CN107505715B

CN107505715B - Complete annular laser cladding head

Info

Publication number: CN107505715B
Application number: CN201710790666.5A
Authority: CN
Inventors: 沈茂田; 练国富; 许明三; 韦铁平
Original assignee: Fujian University of Technology
Current assignee: Fujian University of Technology
Priority date: 2017-09-05
Filing date: 2017-09-05
Publication date: 2020-05-05
Anticipated expiration: 2037-09-05
Also published as: CN107505715A

Abstract

A complete annular laser cladding head comprises a laser head assembly, an annular plano-concave lens group, an annular Faraday optical rotator group and an annular plano-convex lens group which are sequentially arranged from top to bottom; the laser head assembly consists of a plurality of laser heads which are arranged in a ring shape; the laser device also comprises a metal powder feeding pipe, a protective gas pipe and a cooling liquid conveying pipe which are respectively arranged in the gaps of the laser heads. The laser head assembly is formed by that a high-power laser generates laser beams, the laser beams are divided into 8 laser beams by a 1 x 8 optical fiber coupler so that a metal powder feeding pipe, a protective gas pipe and a cooling liquid conveying pipe can enter the center of an annular laser beam, and then the 8 laser beams are synthesized into the annular laser beam by utilizing an annular plano-concave lens group, an annular Faraday optical rotator group and an annular plano-convex lens group. The invention provides a complete annular laser cladding head, which achieves the aim that a laser beam has no gap, and improves the coupling effect of the laser beam and powder, the thermal action efficiency and the utilization rate of metal powder.

Description

Complete annular laser cladding head

[ technical field ] A method for producing a semiconductor device

The invention belongs to the technical field of laser cladding, and particularly relates to a complete annular laser cladding head.

[ background of the invention ]

In the existing laser cladding technology, the powder feeding mode adopted for forming is that powder is fed outside a single powder tube and powder is fed coaxially outside a multi-powder tube. The smooth outside lateral powder feeding forming has some disadvantages: the powder conveyed in the inclined side direction generally moves in a parabola shape, the convergence precision of multiple powder beams is low, the movement track of the powder is interfered by multiple factors, the density distribution of the powder on the cross section of any optical axis is uneven, the coupling effect of laser beams and the powder is not high, the thermal action efficiency is low, the surface of a formed part is rough, and the utilization rate of the metal powder is generally only 20% -30%. In addition, the hollow powder tube in the light beam is arranged in the middle, powder is fed in the light, and three gaps are formed in the laser beam due to the fact that the laser head needs the light inner powder tube, the protective gas tube and the cooling liquid conveying tube.

Chinese utility model patent 201320761615.7 discloses a parallel annular laser cladding head, through at the inside three conical surface mirror that sets up of casing, incident beam assembles formation parallel annular light through last conical surface mirror, inner wall conical surface mirror and lower conical surface mirror reflection in proper order, has avoided effectively assembling the complicated layer height control problem that the light beam brought, improves the shaping quality, reduces the production and processing cost. Meanwhile, the adjusting mechanism is arranged to adjust the position of the conical mirror, the conical mirror is adjusted to move up and down according to needs, the duty ratio of the reflected light beam is adjusted, and a large number of experiment and production requirements are met. The disadvantages are that: the utilization rate of the metal powder is generally only 80-90%, and the up-and-down moving device for adjusting the conical mirror is complex and has high manufacturing cost.

Chinese patent 201510968684.9 discloses a split laser focusing coaxial fuse laser head and a laser coaxial fuse forming device, wherein the split laser focusing coaxial fuse laser head includes a beam splitting lens, a plurality of reflectors and a plurality of focusing lenses, the beam splitting lens can split the received parallel laser into a plurality of branch laser beams which are directed to each reflector one by one, the reflectors and the focusing lenses are arranged in one-to-one correspondence, and each focusing lens can focus the branch laser beams reflected by the corresponding reflector and then converge into a common focus. The beam splitting laser focusing coaxial fuse laser head and the laser coaxial fuse forming equipment realize laser beam splitting by utilizing transmission refraction so as to realize coaxial feeding of wires; therefore, isotropic laser fuse deposition of a two-dimensional plane is realized, and the anisotropic lateral wire feeding scanning deposition is solved. The disadvantages are that: the beam splitting lens, the plurality of reflectors and the plurality of focusing lens devices are complex, the manufacturing cost is high, and the utilization rate of metal powder is only 80-90 percent generally.

The Chinese utility model patent 201420857433.4 discloses an integrated laser cladding head, which comprises a semiconductor laser, an optical focusing system, a gas protection device, a dust removing device and a powder feeding head, which are arranged from top to bottom in sequence, wherein the dust removing device and the gas protection device are connected with a cooling device; the optical focusing system is provided with a light spot module. As optimization, the light spot module arranged on the optical focusing system is detachable. And the dust removal device and the gas protection device are externally connected with a cooling device. The optical focusing system comprises a circular light spot module, a rectangular light spot module and a linear light spot module. The circular light spot module, the rectangular light spot module and the linear light spot module are longitudinally arranged and can respectively move transversely. The disadvantages are that: the optical focusing system is complex in arrangement and high in manufacturing cost, and the utilization rate of metal powder is generally only 80% -90%.

Chinese patent application CN00807487.9 discloses an optical pickup head which reduces the difference in the optimum tilt angle due to coma aberration occurring with respect to another medium when the objective lens is adjusted to be the most suitable tilt with respect to one medium in an optical system in which optical systems corresponding to optical discs of different specifications are made common. The position of the 2 nd light source in the optical axis direction is set on the side farther from the objective lens than the position where the wavefront aberration is minimum. With this, the amount of increase of coma aberration when the tilt angle of the objective lens with respect to the 2 nd optical information recording medium is changed is reduced. Further, it is more preferable that the light source is set at a position where the coma aberration does not change with respect to the change of the tilt angle of the objective lens. This position is between the position where the wavefront aberration is minimum and the position where the optical system becomes infinite, and it is possible to suppress an increase in the difference in the operating distance between the two optical information recording media while suppressing an increase in the size of the optical head. The disadvantages are that: the coma image generated by the laser of the optical disk is difficult to adjust, the time and the day are wasted, and the utilization rate of the metal powder is lower than that of the common annular laser cladding head.

[ summary of the invention ]

The invention aims to provide a complete annular laser cladding head, which achieves the aim that a laser beam has no gap, and improves the coupling effect of the laser beam and powder, the thermal action efficiency and the utilization rate of metal powder.

The invention is realized by the following steps:

a complete annular laser cladding head comprises a laser head assembly, an annular plano-concave lens group, an annular Faraday optical rotator group and an annular plano-convex lens group which are sequentially arranged from top to bottom; the laser head assembly consists of a plurality of laser heads which are arranged in a ring shape;

also comprises a metal powder feeding pipe, a protective gas pipe and a cooling liquid conveying pipe; the metal powder feeding pipe, the protection air pipe and the cooling liquid conveying pipe are respectively arranged in the gaps of the laser heads.

Furthermore, the laser head assembly is characterized in that a high-power laser generates laser beams, the laser beams are divided into 8 laser beams through a 1 x 8 optical fiber coupler, so that the metal powder feeding pipe, the protective gas pipe and the cooling liquid conveying pipe can enter the center of the annular laser beams, and then the 8 laser beams are combined into the annular laser beams by utilizing the annular plano-concave lens group, the annular Faraday optical rotator group and the annular plano-convex lens group.

The invention has the advantages that: 1. the laser cladding light inner powder feeding pipe, the protective gas pipe and the cooling liquid conveying pipe are fed into the laser cladding head from the outside of the optical fiber, and the laser is fed into the outer ring of the laser cladding head from the optical fiber and is changed into an annular laser beam through an optical system. The laser beam is not influenced, no gap is formed in the laser beam, the coupling effect of the laser beam and powder is improved, the thermal action efficiency is improved, and the utilization rate of metal powder is increased. 2. The hollow powder tube of the laser cladding laser beam is centered, powder is fed in the light, the laser beam has no gap, and the laser cladding head is completely annular.

[ description of the drawings ]

The invention will be further described with reference to the following examples with reference to the accompanying drawings.

Fig. 1 is a schematic perspective view of the present invention.

Fig. 2 is a schematic diagram of the optical principle of the plano-concave lens of the present invention.

FIG. 3 is a schematic diagram of the structure of the annular plano-concave lens group of the present invention.

Figure 4 is a schematic diagram of the structure of a faraday rotator of the present invention.

Figure 5 is a schematic diagram of the structure of a circular faraday rotator group according to the present invention.

Fig. 6 is a schematic diagram of the optical principle of the plano-convex lens of the present invention.

FIG. 7 is a schematic view of the structure of the annular plano-convex lens assembly of the present invention.

Fig. 8 is a cross-sectional view of the present invention.

[ detailed description ] embodiments

Referring to fig. 1, a complete ring laser cladding head includes a laser head assembly 1, a ring plano-concave lens group 2, a ring faraday rotator group 3, and a ring plano-convex lens group 4, which are sequentially disposed from top to bottom; the laser head assembly 1 is made by dividing a laser beam generated by a high-power laser into 8 laser beams through a 1 x 8 fiber coupler.

Also comprises a metal powder feeding pipe 5, a protective gas pipe 6 and a cooling liquid conveying pipe 7; the metal powder feeding pipe 5, the protective gas pipe 6 and the cooling liquid conveying pipe 7 are respectively arranged in the gaps of the laser cladding heads.

The invention divides laser beams generated by a high-power laser into 8 beams by using an optical fiber coupler 1 x 8, and the beams are sent to the outer ring of the arranged annular laser cladding head through the optical fiber, and the purpose is that a metal powder feeding pipe 5, a protective gas pipe 6 and a cooling liquid conveying pipe 7 can enter the annular laser and cannot interfere with the annular laser beams. 8 laser beams are arranged on the outer ring of the laser cladding head and are changed into annular laser beams through an optical system. The optical system is as follows: an annular plano-concave lens group 2 for diffusing a single 8 laser beam into an annular laser beam. FIG. 2 shows the principle of plano-concave lens and optics, and FIG. 3 shows the structure of an annular plano-concave lens set; and a ring-shaped Faraday rotator group 3 for converting the ring-shaped laser beam into a ring-shaped parallel laser beam and preventing the laser beam from being reflected. FIG. 4 shows a Faraday rotator, and FIG. 5 shows a schematic structure of a ring-shaped Faraday rotator set; and a ring plano-convex lens group 4 for condensing the ring-shaped parallel laser beam into a ring-shaped laser spot. Fig. 6 shows the principle of plano-convex lens and optics, and fig. 7 shows the schematic structure of the annular plano-convex lens set.

The high-power laser generates laser beam, and the laser beam is divided into 8 laser beams by 1X 8 optical fiber coupler, and then the laser beam is changed into annular laser beam by optical system, its energy loss is very small, so that the metal powder-feeding tube, protective gas tube and cooling liquid conveying tube can be fed into the annular laser, and can not interfere with the annular laser beam, so that it can obtain no gap in the laser beam, and can raise coupling effect of laser beam and powder, its heat action efficiency and metal powder utilization rate can be up to above 90%. Fig. 8 shows a cross-sectional view of a complete ring laser cladding head.

The above description is only an example of the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A complete annular laser cladding head which is characterized in that:

comprises a laser head component, an annular plano-concave lens group, an annular Faraday optical rotator group and an annular plano-convex lens group which are sequentially arranged from top to bottom; the laser head assembly consists of a plurality of laser heads which are arranged in a ring shape;

2. The full ring laser cladding head of claim 1, wherein: the laser head assembly is characterized in that a high-power laser generates laser beams, the laser beams are divided into 8 laser beams through a 1 x 8 optical fiber coupler, so that the metal powder feeding pipe, the protective gas pipe and the cooling liquid conveying pipe can enter the center of the annular laser beams, and then the 8 laser beams are synthesized into the annular laser beams by utilizing the annular plano-concave lens group, the annular Faraday optical rotator group and the annular plano-convex lens group.