with a consumable electrode.

[0033] Furthermore, the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention is not preheated during the welding process.

[0034] Furthermore, the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention is not post-weld heat-treated during the welding process.

[0035] The low-nickel high-manganese austenitic wear-resistant steel welding wire and welding wire according to the present invention have the following advantages and beneficial effects compared with the prior art: In the present invention, the inventors adopted a composition system design of low nickel and high manganese, and controlled the content of the main alloying element Mn element in the range of 5.5 to 9.0%, so as to ensure that the obtained welding wire and welding wire have substantially the same composition system as the high-carbon high-manganese austenitic wear-resistant steel base material. Also, in the design of the chemical composition, by adding Mn in a high content and also controlling the P and S elements, the tendency of hot cracking in the welding process could be effectively avoided.

[0036] Correspondingly, in this low-nickel high-manganese austenitic wear-resistant steel welding wire designed according to the present invention, by substituting Ni with Mn, the cost of the alloy could be effectively reduced. At the same time, the low-nickel high-manganese austenitic wear-resistant steel welding wire manufactured using the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention does not require a preheating and post-weld heat treatment process during the welding process, can reduce the welding difficulty, and can also save the cost of heat treatment, having the advantage of low cost.

[0037] Also, the low-nickel high-manganese austenitic wear-resistant steel welding wire has a fully austenitic structure in the weld metal, can form a fully austenitic weld in the welding process, and matches the welding characteristics of the high-carbon high-manganese wear-resistant steel base material, so it has good plasticity, toughness and low-temperature crack resistance, and can solve the problems of a large tendency of low-temperature cracking in welding and poor welding quality stability of the high-carbon high-manganese austenitic wear-resistant steel. The welding wire and the weld metal formed by the welding wire of the low-nickel high-manganese austenitic wear-resistant steel have a yield strength in the range of 681 to 720 MPa, a tensile strength in the range of 790 to 853 MPa, an elongation rate at room temperature in the range of 22 to 30%, and an impact toughness at room temperature in the range of 90 to 143 J / cm 2 and can meet the requirements of strength, plasticity and toughness of wear-resistant mining machinery equipment made of high-carbon high-manganese wear-resistant steel.

[0038] In practice, the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the present invention can be applied to the welding of the high-carbon high-manganese austenitic wear-resistant steel body, and can avoid the problem of low-temperature cracking that may occur during the welding process of the high-carbon high-manganese austenitic wear-resistant steel.

[0039] Of course, this low-nickel high-manganese austenitic wear-resistant steel welding wire designed according to the present invention has very wide applicability. It is not limited to the welding of high-carbon high-manganese austenitic wear-resistant steel. In some embodiments, it can also be effectively applied to the welding of dissimilar steels such as martensite-bainite strengthened wear-resistant steel, structural steel, and cast steel.

[0040] The present invention also provides a method for manufacturing the above-mentioned low-nickel high-manganese austenitic wear-resistant steel welding wire, which includes smelting the components described in the text and then rolling and solution-treating the wire slab obtained by smelting. In the rolling process, the in-furnace heating temperature of the wire slab may be 930 - 1160°C, the out-of-furnace temperature of the wire slab may be 1080 - 1160°C, the rolling start temperature may be 1000 - 1080°C, the rolling end temperature is ≥900°C (for example, 900 - 980°C), the rolling speed may be 60 - 75 m / s, and the cooling method after rolling may be air cooling and / or water cooling. The solution temperature may be 1040 - 1120°C, the holding time may be 40 minutes to 60 minutes, and the cooling method after solution is water cooling.

[0041] By using the well-known drawing process in this field to draw the above-mentioned wire, the welding wire according to the present invention can be manufactured. An exemplary drawing process is to perform stress relief treatment at 890 - 910°C as needed, then air cool, and finally form the welding wire by a single drawing.

Embodiments for Carrying Out the Invention

[0042] The following will further interpret and explain the low-nickel high-manganese austenitic wear-resistant steel welding wire and welding wire according to the present invention based on specific embodiments. However, such interpretation and explanation shall not unduly limit the technical solution of the present invention.

[0043] Examples 1 to 6 The low-nickel high-manganese austenitic wear-resistant steel welding wires according to Examples 1 to 6 of the present invention were all manufactured through the following steps: (1) Smelting and rolling were carried out according to the chemical compositions shown in Table 1 to obtain the low-nickel high-manganese austenitic wear-resistant steel welding wire rods according to Examples 1 to 6. The main points of the manufacturing process of the welding wire rods were that the in-furnace heating temperature of the wire rod slabs was 930 - 1160°C, the tapping temperature of the wire rod slabs was 1080 - 1160°C, the rolling start temperature was 1000 - 1080°C, the rolling end temperature was ≥900°C, the rolling speed was 60 - 75 m / s, air cooling was performed after rolling, the solution treatment temperature was 1040 - 1120°C, the holding time was 40 minutes - 60 minutes, and the cooling method after solution treatment was water cooling. The specific process is shown in Table 2.

[0044] (2) Drawing: The main process control parameters were stress relief treatment at 890 - 910°C, air cooling, and finally forming the low-nickel high-manganese austenitic wear-resistant steel welding wires according to Examples 1 to 6 by single-pass drawing, and controlling the diameter of the welding wire to 1.2 mm.

[0045] In the present invention, the inventors have not particularly limited the smelting, rolling, and drawing processes in the above manufacturing process. The operator can select and implement the general processes known in the art based on the designed chemical composition adopted, and obtain the low-nickel high-manganese austenitic wear-resistant steel welding wire rods and welding wires according to Examples 1 to 6.

[0046] It should be noted that the design of the chemical compositions of the low-nickel high-manganese austenitic wear-resistant steel welding wire rods and welding wires according to Examples 1 to 6 all met the requirements of the specifications designed by the present invention.

[0047] The mass percentage ratios of the chemical elements of the low-nickel high-manganese austenitic wear-resistant steel welding wire and welding wire according to Examples 1 to 6 are shown in Table 1.

[0048]

Table 1

[0049] The manufacturing processes of the respective examples are shown in Table 2.

[0050]

Table 2

[0051] Samples were respectively taken from the low-nickel high-manganese austenitic wear-resistant steel welding wires of Examples 1 to 6 of the finished products with a diameter of 1.2 mm obtained through the above processes and steps. Specifically, the electrode type gas shielded welding method was adopted for clad welding. However, in the welding process, the low-nickel high-manganese austenitic wear-resistant steel welding wire samples according to Examples 1 to 6 of the present invention did not require preheat treatment and post-weld heat treatment.

[0052] In order to verify the excellent performance of the weld metal obtained by welding from the low-nickel high-manganese austenitic wear-resistant steel welding wires according to Examples 1 to 6, the inventors further sampled from the weld metal obtained by welding from the low-nickel high-manganese austenitic wear-resistant steel welding wires according to Examples 1 to 6. For the weld metal obtained in each example, the microstructure was observed and the mechanical properties were measured. The measurement results of the mechanical properties are shown in Table 2 below.

[0053] The measuring means for the related performance was as follows: (1) Tensile property measurement: A tensile test was carried out using GB / T 228.1-2010, and the yield strength, tensile strength, and elongation of the welded metal obtained by welding from the low-nickel high-manganese austenitic wear-resistant steel welding wire according to Examples 1 to 6 were measured. However, when performing the tensile test, for the accuracy of the measurement, two measurements were carried out for each example, and the average value of the two measurements was taken as the final result.

[0054] (2) Impact property measurement: An impact test was carried out using GB / T 229-2007, and the impact toughness at room temperature of the welded metal obtained by welding from the low-nickel high-manganese austenitic wear-resistant steel welding wire according to Examples 1 to 6 was measured. However, when performing the impact test on the welded metal according to each example, for the accuracy of the measurement, three measurements were carried out for each example, and the average value of the three measurements was taken as the impact toughness value which is the final result.

[0055] The observation results and the measurement results of the mechanical properties of the welded metal obtained by welding from the low-nickel high-manganese austenitic wear-resistant steel welding wire according to Examples 1 to 6 are shown in Table 3.

[0056]

Table 3

[0057] As can be seen from Table 3 above, in the present invention, the welded metals obtained by welding from the low-nickel high-manganese austenitic wear-resistant steel welding wire according to Examples 1 to 6 are all in a fully austenitic structure, and all of these welded metals have excellent mechanical properties. Their yield strengths are in the range of 681.5 - 717 MPa, their tensile strengths are in the range of 799 - 852 MPa, the elongation at room temperature is in the range of 22.8 - 30%, and the impact toughness at room temperature is 90 J / cm 2 as above.

[0058] It is necessary to explain that the low-nickel high-manganese austenitic wear-resistant steel welding wire according to the above Examples 1 to 6 of the present invention is obtained by further drawing from the low-nickel high-manganese austenitic wear-resistant steel welding wire rods according to Examples 1 to 6 obtained in the step (1) according to the present invention. Therefore, it can be understood that the structure and performance of the above-mentioned weld metal are the same as those of the weld metal obtained from the low-nickel high-manganese austenitic wear-resistant steel welding wire rods according to each example.

[0059] As can be seen from the above, the low-nickel high-manganese austenitic wear-resistant steel welding wire manufactured by the technical solution of the present invention ensures the formation of stable austenite at the welded part, has good plasticity, toughness and low-temperature crack resistance, and solves the problems of large welding low-temperature crack tendency and poor welding quality stability of high-manganese austenitic wear-resistant steel with high carbon content.

[0060] At the same time, the weld metal obtained by welding from the low-nickel high-manganese austenitic wear-resistant steel welding wire can meet the requirements of strength, plasticity and toughness of wear-resistant mining machinery equipment made of high-carbon high-manganese wear-resistant steel. At the same time, good plasticity, toughness and low-temperature crack resistance of the weld metal under the process conditions without preheating and post-heating can be ensured.

[0061] In practical application, the low-nickel high-manganese austenitic wear-resistant steel welding wire designed according to the present invention can be mainly applied to the welding of the main body of high-manganese austenitic wear-resistant steel. Of course, in some embodiments, it can also be applied to the welding of dissimilar steels such as martensite-bainite type strengthened wear-resistant steel, structural steel, and high-strength cast steel.

[0062] In this low-nickel high-manganese austenitic wear-resistant steel welding wire designed according to the present invention, by substituting Ni element with Mn element, the cost of the alloy can be effectively reduced. Furthermore, this low-nickel high-manganese austenitic wear-resistant steel welding wire does not require a preheating and post-weld heat treatment process during the welding process, further reducing the difficulty of welding, saving the cost of heat treatment, and having the advantage of low cost.

[0063] In addition, the combination of each technical feature in this application is not limited to the combination described in the claims of this application or the combination described in the specific embodiments. As long as there is no contradiction between them, all the technical features described in this application can be freely combined or combined in any form.

[0064] Furthermore, it should also be noted that the above-mentioned embodiments are only specific embodiments of the present invention. The present invention is not limited to the above-mentioned embodiments, and it is obvious that any similar changes or deformations that can be directly derived or easily conceived by those skilled in the art from the disclosure content of the present invention are included in the protection scope of the present invention.

Claims

1. Containing Fe and inevitable impurity elements, and further containing the following chemical elements in the following mass percentage contents: C: 0.05 - 0.20%, Mn: 5.5 - 9.0%, Si: 0.2 - 1.0%, Cr: 16.0 - 21.0%, Ni: 3.0 - 5.0%, Nb: 0.10 - 0.17%, Ti: 0.10 - 0.20%, N: 0.12 - 0.17%, Mo: 0.80 - 1.25%; a low-nickel high-manganese austenitic wear-resistant steel welding wire rod characterized by containing these elements.

2. The mass percentage contents of its respective chemical elements are: C: 0.05 - 0.20%, Mn: 5.5 - 9.0%, Si: 0.2 - 1.0%, Cr: 16.0 - 21.0%, Ni: 3.0 - 5.0%, Nb: 0.10 - 0.17%, Ti: 0.10 - 0.20%, N: 0.12 - 0.17%, Mo: 0.80 - 1.25%; the balance being Fe and inevitable impurity elements; the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to Claim 1.

3. Among the inevitable impurity elements, P ≤ 0.002% and S ≤ 0.001%; the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to Claim 1 or 2.

4. The deposited metal is a fully austenitic structure; the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to Claim 1 or 2.

5. The performance of the welded metal is such that the elongation at room temperature is 22 - 30%, the impact toughness at room temperature is 90 - 143 J / cm ２ and it satisfies the conditions that the yield strength is 681 - 720 MPa and the tensile strength is 790 - 853 MPa. The low-nickel high-manganese austenitic wear-resistant steel welding wire according to claim 1 or 2 is characterized by this.

6. A low-nickel high-manganese austenitic wear-resistant steel welding wire manufactured using the low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to any one of Claims 1 to 5.

7. Characterized by being applicable to gas-shielded arc welding; the low-nickel high-manganese austenitic wear-resistant steel welding wire according to Claim 6.

8. Characterized by not being preheated during the welding process; the low-nickel high-manganese austenitic wear-resistant steel welding wire according to Claim 6.

9. Characterized by not being post-weld heat-treated during the welding process; the low-nickel high-manganese austenitic wear-resistant steel welding wire according to Claim 6.

10. A method for manufacturing a low-nickel high-manganese austenitic wear-resistant steel welding wire rod according to any one of Claims 1 to 5, including smelting the components according to any one of Claims 1 to 3, and then rolling and solution-treating the wire rod slab obtained from the smelting.

11. In the rolling process, the in-furnace heating temperature of the wire slab is 930 to 1160 °C, the tapping temperature of the wire slab is 1080 to 1160 °C, the rolling start temperature is 1000 to 1080 °C, the rolling end temperature is ≥ 900 °C, the rolling speed is 60 to 75 m / s, and it is characterized by air cooling after rolling. The method according to claim 10.

12. In the solution treatment process, the solution treatment temperature is 1040 to 1120 °C, the holding time is 40 minutes to 60 minutes, and the cooling method after solution treatment is water cooling. The method according to claim 10.

13. The method for manufacturing a low-nickel high-manganese austenitic wear-resistant steel welding wire according to any one of claims 6 to 9, characterized by including drawing the low-nickel high-manganese austenitic wear-resistant steel welding wire according to any one of claims 1 to 5.

14. The drawing includes performing stress relief treatment at 890 to 910 °C, then air cooling, and finally forming the welding wire by a single drawing. The method according to claim 13.

Images