阅读说明：本技术 一种适用于型钢粗轧工作辊堆焊修复用的高硬度、高韧性合金药芯焊丝 (High-hardness and high-toughness alloy flux-cored wire suitable for surfacing repair of rough-rolled working roll of profile steel ) 是由 赵云志 安达 安士合 陈静良 赵松 刘班 赵力 曾宪国 于 2019-11-22 设计创作，主要内容包括：本发明提供了一种适用于型钢粗轧工作辊堆焊修复用的高硬度、高韧性合金药芯焊丝,由外皮和药芯组成,所述药芯由以下原料制备得到：每100重量份药芯中包括：碳化铬、钼铁、铌铁、镍、锰、钛铁、铝镁合金、稀土硅铁和铁。本申请提供的型钢粗轧工作辊堆焊修复用的高硬度、高韧性合金药芯焊丝,其在Cr5合金系中合理调整Mo、Nb、Ni、N、RE等合金比例,通过微合金化以及合金原料含量的配比,保证了堆焊层合金具有高硬度、高耐磨性的同时,还具有很好的韧性和耐冷热疲劳性能。(The invention provides a high-hardness and high-toughness alloy flux-cored wire suitable for surfacing repair of a rough rolling working roll of section steel, which consists of a sheath and a flux core, wherein the flux core is prepared from the following raw materials: every 100 weight parts of the medicine core comprises: chromium carbide, ferromolybdenum, ferroniobium, nickel, manganese, ferrotitanium, aluminum magnesium alloy, rare earth ferrosilicon and iron. The application provides a high rigidity, high tenacity alloy flux-cored wire for surfacing repair of shaped steel rough rolling working roll, its reasonable adjustment Mo, Nb, Ni, N, RE etc. alloy proportion in Cr5 alloy system, through microalloying and the proportion of alloy raw materials content, when having guaranteed that surfacing layer alloy has high rigidity, high wearability, still has fine toughness and cold and hot fatigue resistance ability.)

1. The high-hardness and high-toughness alloy flux-cored wire suitable for the surfacing repair of the rough rolling working roll of the section steel consists of a sheath and a flux core, and is characterized in that the flux core is prepared from the following raw materials: every 100 weight parts of the medicine core comprises:

2. the flux-cored welding wire of claim 1, wherein the flux core is 30 to 40 wt% of the flux-cored welding wire.

3. The flux-cored wire of claim 1, wherein the chromium carbide comprises 12 to 14 wt% of C, 84 to 87 wt% of Cr, P < 0.025 wt%, and S < 0.025 wt%; the content of Mo in the ferromolybdenum is 60-65 wt%, P is less than 0.025 wt%, and S is less than 0.025 wt%; the content of Nb in the ferrocolumbium is 60-70 wt%, P is less than 0.025 wt%, and S is less than 0.025 wt%.

4. The flux-cored wire according to claim 1 or 3, wherein the grain size of the chromium carbide is 120 to 200 mesh, the grain size of the ferromolybdenum is 120 to 200 mesh, and the grain size of the ferroniobium is 160 to 300 mesh.

5. The flux-cored wire of claim 1, wherein the sheath is a low-carbon steel H08A steel strip with a thickness of 0.5-0.8 mm and a width of 12-16 mm.

6. The flux cored welding wire of claim 5, wherein the diameter of the flux cored welding wire is 2.4mm, 2.8mm, 3.2mm, or 4.0 mm.

7. The flux-cored wire of claim 1, wherein the core contains C in an amount of 0.60 to 0.80 wt%, Si in an amount of 0.90 to 1.05 wt%, Mn in an amount of 1.10 to 1.30 wt%, Cr in an amount of 5.50 to 7.00 wt%, Ni in an amount of 0.50 to 0.70 wt%, Mo in an amount of 2.00 to 2.20 wt%, Nb in an amount of 2.10 to 4.50 wt%, RE in an amount of < 1.5 wt%, and Fe in balance.

8. The flux-cored wire of claim 7, wherein (Cr + Mo)/Nb is 2.5 to 3.0.

Technical Field

The invention relates to the technical field of welding materials, in particular to a high-hardness and high-toughness alloy flux-cored wire suitable for surfacing repair of a rough rolling working roll of profile steel.

Background

The roller is one of main consumption spare parts in steel rolling production, and with the development of metallurgical technology, the steel rolling types are increased, the steel rolling speed and the automation degree are improved, and higher requirements are provided for the quality of the roller, particularly the strength, the toughness and the wear resistance of the roller. In recent years, the development trend of the material of the roller is towards high alloy and multi-element alloy, so that the difficulty of manufacturing the roller is increased.

The surfacing composite manufacturing by utilizing the worn and scrapped roller is a very valuable project with environmental protection, energy saving and high cost, and the technology is developed and applied rapidly in various steel mills along with the wide application of flux-cored wires, submerged arc welding equipment and submerged arc welding processes.

The flux-cored wire for repairing the metallurgical hot roller by surfacing mainly adopts Cr5 and Cr13 base alloy systems, and then different alloys such as Mo, W, V, Co, Nb and the like are added for strengthening, the hardness of the surfacing layer is HRc50 or so, the working requirement of the rolling mill can be basically met after the surfacing roller is installed on the machine, but the surfacing layer has unsatisfactory wear resistance and mainly has insufficient toughness of the surfacing layer; this is because when the hardness of the surfacing working layer is more than 50HRc, the toughness of the material is greatly reduced, and the roller is easy to crack or peel off during surfacing or use.

How to solve the problem of toughness of Cr5 and Cr13 surfacing materials is a difficult problem for researchers of surfacing materials.

Disclosure of Invention

The invention aims to provide a flux-cored welding wire for hot roll surfacing with high hardness, high wear resistance and high toughness.

The application provides a high-hardness and high-toughness alloy flux-cored wire suitable for pile-up welding repair of a rough-rolled working roll of section steel, which is prepared from chromium carbide, ferromolybdenum, ferroniobium, nickel, manganese, ferrotitanium, aluminum-magnesium alloy, rare earth ferrosilicon and iron; the flux-cored wire is reinforced by C, Cr, Mo, Nb and N, the structure of the obtained surfacing layer is high-carbon martensite based, carbon, nitride and a small amount of ferrite are uniformly dispersed, the structure purity is high, and crystal grains are fine and uniform, so that the flux-cored wire enables the surfacing layer alloy to have the advantages of high hardness, good wear resistance, good cold and hot fatigue resistance and excellent crack resistance. The steel passing amount of the hot-rolled rail beam roller which is built up by the welding wire reaches 5.7 ten thousand tons, which is 2 to 3 times of that of the common Cr5 series alloy (as shown in figures 1 and 2).

Drawings

FIG. 1 is a photograph of wear failure (2.0 million tons per steel) of a BD1 roller at a third hole location for a flux cored weld overlay made using comparative example 4;

FIG. 2 is a photograph of a wear failure (5.7 million tons per steel) of a BD1 roller third hole location of a flux cored weld overlay produced using example 2 of the present invention;

FIG. 3 is a photograph of the microstructure of a weld overlay made in example 2 of the present invention.

Detailed Description

Aiming at the problem of toughness of Cr5 and Cr13 series surfacing materials in the prior art, the application provides a high-hardness and high-toughness alloy flux-cored wire suitable for surfacing repair of a rough rolling working roll of profile steel, alloy proportions of Mo, Nb, Ni, N, RE and the like are reasonably adjusted in a Cr5 alloy system, and the alloy flux-cored wire also has good toughness and cold and hot fatigue resistance while ensuring that the surfacing layer alloy has high hardness and high wear resistance through microalloying and adjustment of alloy raw materials. Specifically, the high-hardness and high-toughness alloy flux-cored wire for the surfacing repair of the rough-rolled working roll of the section steel consists of a sheath and a flux core, wherein the flux core is prepared from the following raw materials: every 100 weight parts of the medicine core comprises:

as is well known to those skilled in the art, the flux-cored wire is composed of a sheath and a flux core, and the flux-cored wire is drawn by a wire drawing machine after being formed into an "O" shape by overlapping and then using a linear multi-pass drawing device. In the present application, the diameter of the flux cored wire is 2.4mm, 2.8mm, 3.2mm, or 4.0 mm. The sheath is well known to those skilled in the art, and more specifically, the sheath is a low-carbon steel H08E steel strip with a thickness of 0.5-0.8 mm and a width of 12-16 mm.

Specifically, the drug core is prepared from the following raw materials: chromium carbide, ferromolybdenum, ferroniobium, nickel, manganese, ferrotitanium, aluminum magnesium alloy, rare earth ferrosilicon and iron.

The chromium carbide content is 15-25 parts by weight, in a specific embodiment, 18-23 parts by weight, and in a specific embodiment, 20-22 parts by weight. The chromium carbide contains 12-14 wt% of C, 84-87 wt% of Cr, less than 0.025 wt% of P and less than 0.025 wt% of S. The granularity of the chromium carbide is 120-200 meshes.

The content of ferromolybdenum is 5-7 parts by weight, and specifically, the content of ferromolybdenum can be 5.2 parts by weight, 5.4 parts by weight, 5.9 parts by weight, 6.0 parts by weight, 6.4 parts by weight or 6.7 parts by weight. The content of Mo in the ferromolybdenum is 60-65 wt%, P is less than 0.025 wt%, and S is less than 0.025 wt%. The particle size of the ferromolybdenum is 120-200 meshes.

The content of the ferrocolumbium is 12-18 parts by weight, and specifically, the content of the ferrocolumbium is 14-17 parts by weight. The content of Nb in the ferrocolumbium is 60-70 wt%, P is less than 0.025 wt%, and S is less than 0.025 wt%. The particle size of the ferrocolumbium is 160-300 meshes.

The nickel is metal nickel, and the content of the nickel is 0.5-1.0 part by weight, specifically, the content of the nickel is 0.6-0.9 part by weight, and in a specific embodiment, the content of the nickel is 0.7-0.8 part by weight.

The manganese is metal manganese, and the content of the manganese is 5-7 parts by weight, specifically 5.3 parts by weight, 5.5 parts by weight, 5.9 parts by weight or 6.5 parts by weight.

The content of the ferrotitanium is 4-6 parts by weight, and specifically, the content of the ferrotitanium is 4.3 parts by weight, 4.8 parts by weight, 5.5 parts by weight, 5.8 parts by weight or 5.9 parts by weight.

The content of the aluminum magnesium alloy is 1-2 parts by weight, and specifically, the content of the aluminum magnesium alloy is 1.3 parts by weight, 1.5 parts by weight or 1.8 parts by weight.

The content of rare earth ferrosilicon is 1-2 parts by weight, specifically, the content of rare earth ferrosilicon is 1.2 parts by weight, 1.5 parts by weight, 1.6 parts by weight, 1.8 parts by weight or 1.9 parts by weight.

The components are used as raw materials for preparing the medicine core, and the medicine core comprises the following components in percentage by weight on the basis of the components: 0.60-0.80 wt% of C, 0.90-1.05 wt% of Si, 1.10-1.30 wt% of Mn, 5.50-7.00 wt% of Cr, 0.50-0.70 wt% of Ni, 2.00-2.20 wt% of Mo, 2.10-4.50 wt% of Nb, less than 1.5 wt% of RE, and the balance Fe.

Among the above components, (Cr + Mo)/Nb is preferably 2.5 to 3.0, and when (Cr + Mo)/Nb is greater than 3, the strengthening effect of Nb is insufficient, and when (Cr + Mo)/Nb is less than 2.5, carbon in the alloy is taken away by Nb, NbC increases, W7C3 decreases greatly, and the hardness of the overlay alloy decreases on the contrary.

In the flux-cored wire, the content of the flux core is 30-40 wt%, and more specifically, the content of the flux core is 32-37 wt%.

When the flux-cored wire is used for surfacing, the flux-cored wire is matched with a high-alkalinity flux, the obtained surfacing layer is low in P, S, O, H content, the structure is a high-carbon martensite base and carbon, nitride and a small amount of ferrite which are uniformly dispersed (as shown in figure 3), and as can be seen from figure 3, the microstructure is fine and uniform in crystal grains, small in diameter of inclusions and small in quantity, so that the surfacing layer is high in toughness and good in high-temperature stability. The experimental result shows that the hardness of the overlaying layer is more than or equal to 52HRc after the tempering at the temperature of 520-550 ℃.

For a further understanding of the present invention, the flux cored wire provided by the present invention is described in detail below with reference to specific embodiments. The scope of protection of the present application is not limited by the embodiments.