CN-121976184-A - Blue light ultra-high speed laser cladding copper-based composite coating for copper crystallizer and preparation method and application thereof

CN121976184ACN 121976184 ACN121976184 ACN 121976184ACN-121976184-A

Abstract

The invention relates to the technical field of metal additive manufacturing, in particular to a blue light ultra-high speed laser cladding copper-based composite coating for a copper crystallizer, and a preparation method and application thereof. The method comprises the steps of mixing copper metal powder with LaB 6 powder, carrying out sound resonance mixing to obtain composite copper alloy powder, preparing a first pure copper coating, a gradient structure coating and a second pure copper coating on a substrate respectively through laser cladding, and carrying out heat treatment to obtain the blue light ultra-high speed laser cladding copper-based composite coating for the copper crystallizer. According to the invention, the absorptivity of pure copper to laser is improved and the pure copper coating is modified by introducing LaB 6 powder, so that the gradient design strategy that the content of reinforced particles increases gradually from an inner layer to an outer layer is provided for reducing the difference between the coating and a matrix, and the controllable construction of the copper-based composite gradient coating with high strength, high wear resistance and high heat conductivity by cladding the high-reflection copper surface is realized by taking short wavelength blue laser as an energy source.

Inventors

GAO SHUOHONG
LONG HAIYANG
CHEN XIANG
ZHANG JIALONG
Zhong Geqia
LU BINGWEN
MI BAOJUN
XU JIAXIN
Wu Enru
QIU HAO
Yan xingchen
DONG ZHEN

Assignees

广东省科学院新材料研究所

Dates

Publication Date: 20260505
Application Date: 20260203

Claims (10)

1. The blue light ultra-high speed laser cladding copper-based composite coating for the copper crystallizer is characterized by comprising a pure copper coating and a gradient structure coating; The pure copper coating comprises a first pure copper coating and a second pure copper coating, wherein one surface of the first pure copper coating is connected with the substrate, and the other surface of the first pure copper coating, which is far away from the substrate, is connected with the gradient structure coating; the second pure copper coating is arranged around the gradient structure coating and is connected with the first pure copper coating; the gradient structure coating comprises a first composite coating, a second composite coating and a third composite coating which are sequentially connected, wherein one surface of the first composite coating is connected with a first pure copper coating; The first composite coating, the second composite coating and the third composite coating are all coatings prepared from copper powder and LaB 6 powder compound.
2. The blue-ray ultra-high-speed laser cladding copper-based composite coating for copper crystallizer according to claim 1, wherein the number of gradient structure coatings is not less than 2.
3. The blue light ultra-high speed laser cladding copper-based composite coating for a crystallizer according to claim 1, wherein the mass percentages of the LaB 6 powder in the first composite coating, the second composite coating and the third composite coating are sequentially increased.
4. The blue-ray ultra-high-speed laser cladding copper-based composite coating for a copper crystallizer according to claim 3, wherein the mass percentages of the LaB 6 powder in the first, second and third composite coatings are respectively (0.1 wt% -1.5 wt%), (1.5 wt% -3 wt%), (3 wt% -5 wt%).
5. The blue-ray ultra-high-speed laser cladding copper-based composite coating for a copper crystallizer according to claim 1, wherein the thickness of the first pure copper coating is 0.5-1.5mm, the thickness of the second pure copper coating is 3-4.5mm, the thickness of the first composite coating is 1-1.5mm, the thickness of the second composite coating is 1-1.5mm, the thickness of the third composite coating is 1-1.5mm, and the area ratio of the third composite coating area to the second pure copper coating area is 2-3:1 from the top view.
6. The method for preparing the blue light ultra-high speed laser cladding copper-based composite coating for the copper crystallizer as set forth in any one of claims 1 to 5, which is characterized by comprising the following steps: (1) Mixing copper metal powder with LaB 6 powder, and performing acoustic resonance mixing treatment to obtain composite copper alloy powder; (2) And respectively preparing a first pure copper coating, a gradient structure coating and a second pure copper coating on the substrate by using the copper metal powder and the composite copper alloy powder through laser cladding, and then carrying out heat treatment to obtain the blue light ultra-high speed laser cladding copper-based composite coating for the copper crystallizer.
7. The method according to claim 6, wherein the particle size of the LaB 6 powder in the step (1) is 30-80nm, the particle size of the copper metal powder is 50-150 μm, the acceleration of the sound resonance mixing treatment in the step (1) is 60-90g, the frequency is 40-80Hz, and the mixing time is 10-30min.
8. The preparation method of the laser cladding material according to claim 6, wherein the laser cladding in the step (2) is blue light ultra-high speed laser cladding, the power of the laser cladding is 800-1400W, the scanning rate of the laser cladding is 150-500 mm/s, the spot diameter of the laser cladding is 2-5mm, the lap rate of the laser cladding is 20-80%, the temperature of the heat treatment is 400-600 ℃, and the time of the heat treatment is 2-4 hours.
9. The method according to any one of claims 6 to 8, wherein the substrate in step (2) is subjected to pretreatment before use, the pretreatment including surface polishing, sand blasting and preheating, the preheating being performed at a temperature of 200 to 400 ℃, and the substrate being at least one of 316L, 42CrMo, T1, H90, QAl 5.
10. Use of a blue ultra-high speed laser cladding copper-based composite coating for copper crystalliser according to any of claims 1-5 for the production of heat-managed, electrically conductive and corrosion resistant parts.

Description

Blue light ultra-high speed laser cladding copper-based composite coating for copper crystallizer and preparation method and application thereof Technical Field The invention relates to the technical field of metal additive manufacturing, in particular to a blue light ultrahigh-speed laser cladding copper-based composite coating for a copper crystallizer, and a preparation method and application thereof. Background Pure copper such as copper crystallizers and alloys thereof are widely used for heat management, electrical conduction and corrosion resistant components which tend to be in service under complex conditions, particularly steel continuous casting copper crystallizers. The iron and steel industry is an important basic industry of national economy, is an indispensable supporting industry for realizing industrial modernization, and is the largest iron and steel producing country and consuming country in the current world. The copper crystallizer is the most critical casting blank forming part in continuous casting equipment, molten steel, casting powder, a blank shell and a copper wall of the crystallizer in a heat exchange system form a complex system with a coupling of a thermal state and a mechanical state, the working surface of the copper crystallizer bears the pressure of the molten steel, the friction force between the blank shell and the copper wall and the conduction of the heat of the molten steel, and the copper crystallizer is extremely easy to generate thermal deformation and surface abrasion failure under the combined action of mechanical stress and thermal stress. The surface failure caused by the copper crystallizer under the action of the severe working condition becomes one of the bottleneck problems for restricting the steel continuous casting technology to develop to a higher speed and a higher efficiency. Failure of any local position of the working face of the copper crystallizer can lead to advanced offline maintenance of the whole set of copper crystallizer, the continuous casting efficiency is reduced, the cost is increased, and huge economic loss and energy waste are caused by the failure of the crystallizer caused by corrosion and abrasion each year. Aiming at the problems that a copper crystallizer is easy to lose efficacy due to corrosion and abrasion and the traditional coating has defects, wang Zhihao et al adopt a laser cladding technology to prepare an iron-cobalt gradient coating on the surface of a Cu-Cr-Zr matrix (literature-study on the structure and performance of the copper crystallizer laser cladding iron-cobalt gradient layer), optimize the process by a paraxial synchronous powder feeding method so that a cobalt-based working layer generates gamma-Co solid solution in situ,Equal hard phase, realizing the hardness reaching 417.3The wear resistance is obviously improved (3.76 times of the base body), and the coating is compact and has no macroscopic defect. However, the scheme is difficult to adapt to complex and harsh continuous casting working conditions, the problem of comprehensive performance of wear resistance, corrosion resistance and impact resistance is not solved, thermal stress accumulation is still possibly caused by the difference of thermal expansion of the iron base and the copper base, the corrosion resistance is not tested, and the toughness of the casting blank under the impact of nodulation is not evaluated. Disclosure of Invention In order to solve the technical problems in the prior art, the invention aims to provide a blue light ultra-high speed laser cladding copper-based composite coating for a copper crystallizer, and a preparation method and application thereof so as to solve the technical problems. The existing pure copper or copper alloy has extremely high reflection on the conventional laser, the laser cladding preparation method of the copper-based composite coating has insufficient powder melting, more pores and general forming quality, and the comprehensive performance of the copper-based composite coating still needs to be further improved. Aiming at the problems existing in the prior art, the preparation method of the blue light ultrahigh-speed laser cladding copper-based composite coating for the copper crystallizer can improve the absorptivity of powder materials to laser, ensure that the reinforced particle phases are uniformly distributed, and is a special process for the high-strength high-wear-resistance high-heat-conductivity copper-based composite gradient coating suitable for short-wavelength blue laser cladding. According to a first aspect of the invention, the invention provides a blue light ultra-high speed laser cladding copper-based composite coating for a copper crystallizer and a preparation method thereof, comprising a pure copper coating and a gradient structure coating; the pure copper coating comprises a first pure copper coating (an inner layer is also called a bonding layer with a substrate) and a second pu