阅读说明：本技术 一种合金碎粒烧结体的激光焊接方法 (Laser welding method of alloy particle sintered body ) 是由 蒋武峰 于 2021-06-27 设计创作，主要内容包括：本发明涉及一种合金碎粒烧结体的激光焊接方法,涉及焊接的技术领域。本发明的合金碎粒烧结体的激光焊接方法,包括以下步骤：(1)提供表面形成有过渡层的合金碎粒烧结体；并且过渡层的原料组成为Fe:45-60wt.％,Mn:2-5wt.％,余量为铜和不可避免的杂质；(2)将过渡层与钢基体相对设置,并通过激光焊接形成复合体。本发明的激光焊接方法能够保证极高的焊接强度,并且焊缝外观平滑连续,无孔洞、凹陷等焊接缺陷；且未采用价格高昂的Co等金属材料,经济性,具有良好的实用前景。(The invention relates to a laser welding method of an alloy particle sintered body, and relates to the technical field of welding. The laser welding method of the alloy particle sintered body of the invention comprises the following steps: (1) providing an alloy particle sintered body with a transition layer formed on the surface; the transition layer comprises 45-60 wt% of Fe, 2-5 wt% of Mn and the balance of copper and inevitable impurities; (2) the transition layer is arranged opposite to the steel substrate, and a composite body is formed by laser welding. The laser welding method can ensure extremely high welding strength, and the appearance of a welding seam is smooth and continuous without welding defects such as holes, depressions and the like; and the high-price Co and other metal materials are not adopted, so that the method is economical and has good practical prospect.)

1. A laser welding method of an alloy particle sintered body is characterized by comprising the following steps:

(1) providing an alloy particle sintered body with a transition layer formed on the surface; the transition layer comprises 45-60 wt% of Fe, 2-5 wt% of Mn and the balance of copper and inevitable impurities;

(2) and arranging the transition layer opposite to the steel substrate, and forming a composite body by laser welding.

2. The laser welding method of an alloy granulated sintered body according to claim 1, characterized in that: the bending strength of the laser welding seam formed by laser welding is more than 2200 MPa.

3. The laser welding method of an alloy granulated sintered body according to claim 1, characterized in that: the thickness of the transition layer is 1.0-2.0 mm.

4. The laser welding method of an alloy granulated sintered body according to claim 1, characterized in that: the transition layer comprises 45-55 wt% of Fe, 2-4 wt% of Mn and the balance of copper and inevitable impurities.

5. The laser welding method of an alloy granulated sintered body according to claim 1, characterized in that: the content of C in the raw material composition of the transition layer is <0.10 wt.%.

6. The laser welding method of an alloy granulated sintered body according to claim 1, characterized in that: the laser welding process parameters are as follows: performing double-sided laser welding by using a laser, wherein the diameter of a laser spot is 0.3mm, the laser power is 700- & lt730W, and the welding speed is 10-16 mm/s; the protective gas is argon, the flow of the protective gas is 0.5L/min, the defocusing amount is 1.2-1.8mm, the laser beam deflects to one side of the substrate, the offset is 0.2-0.4mm, the laser incident angle is 12-14 degrees, the weld width is 1-1.3mm, and the penetration depth is 2-2.4 mm.

7. The laser welding method of an alloy granulated sintered body according to claim 1, characterized in that: the thickness of the alloy particle sintered body is larger than that of the steel substrate, for example, the thickness of the hard alloy particle cutting head is 1.2 to 2.0 times, preferably 1.3 to 1.6 times of that of the steel substrate.

8. The laser welding method of an alloy granulated sintered body according to claim 1, characterized in that: the steel matrix is 65 Mn.

9. A composite body, characterized by: a method for laser welding the alloy granulated sintered body according to any one of claims 1 to 8.

10. The composite of claim 9, wherein: the composite body is a cutting tool.

Technical Field

The invention relates to the technical field of welding, in particular to a laser welding method of an alloy particle sintered body.

Background

In the prior art, the alloy particle sintered body is generally welded to the base body by brazing, laser welding, or the like. However, the brazing process needs to integrally sinter and form the alloy particle material and the metal substrate, and the forming process is complex, so that the efficiency is not high; laser welding generally requires expensive Co, which limits the application of laser welding processes.

Disclosure of Invention

In order to solve the above technical problems in the prior art, an object of the present invention is to provide a laser welding method for an alloy particle sintered body.

A laser welding method of an alloy particle sintered body is characterized by comprising the following steps:

(1) providing an alloy particle sintered body with a transition layer formed on the surface; the transition layer comprises 45-60 wt% of Fe, 2-5 wt% of Mn and the balance of copper and inevitable impurities;

(2) and arranging the transition layer opposite to the steel substrate, and forming a composite body by laser welding.

Wherein the bending strength of the laser welding seam formed by laser welding is more than 2200 MPa.

Wherein the thickness of the transition layer is 1.0-2.0 mm.

Wherein, the transition layer comprises 45-55 wt% of Fe, 2-4 wt% of Mn and the balance of copper and inevitable impurities.

Wherein the content of C in the raw material composition of the transition layer is <0.10 wt.%.

Wherein the laser welding process parameters are as follows: performing double-sided laser welding by using a laser, wherein the diameter of a laser spot is 0.3mm, the laser power is 700- & lt730W, and the welding speed is 10-16 mm/s; the protective gas is argon, the flow of the protective gas is 0.5L/min, the defocusing amount is 1.2-1.8mm, the laser beam deflects to one side of the substrate, the offset is 0.2-0.4mm, the laser incident angle is 12-14 degrees, the weld width is 1-1.3mm, and the penetration depth is 2-2.4 mm.

Wherein the thickness of the alloy particle sintered body is larger than that of the steel matrix, for example, the thickness of the hard alloy particle cutting head is 1.2 to 2.0 times, preferably 1.3 to 1.6 times of that of the steel matrix.

Wherein the steel matrix is 65 Mn.

Wherein the alloy particle sintered body is formed by cold pressing cemented carbide particles and metal powder into a blank material, and the blank material is formed by hot pressing sintering.

The second aspect of the present invention also relates to a composite obtained by the above-described method for laser welding the alloy particle sintered body.

Wherein the composite body is a cutting tool.

Compared with the prior art, the laser welding method of the alloy particle sintered body has the following beneficial effects:

the laser welding method can ensure extremely high welding strength, and the appearance of a welding seam is smooth and continuous without welding defects such as holes, depressions and the like; and the high-price Co and other metal materials are not adopted, so that the method is economical and has good practical prospect.

Drawings

Fig. 1 is a schematic view showing the structure of a composite body formed by laser welding of an alloy fragment sintered body according to the present invention.

FIG. 2 is a photograph of an example of an application of the composite of FIG. 1.

Detailed Description

The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention. The invention is described in more detail in the following paragraphs by way of example with reference to the accompanying drawings. Advantages and features of the present invention will become apparent from the following description and from the claims. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

Fig. 1 shows a composite body formed by welding a steel substrate 10 and an alloy-grain sintered body 20 by laser welding of the present invention, and fig. 2 shows an example of a specific formation, i.e., an alloy-grain cutting tool.

The laser welding method of the alloy particle sintered body of the invention is characterized by comprising the following steps: (1) providing an alloy particle sintered body with a transition layer with the thickness of 1.0-2.0 mm formed on the surface; the transition layer is made of 45-60 wt.% of Fe, 2-5 wt.% of Mn and the balance of copper and inevitable impurities, more preferably 45-55 wt.% of Fe, 2-4 wt.% of Mn and the balance of copper and inevitable impurities, and the content of C in the transition layer is less than 0.10 wt.%; (2) and arranging the transition layer opposite to the steel substrate, and forming a composite body by laser welding. In the invention, the quality of a welding seam of laser welding is ensured by adding manganese, and when the addition of manganese is less than 2 wt.%, pores are easily generated, so that the compactness is insufficient; whereas if the manganese is added in an amount exceeding 5 wt.%, it may cause the formation of brittle phases, resulting in a decrease in strength; since the iron material generally contains carbon, the carbon content of the transition layer should be less than 0.10 wt.% in the material, which would otherwise result in a significant reduction in bending strength.

The bending strength of the laser welding seam formed by the laser welding method is more than 2200 MPa. Arranging a transition layer and a steel matrix oppositely, adjusting a light spot of a laser welding machine to a proper position of the transition layer and the steel matrix, starting the laser welding machine for welding, and welding an alloy particle sintered body and the steel matrix together at the moment of laser penetration, wherein the laser welding process parameters are as follows: performing double-sided laser welding by using a laser, wherein the diameter of a laser spot is 0.3mm, the laser power is 700- & lt730W, and the welding speed is 10-16 mm/s; the protective gas is argon, the flow of the protective gas is 0.5L/min, the defocusing amount is 1.2-1.8mm, the laser beam deflects to one side of the substrate, the offset is 0.2-0.4mm, the laser incident angle is 12-14 degrees, the weld width is 1-1.3mm, and the penetration depth is 2-2.4 mm.

In the present invention, the thickness of the alloy fragment sintered body may be greater than the thickness of the steel substrate, for example, the thickness of the cemented carbide fragment cutting head is 1.2 to 2.0 times, preferably 1.3 to 1.6 times the thickness of the steel substrate. The steel matrix is 65 Mn.

In the present invention, the alloy particle sintered body is formed by cold-pressing cemented carbide particles and metal powder into a blank, and the blank is formed by hot-press sintering. As a non-limiting application example, in the present invention, the alloy tip 2 is composed of the following raw materials by weight percentage: 15-35% of copper, 20-45% of iron, 3-8% of nickel, 3-9% of tin, 2-12% of zinc, 2-10% of manganese, 10-20% of tungsten carbide, 0.1-1% of liquid paraffin and 1-2.1% of hard alloy particles. In the copper-iron matrix, proper amounts of zinc, manganese and tin are prepared for sintering together, so that densification sintering can be guaranteed under the condition of hot-pressing sintering, infiltration and bonding of hard alloy particles can be guaranteed, and when the alloy particle sintered body is used as a cutting tool, the collapse and ejection of the hard alloy particles can be greatly reduced, and the safety of personnel is guaranteed.

In the present invention, the composition of the cemented carbide granules in the alloy insert 2 is LG8, and the particle size of the commercially available LG8 (composition of 92 wt% WC +6 wt% Co +2 wt% Ni) is 250 to 425 μm.

Example 1

The laser welding method of the present embodiment is as follows:

1. preparing a polished and flattened 65Mn steel disc-shaped substrate;

2. preparing an alloy particle sintered body: 2.3kg of copper powder, 3.55kg of iron, 0.64kg of nickel, 0.84kg of zinc, 0.72kg of tin, 0.6kg of manganese and 1.1kg of tungsten carbide are taken, put into a mixing barrel and mixed for 30 minutes, 0.1kg of liquid paraffin and 0.15kg of hard alloy particles are added and mixed for 3 hours, and then the powder is poured into a mold for cold pressing and molding; the transition layer is made of Fe50 wt%, Mn4 wt% and Cu in balance, and the C content in the raw materials<0.10 wt.%, and cold press molding after the transition layer raw materials are uniformly mixed; arranging a transition layer with the thickness of 1.5mm on the inner side of the alloy particle sintered body after cold press molding, connecting the alloy particle sintered body and the transition layer together through hot press sintering, and grinding the alloy particle sintered body and the transition layer through a grinding wheel abrasive belt to prepare the alloy particle sintered body with the transition layer, wherein the sintering temperature of the hot press sintering is 1000 ℃, and the pressure is 310kg/cm²Keeping the temperature for 3 minutes;

3. laser welding: placing the alloy particle sintered body at a corresponding position around a 65Mn steel disc-shaped substrate, adjusting a light spot of a laser welding machine to a proper position of the alloy particle sintered body and the substrate, and starting a laser welding machine for welding to enable the alloy particle sintered body and the 65Mn steel disc-shaped substrate to be welded together at the moment when laser penetrates; the welding process parameters are as follows: performing double-sided laser welding by using a laser, wherein the diameter of a laser spot is 0.3mm, the laser power is 710W, and the welding speed is 12 mm/s; the protective gas is argon, the flow of the protective gas is 0.5L/min, the defocusing amount is 1.3mm, the laser beam deflects to one side of the substrate, the offset is 0.2mm, the laser incident angle is 12 degrees, the width of a welding seam is 1.1mm, and the penetration depth is 2 mm.

Through detection, the bending strength of the laser welding seam is 2245 MPa.

Example 2

The laser welding method of the present embodiment is as follows:

1. preparing a polished and flattened 65Mn steel disc-shaped substrate;

2. preparing an alloy particle sintered body: 2.21kg of copper powder, 3.69kg of iron, 0.59kg of nickel, 0.86kg of zinc, 0.7kg of tin, 0.59kg of manganese and 1.11kg of tungsten carbide are taken, put into a mixing barrel and mixed for 30 minutes, 0.09kg of liquid paraffin and 0.16kg of hard alloy particles are added, mixed for 3 hours, and then the powder is poured into a mold for cold pressing and molding; the transition layer is made of raw materials of Fe50 wt%, Mn3 wt% and the balance of Cu, the content of C in the raw materials is less than 0.10 wt%, and the raw materials of the transition layer are uniformly mixed and then subjected to cold press molding;

arranging a transition layer with the thickness of 1.5mm on the inner side of the alloy particle sintered body after cold press molding, connecting the alloy particle sintered body and the transition layer together through hot press sintering, and grinding the alloy particle sintered body and the transition layer through a grinding wheel abrasive belt to prepare the alloy particle sintered body with the transition layer, wherein the sintering temperature of the hot press sintering is 1000 ℃, the pressure is 310kg/cm2, and the heat preservation time is 3 minutes;

3. laser welding: placing the alloy particle sintered body at a corresponding position around a 65Mn steel disc-shaped substrate, adjusting a light spot of a laser welding machine to a proper position of the alloy particle sintered body and the substrate, and starting a laser welding machine for welding to enable the alloy particle sintered body and the 65Mn steel disc-shaped substrate to be welded together at the moment when laser penetrates; the welding process parameters are as follows: performing double-sided laser welding by using a laser, wherein the diameter of a laser spot is 0.3mm, the laser power is 720W, and the welding speed is 6 mm/s; the protective gas is argon, the flow of the protective gas is 0.5L/min, the defocusing amount is 1.8mm, the laser beam deflects to one side of the substrate, the offset is 0.4mm, the laser incident angle is 14 degrees, the width of a welding seam is 1mm, and the penetration depth is 2.4 mm.

Through detection, the bending strength of the laser welding seam is 2240 MPa.

Comparative example 1

The laser welding method of the alloy pellet sintered body of this comparative example was as follows:

1. preparing a polished and flattened 65Mn steel disc-shaped substrate;

2. preparing an alloy particle sintered body: 2.3kg of copper powder, 3.55kg of iron, 0.64kg of nickel, 0.84kg of zinc, 0.72kg of tin, 0.6kg of manganese and 1.1kg of tungsten carbide are taken, put into a mixing barrel and mixed for 30 minutes, 0.1kg of liquid paraffin and 0.15kg of hard alloy particles are added and mixed for 3 hours, and then the powder is poured into a mold for cold pressing and molding; the transition layer is made of raw materials of Fe50 wt%, Mn4 wt% and the balance of Cu, wherein the raw material Fe is low-carbon steel with the carbon content of 0.25 wt%, and the raw materials of the transition layer are uniformly mixed and then subjected to cold press molding; uniformly mixing the transition layer raw materials, and then carrying out cold press molding; arranging a transition layer with the thickness of 1.5mm on the inner side of the alloy particle sintered body after cold press molding, connecting the alloy particle sintered body and the transition layer together through hot press sintering, and grinding the alloy particle sintered body and the transition layer through a grinding wheel abrasive belt to prepare the alloy particle sintered body with the transition layer, wherein the sintering temperature of the hot press sintering is 1000 ℃, and the pressure is 310kg/cm²Keeping the temperature for 3 minutes;

3. laser welding: placing the alloy particle sintered body at a corresponding position around a 65Mn steel disc-shaped substrate, adjusting a light spot of a laser welding machine to a proper position of the alloy particle sintered body and the substrate, and starting a laser welding machine for welding to enable the alloy particle sintered body and the 65Mn steel disc-shaped substrate to be welded together at the moment when laser penetrates; the welding process parameters are as follows: performing double-sided laser welding by using a laser, wherein the diameter of a laser spot is 0.3mm, the laser power is 710W, and the welding speed is 12 mm/s; the protective gas is argon, the flow of the protective gas is 0.5L/min, the defocusing amount is 1.3mm, the laser beam deflects to one side of the substrate, the offset is 0.2mm, the laser incident angle is 12 degrees, the width of a welding seam is 1.1mm, and the penetration depth is 2 mm.

The bending strength of the laser welding seam is 960MPa through detection.

Comparative example 2

The laser welding method of this comparative example is as follows:

1. preparing a polished and flattened 65Mn steel disc-shaped substrate;

2. preparing an alloy particle sintered body: 2.21kg of copper powder, 3.69kg of iron, 0.59kg of nickel, 0.86kg of zinc, 0.7kg of tin, 0.59kg of manganese and 1.11kg of tungsten carbide are taken, put into a mixing barrel and mixed for 30 minutes, 0.09kg of liquid paraffin and 0.16kg of hard alloy particles are added, mixed for 3 hours, and then the powder is poured into a mold for cold pressing and molding; the transition layer raw materials comprise Fe50 wt%, the balance of Cu, the content of C in the raw materials is less than 0.10 wt%, and the transition layer raw materials are uniformly mixed and then subjected to cold press molding; uniformly mixing the transition layer raw materials and then performing cold press molding;

arranging a transition layer with the thickness of 1.5mm on the inner side of the alloy particle sintered body after cold press molding, connecting the alloy particle sintered body and the transition layer together through hot press sintering, and grinding the alloy particle sintered body and the transition layer through a grinding wheel abrasive belt to prepare the alloy particle sintered body with the transition layer, wherein the sintering temperature of the hot press sintering is 1000 ℃, the pressure is 310kg/cm2, and the heat preservation time is 3 minutes;

3. laser welding: placing the alloy particle sintered body at a corresponding position around a 65Mn steel disc-shaped substrate, adjusting a light spot of a laser welding machine to a proper position of the alloy particle sintered body and the substrate, and starting a laser welding machine for welding to enable the alloy particle sintered body and the 65Mn steel disc-shaped substrate to be welded together at the moment when laser penetrates; the welding process parameters are as follows: performing double-sided laser welding by using a laser, wherein the diameter of a laser spot is 0.3mm, the laser power is 720W, and the welding speed is 6 mm/s; the protective gas is argon, the flow of the protective gas is 0.5L/min, the defocusing amount is 1.8mm, the laser beam deflects to one side of the substrate, the offset is 0.4mm, the laser incident angle is 14 degrees, the width of a welding seam is 1mm, and the penetration depth is 2.4 mm.

The bending strength of the laser welding seam is 1050MPa through detection.

It is obvious to those skilled in the art that the specific embodiments are only exemplary descriptions of the present invention, and it is obvious that the specific implementation of the present invention is not limited by the above-mentioned manner, and various insubstantial modifications made by the method concept and technical scheme of the present invention are within the protection scope of the present invention.