High-power laser cladding annular beam optical system based on conical mirror and double-ridge mirror
By using a high-power laser cladding ring optical system based on conical mirrors and double-roof mirrors, the problems of incomplete light spots and multi-wavelength laser transmission are solved, thereby improving the quality of the cladding layer and protecting the lens, and adapting to various laser processing needs.
Patent Information
- Application Number
- CN202621110762.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-22
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2036-07-22
AI Technical Summary
Existing conical ring spot systems result in incomplete spotting when feeding wire or powder at the center, and cannot achieve multi-wavelength laser transmission, which limits the improvement of cladding quality. In particular, the lens is easily damaged when processing highly reflective materials, and it is impossible to achieve integrated preheating-processing-post-heat treatment.
A high-power laser cladding ring optical system based on a conical mirror and a double-roof mirror is adopted. The two wavelength lasers are combined into coaxial parallel light through the beam combining unit. The conical mirror and double-roof mirror are used to convert it into vertical ring light. The preheating-processing-post-heat treatment are integrated through the focusing unit. The protective glass is coated with a dual-wavelength anti-reflection film, and the right-angle mirror is equipped with a through hole for feeding wire or powder.
It achieves a reduction in the temperature gradient of the molten pool during laser cladding, reduces defects such as pores and cracks, improves the bonding strength of the cladding layer, reduces the probability of lens damage, and can adapt to multi-wavelength laser processing, thereby improving the cladding quality.
Smart Images
Figure CN224678148U_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a high-power laser cladding ring spot optical system based on a conical mirror and a double-roof mirror, belonging to the field of laser processing. Background Technology
[0002] Laser cladding technology uses a laser beam to melt alloy powder or wire and rapidly solidify it on the surface of a substrate, forming a cladding layer that is metallurgically bonded to the substrate, thereby achieving surface modification and repair of materials. Traditional laser cladding often uses a Gaussian-distributed circular spot, which has concentrated energy at the center and rapid attenuation at the edges, resulting in a large temperature gradient in the molten pool. This easily leads to defects such as porosity, cracks, and residual stress, and the dilution rate of the cladding layer is difficult to control.
[0003] Ring-shaped laser spots possess the advantages of uniform energy distribution, small temperature gradient in the molten pool, and moderate cooling rate, which can significantly improve the quality of the cladding layer. Existing ring-shaped laser spot generation technologies mainly include the conical lens method, the diffractive optical element method, and the fiber bundle method. Among them, the conical lens method is widely used in high-power laser scenarios due to its simple structure, high energy utilization, and high damage threshold.
[0004] However, existing conical annular spot systems have a key problem: to achieve center wire or powder feeding, a reflector with a central opening needs to be placed in the optical path. This results in a permanent gap in the annular spot at the central opening, destroying the integrity of the spot and causing problems such as uneven cladding layer thickness and reduced bonding strength. Furthermore, most existing systems can only transmit a single wavelength of laser. When processing highly reflective laser materials such as copper, copper itself easily reflects the laser, leading to a high probability of burning the internal mirrors of the laser head. Moreover, it cannot achieve an integrated preheating-processing-post-heat treatment process, limiting further improvements in cladding quality. Utility Model Content
[0005] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a high-power laser cladding ring spot optical system based on a conical mirror and a double roof mirror, so as to solve the problems mentioned in the background technology.
[0006] To achieve the above objectives, this utility model is implemented through the following technical solution: a high-power laser cladding ring spot optical system based on a conical mirror and a double-roof mirror, comprising a beam combining unit, a conical mirror, a third collimating mirror, a ring spot conversion unit, and a focusing unit arranged sequentially along the optical path; The beam combining unit is used to combine the first wavelength laser and the second wavelength laser into a coaxial parallel beam. The conical lens is used to convert parallel light into outward-diverging ring light; The third collimating lens is used to collimate the diverging ring light into a parallel ring light. The ring-shaped light spot conversion unit is used to convert parallel ring light into vertical ring light; The focusing unit is used to focus the vertical ring light onto the surface of the workpiece.
[0007] Furthermore, the beam combining unit includes a first collimating mirror, a second collimating mirror, a plane mirror, and a beam splitter. The first collimating mirror is used to collimate the input first wavelength laser to obtain a collimated first wavelength laser. The second collimating mirror is used to collimate the input second wavelength laser to obtain a collimated second wavelength laser. The plane mirror is used to reflect the collimated second wavelength laser to obtain a second wavelength parallel laser. The plane mirror is placed at a 45° angle to the horizontal direction. The beam splitter is used to combine the collimated first wavelength laser and the second wavelength parallel laser into a coaxial parallel beam. The beam splitter is also placed at a 45° angle to the horizontal direction. Both the first collimating mirror and the second collimating mirror are made of fused silica.
[0008] Furthermore, the annular light spot conversion unit includes a first roof mirror, a right-angle mirror, and a second roof mirror. The first roof mirror is used to refract the parallel annular light and split the parallel annular light into two parallel semi-annular lights. The right-angle mirror is used to reflect two parallel semi-circular lights to obtain two vertical semi-circular lights. The second roof mirror is used to refract the two vertical semi-circular lights again and complete the two vertical semi-circular lights to form a vertical ring light.
[0009] Furthermore, a protective glass is provided below the focusing unit to protect the internal optical components from molten slag splashes. The protective glass is coated with a dual-wavelength anti-reflection film of 1064nm and 455nm. The focusing unit adopts a plano-convex lens. The plano-convex lens, the protective glass, and the conical lens are all made of fused silica.
[0010] Furthermore, the first wavelength laser is a 1064nm laser, corresponding to a high-power fiber laser; the second wavelength laser is a 455nm laser, corresponding to a semiconductor-assisted laser.
[0011] Furthermore, the right-angle reflector has a circular structure, and a through hole with a diameter of 8mm is provided at the center of the right-angle reflector. The through hole is used for feeding wire or powder, and the reflective surface of the right-angle reflector is coated with a dual-wavelength high-reflection film of 1064nm and 455nm.
[0012] Furthermore, the ridge angles of the first and second ridge mirrors are both 90°, and the parameters of the first and second ridge mirrors are exactly the same. The first and second ridge mirrors are symmetrically arranged about the right-angle reflector, and both the first and second ridge mirrors are made of fused silica.
[0013] The beneficial effects of this utility model are: A 1064nm high-power laser is output through the first collimating lens and incident on the beam splitter. A 455nm auxiliary laser is output through the second collimating lens and reflected by the plane mirror before being incident on the beam splitter. The beam splitter combines the 1064nm laser and the 455nm laser into a single coaxial parallel beam, realizing an integrated process of preheating, processing, and post-heat treatment. This effectively reduces the temperature gradient of the molten pool, reduces defects such as pores and cracks, improves the bonding strength of the cladding layer, and effectively reduces the probability of damage to components such as protective glass. Attached Figure Description
[0014] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the high-power laser cladding ring spot optical system based on a conical mirror and a double-roof mirror according to this utility model; Figure 2 This is a schematic diagram of the third collimating lens in the high-power laser cladding annular spot optical system based on a conical mirror and a double-roof mirror of this invention. Figure 3 This is a schematic diagram of the cone mirror in the high-power laser cladding annular spot optical system based on the cone mirror and double roof mirror of this utility model; Figure 4 This is a schematic diagram of the first roof mirror in the high-power laser cladding annular spot optical system based on a conical mirror and a double roof mirror of this invention; In the diagram: 1-First collimating lens, 2-Second collimating lens, 3-Plane mirror, 4-Beam splitter, 5-Cone, 6-Third collimating lens, 7-First roof mirror, 8-Right-angle mirror, 9-Second roof mirror, 10-Planto-convex lens. Detailed Implementation
[0015] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.
[0016] Please see Figures 1-4 This utility model provides a technical solution: a high-power laser cladding ring spot optical system based on a conical mirror 5 and a double roof mirror, comprising a beam combining unit, a conical mirror 5, a third collimating mirror 6, a ring spot conversion unit and a focusing unit arranged sequentially along the optical path. The beam combining unit includes a first collimating mirror 1, a second collimating mirror 2, a plane mirror 3 and a beam splitter 4. The ring spot conversion unit includes a first roof mirror 7, a right-angle mirror 8 and a second roof mirror 9. The focusing unit uses a plano-convex lens 10. A first collimating mirror 1, made of fused silica, is used to collimate the input first wavelength laser to obtain a collimated first wavelength laser, which is a 1064nm laser, corresponding to a high-power fiber laser. A second collimating mirror 2, made of fused silica, is used to collimate the input second wavelength laser to obtain a collimated second wavelength laser, which is a 455nm laser, corresponding to a semiconductor-assisted laser. A plane mirror 3, placed at a 45° angle to the horizontal, is used to reflect the collimated second wavelength laser to obtain a second wavelength parallel laser. A beam splitter 4, placed at a 45° angle to the horizontal, is used to collimate the first wavelength laser and the second wavelength parallel laser into a coaxial parallel beam. A conical lens 5 is used to convert the parallel beam into an outward diverging ring beam, and the apex angle of the conical lens 5 is designed according to the diameter of the required ring beam. A third collimating lens 6 is used to collimate the diverging ring beam into a parallel ring beam. A first roof lens 7, with a roof angle of 90°, is used to refract the parallel ring beam and split it into two parallel semi-ring beams. The circular right-angle reflector 8 is used to reflect two parallel semi-circular lights to obtain two vertical semi-circular lights. The center of the right-angle reflector 8 has a through hole with a diameter of 8mm, which is used for feeding wire or powder. The reflective surface of the right-angle reflector 8 is coated with a dual-wavelength high-reflectivity film of 1064nm and 455nm, with a reflectivity of ≥99.5%. The second roof mirror 9, with a ridge angle of 90°, is used to refract the two vertical semi-circular lights again, and to complete the two vertical semi-circular lights to form a vertical ring light. The first roof mirror 7 and the second roof mirror 9 are both made of fused silica material, and the parameters of the first roof mirror 7 and the second roof mirror 9 are exactly the same. The first roof mirror 7 and the second roof mirror 9 are symmetrically arranged about the right-angle reflector 8. The plano-convex lens 10, made of fused silica, is used to focus vertical ring light onto the surface of the workpiece. The focal length of the plano-convex lens 10 is designed to be 100mm-300mm depending on the required working distance. The protective glass, also made of fused silica, is placed below the focusing unit. The protective glass is used to protect the internal optical components from molten slag splashes. The protective glass is coated with a dual-wavelength anti-reflection film of 1064nm and 455nm.
[0017] During optical transmission, the 1064nm high-power fiber laser is output through the fiber and converted into a first wavelength laser by the first collimating mirror 1, which is then directly incident on the beam splitter 4. Simultaneously, the 455nm semiconductor auxiliary laser is converted into a second wavelength laser by the second collimating mirror 2, and then reflected by the plane mirror 3 to form a second wavelength parallel laser, which is then incident on the beam splitter 4. The beam splitter 4 has a transmittance of ≥99% for the 1064nm laser and a reflectance of ≥99% for the 455nm laser. Therefore, the beam splitter 4 will combine the 1064nm laser and the 455nm laser into a coaxial parallel beam. The beam combining unit can simultaneously transmit the 1064nm processing laser and the 455nm auxiliary laser, realizing an integrated process of preheating-processing-post-heat treatment. This effectively reduces the temperature gradient of the molten pool, reduces defects such as pores and cracks, improves the bonding strength of the cladding layer, and effectively reduces the probability of damage to components such as protective glass. After the combined parallel light is incident on the conical lens 5, it is converted into an outwardly diverging ring light under the refraction of the conical surface of the conical lens 5. The diverging ring light is incident on the third collimating lens 6 and collimated into a parallel ring light. By using the conical lens 5 and the third collimating lens 6, a parallel ring light with a constant diameter can be formed, which effectively reduces the probability of stray light and ensures the uniformity of the ring light energy density. When parallel ring light is incident on the first roof mirror 7, it is refracted by the two mutually perpendicular reflecting surfaces of the first roof mirror 7. At this time, a gap with a width equivalent to the roof line of the first roof mirror 7 will appear at the position of the parallel ring light, thus forming two parallel semi-ring lights. After two parallel semi-circular lights are incident on the right-angle mirror 8, they are reflected by the right-angle mirror 8 to obtain two vertical semi-circular lights. No light passes through the through-hole position, and the gaps of the two parallel semi-circular lights coincide with the gaps of the two vertical semi-circular lights. After the two vertical semi-circular lights are incident on the second roof mirror 9, they are refracted again. Based on the principle of light path reversibility, the gap of the light spot generated by the first roof mirror 7 is completely filled, forming a complete vertical ring light. This solves the problem of incomplete light spot caused by the central wire and powder feeding, and the energy distribution of the focused ring light spot is uniform. After the vertical parallel ring light is incident on the plano-convex lens 10, it is focused onto the workpiece surface below the protective glass, forming a ring spot with uniform energy distribution. At the same time, the wire feed tube or powder feed tube passes through the through hole of the right-angle reflector 8 to transport the welding wire or powder to the central area of the ring spot, realizing laser cladding processing. Furthermore, by changing the conical lens 5 with different apex angles or the plano-convex lens 10 with different focal lengths, the diameter and width of the ring spot can be flexibly adjusted to adapt to different cladding process requirements.
[0018] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A high-power laser cladding annular spot optical system based on a conical mirror and a double-roof mirror, characterized in that: It includes a beam combining unit, a conical lens (5), a third collimating lens (6), an annular spot conversion unit, and a focusing unit arranged sequentially along the optical path; The beam combining unit is used to combine the first wavelength laser and the second wavelength laser into a coaxial parallel beam. The conical lens (5) is used to convert parallel light into outward-diverging ring light; The third collimating lens (6) is used to collimate the diverging ring light into a parallel ring light; The ring-shaped light spot conversion unit is used to convert parallel ring light into vertical ring light; The focusing unit is used to focus the vertical ring light onto the surface of the workpiece; The ring light spot conversion unit includes a first roof mirror (7), a right-angle mirror (8), and a second roof mirror (9). The first roof mirror (7) is used to refract the parallel ring light and split the parallel ring light into two parallel semi-ring lights. The right-angle mirror (8) is used to reflect two parallel semi-circular lights to obtain two vertical semi-circular lights. The second roof mirror (9) is used to refract the two vertical semi-circular lights again and complete the two vertical semi-circular lights to form a vertical ring light.
2. The high-power laser cladding annular spot optical system based on a conical mirror and a double-roof mirror according to claim 1, characterized in that: The beam combining unit includes a first collimating mirror (1), a second collimating mirror (2), a plane mirror (3), and a beam splitter (4). The first collimating mirror (1) is used to collimate the input first wavelength laser to obtain a collimated first wavelength laser. The second collimating mirror (2) is used to collimate the input second wavelength laser to obtain a collimated second wavelength laser. The plane mirror (3) is used to reflect the collimated second wavelength laser to obtain a second wavelength parallel laser. The plane mirror (3) is placed at a 45° angle to the horizontal direction. The beam splitter (4) is used to combine the collimated first wavelength laser and the second wavelength parallel laser into a coaxial parallel beam. The beam splitter (4) is placed at a 45° angle to the horizontal direction. Both the first collimating mirror (1) and the second collimating mirror (2) are made of fused silica.
3. The high-power laser cladding annular spot optical system based on a conical mirror and a double-roof mirror according to claim 1, characterized in that: The focusing unit is provided with a protective glass below it. The protective glass is used to protect the internal optical components from molten slag splashes. The protective glass is coated with a dual-wavelength anti-reflection film of 1064nm and 455nm. The focusing unit adopts a plano-convex lens (10). The plano-convex lens (10), the protective glass and the conical lens (5) are all made of fused silica.
4. The high-power laser cladding annular spot optical system based on a conical mirror and a double-roof mirror according to claim 1, characterized in that: The first wavelength laser is a 1064nm laser, corresponding to a high-power fiber laser; the second wavelength laser is a 455nm laser, corresponding to a semiconductor-assisted laser.
5. The high-power laser cladding annular spot optical system based on a conical mirror and a double-roof mirror according to claim 1, characterized in that: The right-angle mirror (8) has a circular structure. A through hole with a diameter of 8 mm is provided at the center of the right-angle mirror (8). The through hole is used for feeding wire or powder. The reflective surface of the right-angle mirror (8) is coated with a dual-wavelength high-reflection film of 1064 nm and 455 nm.
6. The high-power laser cladding annular spot optical system based on a conical mirror and a double-roof mirror according to claim 1, characterized in that: The first ridge mirror (7) and the second ridge mirror (9) both have a ridge angle of 90°, and the parameters of the first ridge mirror (7) and the second ridge mirror (9) are exactly the same. The first ridge mirror (7) and the second ridge mirror (9) are arranged symmetrically about the right-angle reflector (8), and the first ridge mirror (7) and the second ridge mirror (9) are both made of fused silica.