CN108145340B

CN108145340B - High-temperature-resistant abrasive-particle-wear-resistant welding wire for distribution chute and preparation method

Info

Publication number: CN108145340B
Application number: CN201711404976.5A
Authority: CN
Inventors: 胡东润
Original assignee: Zhuhai Hongde Surface Technology Co ltd
Current assignee: Zhuhai Hongde Surface Technology Co ltd
Priority date: 2017-12-22
Filing date: 2017-12-22
Publication date: 2020-09-29
Anticipated expiration: 2037-12-22
Also published as: CN108145340A

Abstract

The invention provides a high-temperature-resistant wear-resistant granular wear-resistant welding wire for a distribution chute, which comprises the following components in percentage by mass: 16-30% of chromium metal powder, 5-15% of ferromolybdenum, 0.8-5% of tungsten carbide, 3-12% of niobium powder, 0.8-7% of ferroboron, 0.3-5% of titanium dioxide, 1-5% of silicon dioxide, 0.9-5% of manganese metal, 0.3-6% of rare earth additive, 0.02-0.1% of copper powder and the balance of iron powder. The welding wire provided by the invention has the advantages of easily obtained raw materials, simple preparation process, higher hardness of a welded sample block, good wear resistance and low production cost, and can be widely applied to a medium-low stress abrasive wear environment below 800 ℃, particularly a material distribution chute of a smelting plant and can replace imported materials.

Description

High-temperature-resistant abrasive-particle-wear-resistant welding wire for distribution chute and preparation method

Technical Field

The invention belongs to the field of welding materials, and particularly relates to a high-temperature-resistant abrasive wear-resistant self-protection welding wire for a distribution chute and a preparation method thereof.

Background

The material distributing chute is one key part of bell-less distributor for iron smelting blast furnace and is the last passage for smelting material to flow into the blast furnace body for homogeneous spreading of the blast furnace material. The distribution chute surfaces are subjected to severe abrasive wear and must therefore be manufactured from high temperature, wear resistant materials. If the chute is integrally made of high-wear-resistant materials, the manufacturing cost of the chute is very high, so that the adoption of the wear-resistant lining plate on the surface of the chute is an economic and scientific method, and the wear resistance of the lining plate is improved in two ways. Firstly, when the lining plate is manufactured, the integral wear-resistant alloy is adopted for casting, and secondly, the composite wear-resistant surfacing method is adopted for manufacturing. Although the lining plate cast by the integral wear-resistant alloy has better wear resistance, the lining plate has more problems, and the composite wear-resistant surfacing method can ensure that the surface of a workpiece has good wear resistance, ensure that a roller body has good comprehensive mechanical property and does not have the risk of cracking or breaking, thereby providing higher requirements for welding wires.

The self-shielded welding wire is a welding wire which does not need additional gas or flux protection and only depends on the chemical reaction of the alloy elements of the welding wire at high temperature so as to prevent oxygen, hydrogen and other gases in the air from entering and supplement alloy components. The surfacing welding wire is generally used for welding a layer of special alloy surface at any part of a surfacing workpiece, and aims to improve the wear resistance, corrosion resistance, heat resistance and other properties of a working surface so as to reduce the cost, improve the comprehensive performance and prolong the service life.

Currently, hard-face surfacing materials are mainly divided into three directions: firstly, welding wires, secondly, manual welding electrodes and strip welding strips, wherein the welding wire surfacing materials are divided into submerged arc welding wires and self-shielded flux-cored welding wires, and the self-shielded flux-cored welding wires are efficient, material-saving and low-cost flux-cored welding wires which do not need additional gas or flux protection, so that the self-shielded flux-cored welding wires are efficient, and because the welding wires are easy to realize automation and the welding seams do not have slag, the problem of slag removal is solved, and continuous welding can be realized; the material is saved, and about 25 percent of deposited metal can be saved by the flux-cored wire; as for low cost, because such wires do not require gas or flux shielding, production costs can be reduced. The flux-cored wire can be used for welding carbon steel, low-alloy high-tension steel, high-strength quenched and tempered steel, stainless steel, hard-surface wear-resistant steel and the like. The flux-cored wire has the following advantages: the welding flux has strong adaptability to the welding of various steel products, is extremely convenient and easy to adjust the components and the proportion of the welding flux, and can provide the required chemical components of the welding seam; the process performance is good, the weld joint is attractive in appearance, the gas-slag combined protection is adopted, good forming is obtained, the arc stabilizer is added to stabilize the electric arc, and the molten drop transition is uniform; the deposition speed is high, the production efficiency is high, the current density of the flux-cored welding wire is high under the same welding current, the melting speed is high, the deposition rate is about 85-90 percent, and the production rate is about 3-5 times higher than that of shielded metal arc welding; full position welding can be performed with a relatively high welding current, however, flux cored wires also have their drawbacks, mainly including: the welding wire manufacturing process is complex; during welding, the wire feeding is more difficult than that of a solid welding wire; the surface of the welding wire is easy to rust, and the powder is easy to absorb moisture, so that the requirement on the storage and management of the flux-cored wire is stricter.

CN102233491A discloses a self-protection flux-cored wire, which comprises a steel strip and a welding agent, wherein the welding agent is filled in the steel strip, the welding agent comprises 1-3% of aluminum powder, 3-5% of rare earth silicon, 1-3% of ferrovanadium, 50-65% of high-carbon ferrochrome, 10-15% of niobium powder, 10-20% of ferromolybdenum and 2-5% of tungsten carbide in percentage by weight, and the filling rate of the welding agent in the steel strip is 40-50%. By adjusting the proportion of the alloy powder, the invention has higher hardness under different temperature conditions, and has higher hardness under both room temperature conditions and high temperature (up to 600 ℃), thereby enlarging the use occasions of hard-surface materials, reducing the limitation of the use temperature of workpieces on the materials, and reducing the complicated processes of needing various welding materials during welding.

When the surfacing material on the market is used in a room temperature environment, the hardness value of the surfacing surface is difficult to meet the requirement, and when the surfacing material is used in a high temperature environment, the hardness is reduced due to the fact that the material is easy to creep at high temperature, and the higher hardness value is difficult to achieve. Therefore, welding wires of domestic enterprises are generally imported from abroad, so that the construction period process is delayed, and the production cost is increased.

Disclosure of Invention

In order to solve the problems in the prior art, the invention aims to provide a high-temperature-resistant wear-resistant welding wire for a distribution chute.

The invention also aims to provide a preparation method of the welding wire.

In order to achieve the purpose, the invention adopts the following technical scheme:

the high-temperature-resistant abrasive-particle-wear-resistant welding wire for the distribution chute comprises a flux core and a sheath, wherein the flux core comprises the following components in percentage by mass:

16-30% of metal chromium powder,

5 to 15 percent of ferromolybdenum,

0.8 to 5 percent of tungsten carbide,

3 to 12 percent of niobium powder,

0.8 to 7 percent of ferroboron,

0.3 to 5 percent of titanium dioxide,

1 to 5 percent of silicon dioxide,

0.9 to 5 percent of metal manganese,

0.3 to 6 percent of rare earth additive,

0.02 to 0.1 percent of copper powder,

the balance being iron powder.

Preferably, the chromium content of the metal chromium powder is more than 95 percent.

Preferably, the ferromolybdenum contains 70% of molybdenum.

Preferably, the tungsten carbide contains more than 95% of tungsten.

Preferably, the purity of the niobium powder is more than 98%.

Preferably, the ferroboron contains 21% of boron.

Preferably, the titanium dioxide is greater than 98% pure.

Preferably, the silica has a purity of greater than 99.7%.

Preferably, the purity of the manganese metal is more than 99.7%.

Preferably, the rare earth additive is CeO₂And La₂O₃A mixture of (a).

Preferably, CeO is present in said mixture₂And La₂O₃The weight ratio of (2-5) to (1).

A preparation method of a high-temperature-resistant abrasive wear-resistant welding wire for a distribution chute comprises the following steps:

(1) mixing and stirring the raw material powder uniformly according to a ratio, and then putting the mixture into a furnace to dry for 2 hours at 180-200 ℃ to obtain medicine core powder;

(2) rolling a low-carbon steel strip into a U-shaped groove, filling the flux-cored powder obtained in the step (1) into the U-shaped groove, rolling the groove by a forming machine, closing and drawing to obtain a flux-cored wire;

(3) and (3) finally, straightening the flux-cored wire prepared in the step (2) by using a wire drawing machine.

Preferably, the filling rate of the medicine core powder in the step (2) is 49-52%.

Preferably, the drawing standard in the step (2) is that the diameter of the flux-cored wire reaches 2.8-3.2 mm.

The invention has the advantages of

1. The raw materials of the welding wire formula provided by the invention are easy to obtain, the preparation process is simple, and the production cost is low;

2. the welding wire prepared by the invention has the advantages that the microstructure of the obtained welding sample block is pure, slag and air holes are avoided, the hardness is higher, and the wear resistance is good;

3. the welding wire provided by the invention can be widely applied to the medium-low stress abrasive wear environment below 800 ℃, especially to a distribution chute of a smelting plant, and can replace imported materials.

Drawings

1. FIG. 1 is a Rockwell hardness microhardness test chart of sample C;

2. FIG. 2 is a metallographic structure of sample C;

3. FIG. 3 is a microstructure diagram of sample C.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the accompanying drawings, but the present invention is not limited to these embodiments.

Example 1

The embodiment provides a preparation method of a high-temperature-resistant wear-resistant particle wear-resistant welding wire for a distribution chute, which comprises the following steps:

(1) mixing and stirring the raw materials uniformly according to a ratio, and then putting the mixture into a furnace to dry for 2 hours at 180-200 ℃ to obtain medicine core powder;

(2) placing the low-carbon steel strip on a strip placing machine of a welding wire forming machine, rolling the low-carbon steel strip into a U-shaped groove through the forming machine, filling the flux-cored powder obtained in the step (1) into the U-shaped groove with the filling rate of 50%, rolling the groove through the forming machine, closing and drawing to obtain the flux-cored welding wire;

(3) and (3) straightening the flux-cored wire prepared in the step (2) by using a wire drawing machine until the diameter reaches 2.8mm, taking a rear disc as a circular disc, and sealing and packaging to obtain a finished product.

Example 2

(3) and (3) straightening the flux-cored wire prepared in the step (2) by using a wire drawing machine until the diameter reaches 3.2mm, taking a rear disc as a circular disc, and sealing and packaging to obtain a finished product.

Example 3

Three welding wires A to C were prepared by the method provided in example 1, and three welding wires D to F were prepared by the method provided in example 2, with the specific composition ratios shown in Table 1.

TABLE 1 welding wire proportioning particulars

Example 4

The present example compares the welding performance of different welding wires, and the results are shown in table 2.

TABLE 2 weld Process Performance comparison of welding wires

Sample (I)	Arc stability	Weld seam formation	Crack(s)
				A	Good arc stability and easy arc striking	No slag after welding and good forming	Surface crack-free
B	Good arc stability and easy arc striking	No slag after welding and good forming	Surface crack-free
				C	The arc stability is good, and the arc is easy to strike	No slag after welding and good forming	Surface crack-free
D	Good arc stability and easy arc striking	No slag after welding and good forming	Surface crack-free
				E	Good arc stability and easy arc striking	No slag after welding and good forming	Surface crack-free
F	Good arc stability and easy arc striking	No slag after welding and good forming	Having micro cracks on the surface

Example 5

The high-temperature abrasion of the lining plate of the distribution chute can reduce the hardness of the lining plate, greatly influence the abrasion resistance of the lining plate and accelerate the failure of the lining plate under the continuous impact of materials. In order to ensure the wear resistance of the material at high temperature, 16Mn steel plates are selected as base materials in the implementation, and welding wires A-F are used for carrying out welding process performance and related tests. Firstly, performing high-temperature heat treatment on corresponding surfacing test sample blocks obtained by using welding wires A-F at 750 ℃, 800 ℃ and 850 ℃, keeping the temperature for 3 hours, slowly cooling to room temperature, measuring the hardness of the sample blocks by using a microRockwell hardness tester, wherein a Rockwell hardness microhardness test chart of a sample C is shown in a figure 1, comparing the sample blocks which are not subjected to heat treatment, randomly selecting 5 points for testing the hardness of each sample block, and then averaging, wherein the result is shown in a table 3, as can be seen from the table 3, when the temperature is not more than 800 ℃, the influence of the high-temperature heat treatment on the hardness of the surfacing test sample blocks is small, and when the temperature reaches 850 ℃, the hardness of the sample blocks using the welding wires A-F is obviously reduced. In addition, the sample block is also subjected to an abrasive wear test under the same conditions, the test time is 15min, the obtained results are shown in table 4, it can be seen from table 4 that when the temperature does not exceed 800 ℃, the influence of high-temperature heat treatment on wear resistance of the wear-resistant particles of the surfacing test sample block is small, when the temperature reaches 850 ℃, the abrasive wear loss of the rest sample blocks is obviously increased in the sample blocks using the a-F welding wires except the sample block using the C welding wire, the microstructure of the sample block using the C welding wire is also observed in the embodiment, fig. 2 is a metallographic structure diagram of the sample block using the C welding wire, and fig. 3 is a microstructure diagram of the sample block using the C welding wire.

TABLE 3 Rockwell hardness test results

TABLE 4 abrasion test results for the pieces

Claims

1. The high-temperature-resistant abrasive-particle-wear-resistant welding wire for the distribution chute comprises a flux core and a sheath, and is characterized in that the flux core comprises the following components in percentage by mass:

16 percent of metal chromium powder,

5 percent of ferromolybdenum,

0.8 percent of tungsten carbide,

3 percent of niobium powder,

0.8 percent of ferroboron,

0.3 percent of titanium dioxide,

1 percent of silicon dioxide,

0.9 percent of metal manganese,

0.3 percent of rare earth additive,

0.02 percent of copper powder,

the balance of iron powder;

the rare earth additive is CeO₂And La₂O₃A mixture of (a);

CeO in the mixture₂And La₂O₃In a weight ratio of 5: 1.

2. The high temperature resistant, abrasive wear resistant welding wire of claim 1 wherein said chromium metal powder comprises greater than 95% chromium.

3. The high temperature, abrasive and wear resistant welding wire of claim 1, wherein the ferromolybdenum contains 70% molybdenum.

4. The high temperature, abrasive and wear resistant welding wire of claim 1, wherein the tungsten carbide comprises greater than 95% tungsten.

5. The high temperature and abrasive wear resistant welding wire of claim 1, wherein the ferroboron has a boron content of 21%.

6. The preparation method of the high-temperature-resistant wear-resistant particle wear-resistant welding wire for the distribution chute as claimed in any one of claims 1 to 5, characterized by comprising the following steps:

7. The method for preparing the high-temperature-resistant and wear-resistant welding wire according to claim 6, wherein the filling rate of the flux-cored powder in the step (2) is 49-52%.

8. The method for preparing the high-temperature-resistant and wear-resistant welding wire as claimed in claim 6, wherein the drawing standard in the step (2) is that the diameter of the flux-cored welding wire reaches 2.8-3.2 mm.