LU600595B1

LU600595B1 - Laser cladding material of wc reinforced ni60aa and preparation method thereof

Info

Publication number: LU600595B1
Application number: LU600595A
Authority: LU
Inventors: Gaosong Li
Original assignee: Univ Huanghuai
Priority date: 2025-03-17
Filing date: 2025-03-17
Publication date: 2025-09-17

Abstract

The invention discloses a laser cladding material of WC reinforced Ni60AA and a preparation method thereof, belonging to the technical field of laser cladding. The laser cladding material of WC reinforced Ni60AA consists of WC particles and Ni60AA powder, and the mass ratio of the WC particles to the Ni60AA powder is (1-2): (8-9). The laser cladding material of WC reinforced Ni60AA can significantly improve the wear resistance and hardness of the cladding layer. The addition of WC particles also helps to refine the grain size, reduce the occurrence of cracks in the cladding process, and improve the mechanical properties of the cladding layer. In a word, the laser cladding material of the invention reduces the porosity and crack rate in the laser cladding process, and effectively solves the problems of uneven microstructure and properties and uncertain cladding material system.

Description

DESCRIPTION 10000008

LASER CLADDING MATERIAL OF WC REINFORCED NI60AA AND PREPARATION

METHOD THEREOF

TECHNICAL FIELD

The invention belongs to the technical field of laser cladding, in particular to a laser cladding material of WC reinforced NiIGOAA and a preparation method thereof.

BACKGROUND

As an advanced modification technology, laser cladding technology overcomes the shortcomings of traditional coatings (electroplating, thermal spraying and surfacing), such as large dilution rate, large deformation, large heat affected zone, difficult machining of holes and grooves, thin coating and single function, etc., and realizes metallurgical bonding between cladding layer and substrate, promotes crystal refinement, inhibits impurity precipitation, and improves hardness and wear resistance of cladding layer. At the same time, it provides a special processing environment for the cladding layer (instantaneous melting and solidification of alloy powder and matrix), and prepares a high- entropy alloy coating with high hardness, high wear resistance and certain toughness, which expands the application range of metals.

However, when laser cladding technology involves ceramic reinforced phase, cracks and bubbles are easy to appear in the cladding layer, which greatly limits the application range of laser cladding ceramic reinforced phase. There are differences in elastic modulus, thermal expansion coefficient, thermal conductivity and wettability between matrix and alloy powder, so thermal stress occurs in the process of laser cladding, and cracks will appear in the cladding layer when the thermal stress is greater than the crack resistance strength of the cladding layer.

Therefore, it is necessary to provide a laser cladding material and its preparation method to solve the problem of cracks easily occurring in the laser cladding process.

SUMMARY

In order to solve the above technical problems, the invention provides a laser cladding material of WC reinforced NiIGOAA and a preparation method thereof.

In order to achieve the above purpose, the invention provides a laser cladding material of WC reinforced NiGOAA, the raw materials are composed of WC particles and

Ni60AA powder, and the mass ratio of the WC particles to the NiGOAA powder is (1-2): (8-9).

For example, the laser cladding material of WC reinforced Ni6OAA of the present invention consists of WC particles and NiGOAA powder, and the mass ratio of the WC particles to the NiGOAA powder is 1: 9.

Another example is the laser cladding material of WC reinforced NiGOAA of the present invention. The raw materials are composed of WC particles and NiGOAA powder, and the mass ratio of the WC particles to the Ni6OA laser cladding material powder is 2: 8.

The laser cladding material of the present invention is composed of WC particles and

Ni60AA powder, and the WC particles are used as the reinforcing phase, so that the wear resistance of the cladding layer is significantly improved due to its high hardness and wear resistance. In the process of laser cladding, the combination between WC particles and substrate plays a key role, which improves the hardness of cladding layer and reduces the probability of cracks in cladding layer.

Further, the particle size of the WC particles is 400 -500 meshes, and the particle size of the NIGOAA powder is 100-300 meshes.

Further, the NiGOAA powder comprises the following components in percentage by mass: 0.4-0.9% of C, 13-16% of Cr, 3.0-4.6% of Si, 2.4-3.8% of B, 6-8% of Fe and the balance of Ni and inevitable impurities.

The invention also provides a preparation method of the laser cladding material of

WC reinforced NiGOAA, which comprises the following steps: accurately weighing WC particles and NiGOAA powder according to the mass ratio, uniformly mixing, ball milling and drying to obtain the laser cladding material of WC reinforced Ni60AA.

Further, in the ball milling, anhydrous ethanol is used as the ball milling medium, the grinding balls are zirconia balls, and the ball-to-material ratio is 3: 1. Ball-to-material ratio refers to the ratio of the mass of grinding balls and materials in a ball mill, which reflects the amount of materials stored in the mill under a certain ball loading.

Ball-to-material ratio is an important technological parameter that affects the outpyt 500595 and grinding efficiency of ball mill. Reasonable ball-to-material ratio can improve grinding efficiency, reduce energy consumption and improve grinding quality. If the ball-to-material ratio is too small, there will be too much material in the mill, which will easily produce buffering effect and reduce the grinding efficiency. However, if the ball-to-material ratio is too large, it will increase the useless work loss between grinding balls, reduce the grinding efficiency and increase the metal consumption.

Further, the rotation speed of the ball milling is 300-350 r/min, the ball milling time is 1-2 h, the rotation speed of the ball milling is 300 r/min, and the ball milling time is 1 hour.

Further, the drying temperature is 70-80°C, and the drying time is 2-3 h, preferably 75°C and 2 h.

Compared with the prior art, the invention has the following advantages and technical effects.

The laser cladding material of the invention consists of WC particles and NiGOAA powder, and the WC particles significantly improve the wear resistance of the cladding layer because of their high hardness and wear resistance. In the process of laser cladding, the combination between WC particles and substrate plays a key role, which improves the hardness of cladding layer. The addition of WC particles also helps to refine the grain size, reduce the occurrence of cracks in the cladding process, and improve the mechanical properties of the cladding layer. In a word, the laser cladding material of the invention reduces the porosity and crack rate in the laser cladding process, and effectively solves the problems of uneven microstructure and properties and uncertain cladding material system.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings, which constitute a part of the invention, are used to provide a further understanding of the invention, and the illustrative embodiments of the invention and their descriptions are used to explain the invention, and do not constitute an undue limitation of the invention. In the attached drawings:

Fig. 1 shows the change of microhardness from top to bottom of cladding layer in

Embodiment 2.

DESCRIPTION OF THE INVENTION LU600595

A number of exemplary embodiments of the present invention will now be described in detail, and this detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention.

It should be understood that the terminology described in the present invention is only for describing specific embodiments and is not used to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper limit and the lower limit of the range is also specifically disclosed. The intermediate value within any stated value or stated range and every smaller range between any other stated value or intermediate value within the stated range are also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

Unless otherwise specified, 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 relates. Although the present invention only describes the preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe methods and/or materials related to the documents. In case of conflict with any incorporated document, the contents of this specification shall prevail.

It is obvious to those skilled in the art that many improvements and changes can be made to the specific embodiments of the present invention without departing from the scope or spirit of the present invention. Other embodiments will be apparent to the skilled person from the description of the invention. The description and example of that present invention are exemplary only.

The terms "comprising", "including", "having" and "containing" used in this article are all open terms, which means including but not limited to.

Unless otherwise specified, the room temperature in the present invention is 25+2°C.

All the raw materials used in the embodiment of the invention are obtained by commercial purchase.

In the following embodiment of the invention, a 6-axis KUKA robot arm KR30 is used 600595 to drive the PERCITECYC52 cladding head for laser cladding, the laser is provided by

IPG fiber laser YLR-3000, and the powder is provided by FHPF-10 synchronous powder feeder. During laser cladding, the spot diameter is 2.50 mm, the powder feeding pressure (N2) is 0.3 MPa, the carrier gas flow rate is 600 L'h*, the protective pressure (N2) is 0.1

MPa, the laser wavelength is 1.08 um, the laser power is 700 W, the scanning speed is 2 mm/s, the powder feeding rate is 6 g/min, and the scanning mode is lap scanning, and the lap rate is 40%, and a 1 mm cladding layer is obtained. Cri2MoV cold die steel with matrix length, width and height of 10 mm, 7 mm and 6 mm respectively. The metallographic structure was observed by MR5000 inverted metallographic microscope.

The microhardness of the cladding layer was measured by HV-1000 microhardness tester. The applied load was 100 g, the duration was 10 s, and the test interval was 0.1 mm (calculated from the junction O of the cladding layer and the substrate). Before cladding, the substrate is polished with sandpaper, and then the oil stain on the surface of the substrate is removed with alcohol and acetone respectively.

In the following embodiments of the invention, WC particles were purchased from

Zibo Xinrunging Chemical Co., Ltd.; Ni6OAA powder consists of the following components in percentage by mass: 0.4-0.9% C, 13-16% Cr, 3.0-4.6% Si, 2.4-3.8% B, 6-8% Fe and the balance Ni and inevitable impurities.

It should be pointed out that what is not described in detail in this invention is a conventional operation method in this field, and it is not the focus of this invention.

The technical scheme of the present invention will be further explained by examples.

Embodiment 1

This embodiment provides a laser cladding material of WC reinforced Ni6OAA. The raw materials are composed of WC particles (450 mesh) and Ni60OAA powder (200 mesh), and the mass ratio of WC particles to Ni6OAA powder is 2:8.

The preparation method of the above-mentioned laser cladding material of WC reinforced NiGOAA comprises the following steps: accurately weighing WC particles and

NISOAA powder according to the mass ratio, uniformly mixing them, putting them into a planetary ball mill, using anhydrous ethanol as a ball milling medium and zirconia balls as grinding balls, ball-to-material ratio is 3: 1, ball milling is carried out at a rotating speed of 320 r/min for 1.5 h, and then drying at 75°C for 2 h to obtain the laser cladding material of WC reinforced NiGOAA.

Laser cladding test: the substrate (Cri2MoV cold die steel) is polished With 600595 sandpaper, and then the oil stain on the surface of the substrate is removed with alcohol and acetone respectively to obtain the cleaned substrate. The 6-axis KUKA robot arm

KR30 is used to drive the PERCITECYC52 cladding head for laser cladding. The laser cladding material is the laser cladding material of WC reinforced Ni6OAA prepared in this embodiment. The laser is provided by IPG fiber laser YLR-3000 and the powder is provided by FHPF. During laser cladding, the spot diameter is 2.50 mm, the powder feeding pressure (N2) is 0.3 MPa, the carrier gas flow rate is 600 L'h*, the protective pressure (Na) is 0.1 MPa, the laser wavelength is 1.08 um, the laser power is 700 W, the scanning speed is 2 mm/s, the powder feeding rate is 6 g/min, and the scanning mode is lap scanning, and the lap rate is 40%, and a 1 mm cladding layer is obtained. Cri2MoV cold die steel with matrix length, width and height of 10 mm, 7 mm and 6 mm respectively.

The metallographic structure was observed by MR5000 inverted metallographic microscope. The microhardness of the cladding layer was measured by HV-1000 microhardness tester. The applied load was 100 g, the duration was 10 s, and the test interval was 0.1 mm (calculated from the junction O of the cladding layer and the substrate).

It can be seen from the micro-morphology of the cladding layer in this embodiment that the relative content of WC particles in the laser cladding material in this embodiment is high, which improves the microhardness of the cladding layer and reduces the thickness of the bonding cladding layer. The reduction of the thickness of the bonding cladding layer weakens the ability of the cladding layer to resist thermal stress, which makes the thinner cladding layer crack when the thinner and thicker cladding layers are subjected to the same thermal stress, thus reducing the probability of cracks in the cladding layer.

Embodiment 2

This embodiment provides a laser cladding material of WC reinforced Ni6OAA. The raw materials are composed of WC particles (500 meshes) and Ni6OAA powder (300 meshes), and the mass ratio of WC particles to Ni6OAA powder is 1: 9;

The preparation method of the above-mentioned laser cladding material of WC 600595 reinforced NiGOAA comprises the following steps: accurately weighing WC particles and

NISOAA powder according to the mass ratio, uniformly mixing them, putting them into a planetary ball mill, taking anhydrous ethanol as the ball milling medium and zirconia balls as the grinding balls, ball-to-material ratio is 3: 1, ball milling is carried out at the speed of 300 r/min for 2 h, and then drying at 80°C for 2 h to obtain the laser cladding material of

WC reinforced Ni6OAA.

Laser cladding test: the substrate (Cri2MoV cold die steel) is polished with sandpaper, and then the oil stain on the surface of the substrate is removed with alcohol and acetone respectively to obtain the cleaned substrate. The 6-axis KUKA robot arm

The change of microhardness from the top to the bottom of the cladding layer in this embodiment is shown in Fig. 1. As can be seen from Fig. 1, the microhardness of the cladding layer has undergone two alternating changes of peaks and valleys. The microhardness of the first peak is greater than that of the valleys and metallurgical bonding areas, and the lowest microhardness is also 2.8 times that of the matrix. The above phenomena can be explained from three aspects: undercooling, dilution rate and microstructure type. From the upper surface of the cladding layer to the substrate, with the increasing dilution rate, the improvement of microhardness gradually decreases, so the appearance of peaks and valleys of the cladding layer has little to do with the dilution rate. Too large or too small undercooling reduces the microhardness of cladding layer by reducing the ratio of nucleation rate to crystal growth rate.

However, the special undercooling environment of the cladding layer (the undercooling is large at both ends and small in the middle) makes the microhardness of the cladding layer increase first, then decrease, then increase and then decrease, and accordingly the microhardness of the cladding layer changes as shown in Fig. 5. By adding WC particles to the cladding material, cracks can be eliminated and the microhardness of Cri2MoV cold die steel can be ensured.

Embodiment 3

This embodiment provides a laser cladding material of WC reinforced Ni6OAA. The raw materials are composed of WC particles (400 meshes) and Ni6OAA powder (100 meshes), and the mass ratio of WC particles to Ni6OAA powder is 2: 8;

NISOAA powder according to the mass ratio, uniformly mixing them, putting them into a planetary ball mill, ball milling with anhydrous ethanol as the ball milling medium and zirconia balls as the grinding ball, with the ball-to-material ratio of 3: 1 at the rotating speed of 350 r/min for 1 h, and drying at 70°C for 3 h after ball milling, thus obtaining the laser cladding material of WC reinforced NI60AA.

Comparative example 1 LU600595

Using NiGOAA powder (200 mesh) as laser cladding material, the laser cladding test was carried out, and the specific test method was the same as that in Embodiment 1.

The cladding layers of Embodiments 1- 3 were etched with aqua regia (VHCL:

VHNO3 = 3: 1) for 15 s. The microstructure of the cladding layers was observed by JSM- 7610F field emission scanning electron microscope, and it was found that the cladding layers were in good condition, with no obvious cracks and pores and dense structure.

The microhardness of the cladding layers obtained in Embodiments 1- 3 and

Comparative example 1 is shown in Table 1.

Table 1 Microhardness of cladding layer 1 2 3 example 1

As can be seen from the data in Table 1, the present invention can eliminate the cracks in the cladding layer while maintaining a high microhardness.

The above is only the preferred embodiment of the present invention, but the protection scope of the present invention is not limited to this, and any changes or substitutions that can be easily thought of by those familiar with the technical field within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A laser cladding material of WC reinforced NiGOAA, characterized in that the raw material consists of WC particles and Ni6OAA powder, and the mass ratio of the WC particles to the NiGOAA powder is (1-2): (8-9).

2. The laser cladding material of WC reinforced NiGOAA according to claim 1, characterized in that the raw materials are composed of WC particles and NiGOAA powder, and the mass ratio of the WC particles to the Ni6OAA powder is 1: 9.

3. The laser cladding material of WC reinforced NiGOAA according to claim 1, characterized in that the raw materials are composed of WC particles and NiGOAA powder, and the mass ratio of the WC particles to the Ni6OAA powder is 2: 8.

4. The laser cladding material of WC reinforced NiGOAA according to claim 1, characterized in that the particle size of the WC particles is 400 -500 mesh, and the particle size of the NiGOAA powder is 100-300 mesh.

5. A method for preparing the laser cladding material of WC reinforced NiGOAA according to any one of claims 1-4, characterized by comprising the following steps: accurately weighing WC particles and NiGOAA powder according to the mass ratio, uniformly mixing, ball milling and drying to obtain the laser cladding material of WC reinforced NiGOAA.

6. The preparation method of laser cladding material of WC reinforced NiGOAA according to claim 5, characterized in that during the ball milling, anhydrous ethanol is used as the ball milling medium, the grinding balls are zirconia balls, and the ball-to- material ratio is 3: 1.

7. The preparation method of laser cladding material of WC reinforced NiGOAA according to claim 5, characterized in that the rotation speed of ball milling is 300-350 r/min, and the time of ball milling is 1-2 h.

8. The preparation method of laser cladding material of WC reinforced NIGOAA 500595 according to claim 1, characterized in that the drying temperature is 70-80°C and the drying time is 2-3 h.