阅读说明：本技术 一种硬脆材料复杂构件飞秒激光精密成型加工系统 (Femtosecond laser precision forming processing system for complex hard and brittle material component ) 是由 雷名威 王军龙 李本海 江淮 高文焱 李广 李凯 侯振兴 张路 于 2019-10-28 设计创作，主要内容包括：一种硬脆材料复杂构件飞秒激光精密成型加工系统,包括飞秒激光器、激光调谐模块、机械光闸、激光偏振模块、可变倍扩束器、平面反射镜、光学衍射元件、成丝改质模块、成丝辅助件、装夹专用工装、多轴联动电控位移台、工控机、机械臂、化学腐蚀池和碱性中和池。通过可变倍扩束器、光学衍射元件和成丝改质模块调控飞秒激光成丝长度与直径,实现硬脆材料大深径比加工；通过成丝辅助件避免成丝前端加工一致性差的不良影响；通过机械光闸、多轴联动电控位移台和工控机等光机电协同控制,完成复杂构件激光改质功能；本发明具有加工深径比大、加工品质优良、可成型复杂构件、操作全自动化等优点,在航空航天、半导体、电子工业等领域具有广泛的应用前景。(The femtosecond laser precision forming processing system comprises a femtosecond laser, a laser tuning module, a mechanical optical gate, a laser polarization module, a variable-power beam expander, a plane reflector, an optical diffraction element, a filamentation modification module, a filamentation auxiliary part, a special clamping tool, a multi-axis linkage electric control displacement table, an industrial personal computer, a mechanical arm, a chemical corrosion tank and an alkaline neutralization tank. The length and the diameter of the femtosecond laser filamentation are regulated and controlled through a variable power beam expander, an optical diffraction element and a filamentation modification module, so that the processing of the hard and brittle material with large depth-diameter ratio is realized; the adverse effect of poor processing consistency of the front end of the filamentation is avoided through the filamentation auxiliary part; the laser modification function of the complex component is completed through the optical-mechanical-electrical cooperative control of a mechanical optical gate, a multi-axis linkage electric control displacement table, an industrial personal computer and the like; the invention has the advantages of large processing depth-diameter ratio, excellent processing quality, capability of forming complex components, full automation of operation and the like, and has wide application prospect in the fields of aerospace, semiconductors, electronic industry and the like.)

1. The utility model provides a complicated component femtosecond laser precision forming system of hard brittle material which characterized in that: the device comprises a femtosecond laser, a laser tuning module, a mechanical optical gate, a laser polarization module, a variable-magnification beam expander, a plane reflector, an optical diffraction element, a filamentation modification module and a filamentation auxiliary part;

the femtosecond laser is used for generating a femtosecond laser pulse beam, and the working wavelength of the femtosecond laser pulse beam is adjusted through a laser tuning module; the mechanical optical gate is used for controlling the laser transmission light path to be rapidly switched on and switched off, and the laser polarization module is used for adjusting the polarization state of the femtosecond laser pulse beam passing through the mechanical optical gate;

the variable-magnification beam expander is used for continuously adjusting the beam diameter of a femtosecond laser pulse beam, then adjusting a laser transmission light path through the plane reflector, enabling the femtosecond laser pulse beam to vertically enter the optical diffraction element, the optical diffraction element is used for laser beam space shaping, modulating laser space light intensity distribution and outputting a long focal depth beam, then integrally reducing the shaped beam according to a fixed proportion through the filamentation modification module, enhancing the laser power density to the material threshold of a workpiece to be processed, and completing filamentation modification inside the workpiece to be processed;

the filamentation auxiliary part covers the surface of the workpiece to be processed, so that the femtosecond laser filamentation front end with unstable power density is prevented from acting on the workpiece to be processed, and the filamentation modification consistency of the workpiece to be processed is improved.

2. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 1, wherein: the device also comprises a special clamping tool, a multi-axis linkage electric control displacement table, an industrial personal computer, a mechanical arm, a chemical corrosion tank and an alkaline neutralization tank;

the workpiece to be machined is fixed through the special clamping tool, and the middle of the upper surface of the special clamping tool is hollowed out to prevent laser from damaging the special clamping tool; then, the multi-axis linkage electric control displacement table is used for completing the uniform motion of a three-dimensional complex path of the special clamping tool fixed on the multi-axis linkage electric control displacement table, and the industrial personal computer is used for cooperatively controlling the mechanical optical gate and the multi-axis linkage electric control displacement table to complete the laser processing of the complex component;

the mechanical arm is used for moving a workpiece to be machined into a chemical corrosion tank after laser machining is finished, performing femtosecond laser filamentation modification area chemical corrosion to remove materials, moving the workpiece to be machined into an alkaline neutralization tank after the chemical corrosion is finished, neutralizing residual corrosive liquid of the workpiece to be machined, and finishing the precise forming machining of the complex component made of the hard and brittle material.

3. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 1 or 2, wherein: the femtosecond laser pulse beam generated by the femtosecond laser has wavelength of 750nm to 1100nm, pulse width of 10fs to 900fs, pulse energy of 10 muJ to 1mJ, pulse repetition rate of 1KHz to 1MHz, and laser beam quality M²≤1.5。

4. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 1 or 2, wherein: the laser tuning module is an optical parametric amplifier, laser after tuning is difference frequency signal light with the wavelength ranging from 1300nm to 2000nm, and the switching response time of the mechanical optical gate is less than or equal to 1 ms.

5. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 1 or 2, wherein: the laser polarization module is a combination of a half-wave plate and a quarter-wave plate, the half-wave plate is placed in front of the quarter-wave plate, and the maximum magnification of the variable power beam expander is in the range of 2X to 10X; the incident angle of the plane mirror is 45 degrees +/-5 degrees.

6. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 1 or 2, wherein: the optical diffraction element is a cone lens having a cone angle in the range of 1 ° to 40 °.

7. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 1 or 2, wherein: the filamentation modification module is a micro-focusing system which is composed of a large-focus lens and a small-focus objective lens and has the multiplying power of 5X-50X, wherein the focal length of the lens is within the range of 100mm to 500mm, the focal length of the objective lens is within the range of 10mm to 40mm, and the lens and the objective lens are coaxially arranged in a confocal point.

8. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 1 or 2, wherein: the filamentation auxiliary member is a double-sided polished fused quartz plate with a thickness in the range of 0.3mm to 2mm and a diameter in the range of 15mm to 310 mm.

9. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 2, wherein: the concentration of the HF solution in the chemical corrosion tank is within the range of 1% to 30%, and the soaking time of the workpiece to be processed in the chemical corrosion tank is within the range of 1h to 120 h;

the concentration of NaOH solution in the alkaline neutralization tank is in the range of 0.1 to 10 percent, and the soaking time of the workpiece to be processed in the alkaline neutralization tank is in the range of 0.1 to 1 hour.

10. The femtosecond laser precision forming system for the complex component made of the hard and brittle material as claimed in claim 2, wherein: the multi-axis linkage electric control displacement platform is a three-axis motion platform, the positioning precision of an X/Y axis is less than or equal to 10 mu m, the stroke of a Z axis is more than or equal to 10mm, and the size of the special clamping tool is within the range of 10mm to 300 mm.

Technical Field

The invention belongs to the technical field of laser precision manufacturing, and particularly relates to a femtosecond laser precision forming processing system for a complex component made of a hard and brittle material based on filamentation modification and chemical corrosion.

Background

By virtue of a series of advantages of stable performance, high mechanical strength, strong insulating property, good optical property and the like, hard and brittle materials such as lithium niobate crystals, quartz glass, tempered glass and the like occupy an important position in the fields of aerospace, semiconductors, electronic industry and the like. With the rapid development of the application field, the requirements on the forming size precision and the processing efficiency of the complex component made of the hard and brittle material are higher and higher.

At present, machining equipment for mechanical cutting, long-pulse laser hot melting and femtosecond laser modification is mainly adopted for the complex component made of the hard and brittle material. The machining equipment of mechanical cutting and long pulse laser hot melting has the technical bottlenecks of large residual stress, serious surface pollution, poor dimensional precision and the like; in addition, the nonlinear optical effect and the plasma effect in the femtosecond laser filamentation modification process easily cause the quality problems of subsurface damage, microscopic defects, poor processing consistency and the like. Therefore, it is urgently required to develop a precision molding processing system applicable to a complex member made of a hard and brittle material.

In order to improve the forming and processing precision of the complex component, avoid subsurface damage and microscopic defects and improve the processing consistency, a femtosecond laser precision forming and processing system for the complex component made of hard and brittle materials based on filamentation modification and chemical corrosion needs to be researched.

Disclosure of Invention

The invention aims to provide a femtosecond laser precision forming processing system of a complex hard and brittle material component based on filamentation modification and chemical corrosion, and solves the problems of low forming processing dimensional precision and poor processing quality of the existing equipment in the prior art. The system has the advantages of high forming size precision, excellent processing quality, full-automatic operation and the like.

The technical scheme adopted by the invention is as follows:

a femtosecond laser precision forming processing system for a complex component made of hard and brittle materials comprises a femtosecond laser, a laser tuning module, a mechanical optical shutter, a laser polarization module, a variable-power beam expander, a plane reflector, an optical diffraction element, a filamentation modification module and a filamentation auxiliary piece;

the femtosecond laser is used for generating a femtosecond laser pulse beam, and the working wavelength of the femtosecond laser pulse beam is adjusted through a laser tuning module; the mechanical optical gate is used for controlling the laser transmission light path to be rapidly switched on and switched off, and the laser polarization module is used for adjusting the polarization state of the femtosecond laser pulse beam passing through the mechanical optical gate;

the variable-magnification beam expander is used for continuously adjusting the beam diameter of a femtosecond laser pulse beam, then adjusting a laser transmission light path through the plane reflector, enabling the femtosecond laser pulse beam to vertically enter the optical diffraction element, the optical diffraction element is used for laser beam space shaping, modulating laser space light intensity distribution and outputting a long focal depth beam, then integrally reducing the shaped beam according to a fixed proportion through the filamentation modification module, enhancing the laser power density to the material threshold of a workpiece to be processed, and completing filamentation modification inside the workpiece to be processed;

the filamentation auxiliary part covers the surface of the workpiece to be processed, so that the femtosecond laser filamentation front end with unstable power density is prevented from acting on the workpiece to be processed, and the filamentation modification consistency of the workpiece to be processed is improved.

Furthermore, the femtosecond laser precision forming processing system for the complex component made of the hard and brittle material also comprises a special clamping tool, a multi-axis linkage electric control displacement table, an industrial personal computer, a mechanical arm, a chemical corrosion tank and an alkaline neutralization tank;

the workpiece to be machined is fixed through the special clamping tool, and the middle of the upper surface of the special clamping tool is hollowed out to prevent laser from damaging the special clamping tool; then, the multi-axis linkage electric control displacement table is used for completing the uniform motion of a three-dimensional complex path of the special clamping tool fixed on the multi-axis linkage electric control displacement table, and the industrial personal computer is used for cooperatively controlling the mechanical optical gate and the multi-axis linkage electric control displacement table to complete the laser processing of the complex component;

the mechanical arm is used for moving a workpiece to be machined into a chemical corrosion tank after laser machining is finished, performing femtosecond laser filamentation modification area chemical corrosion to remove materials, moving the workpiece to be machined into an alkaline neutralization tank after the chemical corrosion is finished, neutralizing residual corrosive liquid of the workpiece to be machined, and finishing the precise forming machining of the complex component made of the hard and brittle material.

Furthermore, the femtosecond laser pulse beam generated by the femtosecond laser has a wavelength ranging from 750nm to 1100nm, a pulse width ranging from 10fs to 900fs, a pulse energy ranging from 10 muJ to 1mJ, a pulse repetition rate ranging from 1KHz to 1MHz, and a laser beam mass M²≤1.5。

Furthermore, the laser tuning module is an optical parametric amplifier, the laser after tuning is difference frequency signal light with the wavelength ranging from 1300nm to 2000nm, and the switching response time of the mechanical optical shutter is less than or equal to 1 ms.

Further, the laser polarization module is a combination of a half-wave plate and a quarter-wave plate, the half-wave plate is placed in front of the quarter-wave plate, and the maximum magnification of the variable power beam expander is in the range of 2X to 10X; the incident angle of the plane mirror is 45 degrees +/-5 degrees.

Further, the optical diffraction element is a cone lens having a cone angle in a range of 1 ° to 40 °.

Further, the filamentation modification module is a micro-focusing system which is composed of a large-focus lens and a small-focus objective lens and has the multiplying power of 5X-50X, wherein the focal length of the lens is within the range of 100mm to 500mm, the focal length of the objective lens is within the range of 10mm to 40mm, and the lens and the objective lens are coaxially arranged in a confocal point.

Further, the filamentation auxiliary member is a double-sided polished fused quartz plate with a thickness in the range of 0.3mm to 2mm and a diameter in the range of 15mm to 310 mm.

Further, the concentration of the HF solution in the chemical corrosion tank is within the range of 1% to 30%, and the soaking time of the workpiece to be processed in the chemical corrosion tank is within the range of 1h to 120 h;

the concentration of NaOH solution in the alkaline neutralization tank is in the range of 0.1 to 10 percent, and the soaking time of the workpiece to be processed in the alkaline neutralization tank is in the range of 0.1 to 1 hour.

Furthermore, the multi-axis linkage electric control displacement platform is a three-axis motion platform, the positioning precision of an X/Y axis is less than or equal to 10 microns, the stroke of a Z axis is more than or equal to 10mm, and the size of the special clamping tool is within the range of 10mm to 300 mm.

Compared with the prior art, the invention has the following beneficial effects:

(1) compared with the current forming and processing equipment for the complex component made of the hard and brittle material, the system of the invention adopts the femtosecond laser, and the thermal stress is reduced because the femtosecond laser has extremely short duration, thereby reducing the sub-surface damage and the microscopic defect; meanwhile, high-transmittance laser of the workpiece to be processed is output through the laser tuning module, and the inside of the material is modified through filamentation, so that the surface pollution of the workpiece is avoided.

(2) Compared with the current forming and processing equipment for the complex member made of the hard and brittle material, the system provided by the invention has the advantages that the traditional Gaussian beam is shaped into the Bessel beam with longer focal depth through the optical diffraction element, the femtosecond laser is facilitated to form a section of millimeter-magnitude optical fiber, the single scanning processing depth of the laser is increased to 1mm from 10 mu m, and the processing efficiency is improved by 2 magnitudes.

(3) Compared with the current forming and processing equipment for complex components made of hard and brittle materials, the system can integrally reduce the diameter of a light beam at a focus to carry out modification according to a fixed proportion through the variable-power beam expander and the filamentation modification module consisting of the large-focus lens and the small-focus objective lens, improves the laser forming and processing precision by 1 order of magnitude to 1 mu m, and realizes the forming and processing depth-diameter ratio of 1000.

(4) Compared with the current forming and processing equipment for complex components made of hard and brittle materials, the system disclosed by the invention covers the workpiece to be processed with the filamentation auxiliary part, and the laser filamentation front end with poor stability acts on the filamentation auxiliary part, so that the filamentation middle end with good stability is used for the workpiece to be processed, the adverse effect of the workpiece to be processed caused by unstable power density of the filamentation front end is avoided, and the forming and processing consistency of femtosecond laser is ensured.

(5) Compared with the current forming and processing equipment for complex components made of hard and brittle materials, the system integrates three functional areas, namely a special clamping tool, a chemical corrosion tank and an alkaline neutralization tank, and realizes full-automatic operation of three procedures, namely laser filamentation modification, acid liquor corrosion forming and alkaline neutralization cleaning, by loading, unloading and transferring a workpiece to be processed through a mechanical arm, so that the operation is convenient and simple.

Drawings

FIG. 1 is a schematic diagram of a femtosecond laser precision forming system for complex components made of hard and brittle materials.

The reference numbers illustrate:

101-femtosecond laser; 102-a laser tuning module; 103-mechanical shutter; 104-laser polarization module; 105-a variable power beam expander; 106-plane mirror; 107-an optical diffraction element; 108-filamentation modifying module; 109-a filamentation aid; 110-a workpiece to be processed; 111-clamping special tooling; 112-multi-axis linkage electric control displacement table; 113-an industrial personal computer; 114-mechanical arm, 115-chemical etching tank, 116-alkaline neutralization tank.

Detailed Description

The following further describes the embodiments of the present invention with reference to the drawings.

The invention discloses a femtosecond laser precision forming processing system for a complex component made of hard and brittle materials based on filamentation modification and chemical corrosion, and belongs to the technical field of laser precision manufacturing. The invention discloses a femtosecond laser precision forming processing system for a complex component made of hard and brittle materials, which comprises a femtosecond laser, a laser tuning module, a mechanical optical gate, a laser polarization module, a variable-magnification beam expander, a plane reflector, an optical diffraction element, a filamentation modification module, a filamentation auxiliary part, a special clamping tool, a multi-axis linkage electric control displacement table, an industrial personal computer, a mechanical arm, a chemical corrosion tank and an alkaline neutralization tank.

The length and the diameter of the femtosecond laser filamentation are regulated and controlled through a variable power beam expander, an optical diffraction element and a filamentation modification module, so that the processing of the hard and brittle material with large depth-diameter ratio can be realized; the negative influence of poor consistency of the processing of the front end of the wire forming is avoided through the wire forming auxiliary part, and the processing quality of the hard and brittle material is greatly improved; the laser modification function of the complex component is completed through the optical-mechanical-electrical cooperative control of a mechanical optical gate, a multi-axis linkage electric control displacement table, an industrial personal computer and the like; the full-automatic operation of laser-induced chemical corrosion precision forming is realized through a mechanical arm, a chemical corrosion tank and an alkaline neutralization tank; the processing system has the advantages of large processing depth-diameter ratio, excellent processing quality, capability of forming complex components, full automation of operation and the like, and has wide application prospect in the fields of aerospace, semiconductors, electronic industry and the like.

Specifically, as shown in fig. 1, the femtosecond laser precision forming system for a complex member of a hard and brittle material based on filamentation modification and chemical corrosion provided by the invention comprises a femtosecond laser, a laser tuning module, a mechanical optical shutter, a laser polarization module, a variable-magnification beam expander, a plane mirror, an optical diffraction element, a filamentation modification module, a filamentation auxiliary part, a special clamping tool, a multi-axis linkage electric control displacement table, an industrial personal computer, a mechanical arm, a chemical corrosion tank and an alkaline neutralization tank.

The femtosecond laser is used for generating an ultrashort pulse laser beam; the laser wavelength of the femtosecond laser is 750nm to 1100nm, the pulse width is 10fs to 900fs, the pulse energy is 10 muJ to 1mJ, the pulse repetition rate is 1KHz to 1MHz, and the laser beam quality M²Less than or equal to 1.5. Because the femtosecond laser has extremely short duration and small thermal stress, the subsurface damage and the microscopic defect of the workpiece to be processed can be reduced.

The laser tuning module is used for adjusting the working wavelength of laser, realizing high-transmittance laser output of a workpiece to be machined, facilitating the laser to be machined in the workpiece to be machined and avoiding the surface pollution of the workpiece to be machined. The laser tuning module is preferably an optical parametric amplifier, and the laser after tuning is difference frequency signal light with the wavelength ranging from 1300nm to 2000 nm.

The mechanical optical gate is used for controlling the rapid on-off of the laser transmission light path; the response time of the mechanical shutter is less than or equal to 1 ms.

The laser polarization module is used for adjusting the polarization states of the laser such as the polarization direction, the ellipsometry and the like, and avoiding the microscopic defect caused by the polarization state in the laser processing process; the laser polarization module is preferably a combination of a half-wave plate and a quarter-wave plate, with the half-wave plate placed in front of the quarter-wave plate.

The variable-power beam expander is used for continuously adjusting the diameter of a laser beam and is beneficial to effectively adjusting and controlling the filamentation length of the femtosecond laser; the maximum magnification of the variable power beam expander is in the range of 2X to 10X.

The plane mirror is used for adjusting a laser transmission light path to enable a light beam to vertically enter the optical diffraction element; the incidence angle of the plane mirror is 45 DEG + -5 deg.

The optical diffraction element is used for laser beam space shaping, realizes the output of a long-focal-depth uniformly-distributed beam, and is beneficial to the filamentation modification of femtosecond laser in the material; the optical diffraction element is preferably a cone lens with a cone angle in the range of 1 ° to 40 °. Traditional Gaussian beams are shaped into Bessel beams with longer focal depth through the cone lens, femtosecond laser is facilitated to form one section of millimeter-level light silk, the processing depth of laser single scanning is increased to 1mm from 10 mu m, and the processing efficiency is improved by 2 levels.

The filamentation modification module integrally reduces the shaped light beam according to a fixed proportion based on an optical imaging principle, enhances the laser power density to a hard and brittle material threshold value, and completes filamentation modification in the workpiece to be processed, wherein the laser filamentation modification can enhance the chemical reaction activity, greatly improve the chemical corrosion rate of a modification region, and realize the function of laser-induced chemical corrosion;

the filamentation modification module is preferably a micro-focusing system with the magnification of 5X-50X, which consists of a large-focus lens and a small-focus objective lens, wherein the focal length of the lens is in the range of 100mm to 500mm, the focal length of the objective lens is in the range of 10mm to 40mm, and the lens and the objective lens are coaxially arranged in a confocal point. The diameter of a light beam at a focus can be reduced integrally according to a fixed proportion for modification through the variable-power beam expander and the filamentation modification module, the laser forming processing precision is improved by 1 order of magnitude to 1 mu m, and the forming processing depth-diameter ratio is up to 1000.

The filamentation auxiliary part covers the surface of the workpiece to be processed, so that the femtosecond laser filamentation front end with unstable power density is prevented from acting on the workpiece to be processed, and the filamentation modification consistency of the workpiece to be processed is improved; the filamentation aid is preferably a double-sided polished fused silica plate having a thickness in the range of 0.3mm to 2mm and a diameter in the range of 15mm to 310 mm. The filamentation auxiliary part is covered on the workpiece to be processed, the laser filamentation front end with poor stability acts on the filamentation auxiliary part, and the filamentation middle end with good stability is used for the workpiece to be processed, so that the adverse effect of the workpiece to be processed caused by unstable power density of the filamentation front end is avoided, and the forming and processing consistency of the femtosecond laser is ensured.

The special clamping tool is used for fixing a workpiece to be machined, and the middle of the upper surface of the special clamping tool is hollowed to prevent high-power-density laser from damaging the tool; the size of the special clamping tool is within the range of 10mm to 300 mm.

The multi-axis linkage electric control displacement platform is used for three-dimensional complex path high-precision uniform motion; the multi-axis linkage electric control displacement platform is preferably a three-axis high-precision motion platform, the positioning precision of an X/Y axis is less than or equal to 10 mu m, and the stroke of a Z axis is more than or equal to 10 mm.

The industrial personal computer is used for cooperatively controlling the mechanical optical gate and the multi-axis linkage electric control displacement table to complete laser processing of the complex component;

the mechanical arm is used for moving the workpiece to be processed into the chemical corrosion tank after the laser processing is finished and moving the workpiece to be processed into the alkaline neutralization tank after the chemical corrosion is finished;

the chemical corrosion tank is composed of HF acid solution and matched with a filamentation modification module to finish the removal of materials by the femtosecond laser filamentation modification region through chemical corrosion, thereby achieving the purpose of precise molding of the complex component made of the hard and brittle materials; preferably, the HF solution concentration of the chemical etching pool is in the range of 1% to 30%, and the soaking time of the workpiece to be processed in the chemical etching pool is in the range of 1h to 120 h.

The alkaline neutralization tank is composed of NaOH alkaline solution and is used for neutralizing residual corrosive liquid of the workpiece to be processed after chemical corrosion is finished. Preferably, the concentration of the NaOH solution in the alkaline neutralization tank is in the range of 0.1% to 10%, and the soaking time of the workpiece to be processed in the alkaline neutralization tank is in the range of 0.1h to 1 h.

The invention discloses a system which integrates three functional areas of a special clamping tool, a chemical etching pool and an alkaline neutralizing pool into a whole, and realizes full-automatic operation of three procedures of laser filamentation modification, acid liquor corrosion forming and alkaline liquor neutralization cleaning by loading, unloading and transferring a workpiece to be processed through a mechanical arm, and the operation is convenient and simple.

The following examples of the present invention are given:

according to the embodiment of the invention, a femtosecond laser precision forming system for a complex component made of hard and brittle materials based on filamentation modification and chemical corrosion is shown in figure 1. The hard and brittle material complex component femtosecond laser precision forming processing system based on filamentation modification and chemical corrosion comprises: the device comprises a femtosecond laser 101, a laser tuning module 102, a mechanical shutter 103, a laser polarization module 104, a variable-magnification beam expander 105, a plane mirror 106, an optical diffraction element 107, a filamentation modification module 108, a filamentation auxiliary part 109, a clamping special tool 111, a multi-axis linkage electric control displacement table 112, an industrial personal computer 113, a mechanical arm 114, a chemical corrosion tank 115 and an alkaline neutralization tank 116.

The laser wavelength of the femtosecond laser is 1064nm, the pulse width is 300fs, the pulse energy is 100 muJ, the pulse repetition rate is 100KHz, and the laser beam quality M²Less than or equal to 1.1. Because the femtosecond laser output by the femtosecond laser has extremely short duration and small thermal stress, the subsurface damage and the microscopic defects can be reduced.

The laser tuning module is an optical parametric amplifier, and laser after tuning is difference frequency signal light with the wavelength of 1350 nm. Because the laser tuning module outputs the laser with high transmittance of the workpiece to be processed, the laser can be filamentized and modified in the material, and the surface pollution of the workpiece can be avoided.

The switching response time of the mechanical shutter is 0.1 ms.

The laser polarization module is a combination of a half-wave plate and a quarter-wave plate, and the half-wave plate is placed in front of the quarter-wave plate.

The maximum magnification of the variable power beam expander is 5X.

The incident angle of the plane mirror is 45 degrees.

The optical diffraction element is a cone lens with a cone angle of 30 °. Through the optics diffraction element with traditional gaussian beam shaping for the Bessel beam of longer depth of focus, be favorable to femto second laser to form one section millimeter magnitude light silk, increase laser single scanning processing degree of depth to 1mm by 10 mu m, machining efficiency promotes 2 orders of magnitude.

The filamentation modification module is a micro-focusing system with the magnification of 10X, which consists of a large-focus lens and a small-focus objective lens, wherein the focal length of the lens is 200mm, the focal length of the objective lens is 20mm, and the lens and the objective lens are coaxially arranged in a confocal point. The diameter of a light beam at a focus can be reduced integrally according to a fixed proportion for modification through the variable power beam expander and the filamentation modification module, the laser forming processing precision is improved by 1 order of magnitude to 1 mu m, and the forming processing depth-diameter ratio is up to 1000.

The filamentation auxiliary part is a double-sided polished fused quartz plate, the thickness of the filamentation auxiliary part is 0.5mm, and the diameter of the filamentation auxiliary part is 100 mm. The filamentation auxiliary part covers the workpiece to be processed, the laser filamentation front end with poor stability acts on the filamentation auxiliary part, the filamentation middle end with good stability is used for the workpiece to be processed, adverse effects of the workpiece to be processed caused by unstable power density of the filamentation front end are avoided, and the femtosecond laser forming processing consistency is ensured.

The size of the special clamping tool is 95 mm.

The multi-axis linkage electric control displacement platform is a three-axis high-precision motion platform, the positioning precision of an X/Y axis is less than or equal to 1 mu m, and the stroke of a Z axis is more than or equal to 20 mm.

The concentration of the HF solution in the chemical corrosion tank is 20%, and the soaking time of the workpiece to be processed in the chemical corrosion tank is 24 hours.

The concentration of the NaOH solution in the alkaline neutralization tank is 5%, and the soaking time of the workpiece to be processed in the alkaline neutralization tank is 0.5 h. The system integrates three functional areas of a special clamping tool, a chemical etching pool and an alkaline neutralizing pool, the workpiece to be processed is loaded, unloaded and transferred through the mechanical arm, the three procedures of laser filamentation modification, acid liquor corrosion forming and alkaline liquor neutralization cleaning are fully automatically operated, and the operation is convenient and simple.

According to the embodiment of the invention, the working process of the femtosecond laser precision forming processing system of the complex component of the hard and brittle material based on filamentation modification and chemical corrosion comprises the following steps:

the femtosecond laser 101 is started to output a femtosecond laser pulse beam with the wavelength of 1064nm, and then the laser wavelength of the femtosecond laser is adjusted to 1350nm through the laser tuning module 102. The laser transmission light path is controlled to be rapidly switched on and off by a mechanical shutter 103. The polarization state of the laser light is adjusted to be circularly polarized by the laser polarization module 104.

The femtosecond laser adjusts the beam diameter through the variable power beam expander 105, which is beneficial to adjusting and controlling the filamentation length and diameter. The laser beam transmission path is adjusted by the plane mirror 106 so that the beam is vertically incident on the optical diffraction element 107. The optical diffraction element 107 is used for modulating the light intensity distribution of the laser space and outputting a long-focus deep light beam, thereby being beneficial to the filamentation modification of the femtosecond laser in the material. Then, the laser power density is enhanced through the filamentation modification module 108, filamentation modification is completed in the hard and brittle material, and the chemical corrosion rate of the modified region is greatly improved. The front end of the femtosecond laser filamentation is prevented from acting on the workpiece 110 to be processed by the filamentation auxiliary part 109, and the quality modification consistency of the filamentation to be processed is improved.

A workpiece 110 to be machined is fixed and fixed through a special clamping tool 111, and then three-dimensional complex-path high-precision uniform motion is completed through a multi-axis linkage electric control displacement table 112. The mechanical shutter 103 and the multi-axis linkage electric control displacement table 112 are controlled by the industrial personal computer assistant 113, and the laser processing of the complex component is completed.

The workpiece 110 to be processed is moved into a chemical etching pool 115 by a mechanical arm 114, and the femtosecond laser filamentation modification region chemical etching is carried out to remove materials. After being soaked in a chemical corrosion tank consisting of 20% HF acid solution for 24 hours, the workpiece 110 to be processed is moved into an alkaline neutralization tank 116 by a mechanical arm 114, and residual corrosive liquid of the workpiece 110 to be processed is neutralized. Soaking the hard and brittle material in an alkaline neutralization tank consisting of 5% NaOH alkaline solution for 0.5h, and taking out the hard and brittle material by a mechanical arm 114 to finish the precise forming processing of the hard and brittle material complex component.

The system outputs the femtosecond laser with small thermal stress and high transmittance through the femtosecond laser and the laser tuning module, and the workpiece to be processed has no sub-surface damage, micro defects and surface pollution. According to the system, the traditional Gaussian beam is shaped into the Bessel beam with millimeter-order focal depth through the optical diffraction element, the laser single-scanning processing depth is increased to 1mm, and the processing efficiency is improved by 2 orders of magnitude. The system can wholly reduce the diameter of the light beam at the focus by 10 times through the variable power beam expander and the filamentation modification module for modifying, the laser forming processing precision is improved to 1 mu m, and the forming processing depth-diameter ratio is up to 1000. According to the system, the filamentation auxiliary part is covered on the workpiece to be processed, the front end of the laser filamentation with poor stability acts on the filamentation auxiliary part, the middle end of the filamentation with good stability is used for the workpiece to be processed, and the femtosecond laser forming processing consistency is good. The system integrates three functional areas of a special clamping tool, a chemical etching pool and an alkaline neutralizing pool, and workpieces to be processed are loaded, unloaded and transferred through the mechanical arm, so that the full-automatic operation of three procedures of laser filamentation modification, acid liquor corrosion forming and alkaline liquor neutralization cleaning is realized, and the operation process of personnel is simplified.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that those skilled in the art can change, modify, replace and modify the above embodiments within the scope of the present invention, and fall into the protection scope of the present invention.