A device for imprinting mechanical properties of hard and brittle materials assisted by acoustic-thermal compound energy field

Abstract

The present application relates to a kind of sound heat composite energy field assisted hard brittle material mechanical property imprint test device, belong to hard brittle material mechanical property imprint test and ultra-precision machining field.Ultrasonic vibration module, imprint movement module, laser irradiation module and displacement force measuring module are respectively installed on support adjusting module.The present application has the advantages of novel compact structure, stable performance, accurate operation and flexible operation, not only can be used to test the critical condition of ductile brittle transition and mechanical performance index of hard brittle material under the action of ultrasonic vibration or laser irradiation single energy field, but also can characterize the mechanism of action and influence law of ultrasonic vibration and laser irradiation composite energy field and its process parameters on the ductile brittle transition and mechanical cutting performance of hard brittle material, and the acoustic-thermal coupling effect between ultrasonic vibration and laser irradiation and its influence.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of mechanical property imprint testing of hard and brittle materials under the condition of ultrasonic and laser assistance and ultra-precision machining, and particularly relates to a device for mechanical property imprint testing of hard and brittle materials under the assistance of an acoustic-thermal composite energy field. BACKGROUND

[0002] At present, hard and brittle materials such as monocrystalline germanium, tungsten carbide, fused quartz and ceramic matrix composite materials are widely used in many important fields such as optical electronics, aerospace, precision manufacturing and semiconductors due to their unique and excellent physical and mechanical properties. For example, ceramic matrix silicon carbide composite materials are widely used in various harsh working environments of high temperature and high pressure, such as missile nose cones or antenna covers, engine nozzles, aircraft brake pads, etc., because of their excellent strength ratio, heat resistance, oxidation resistance and corrosion resistance. Monocrystalline germanium is used for various infrared optical windows because it has good penetration to specific infrared wavebands. However, hard and brittle materials are prone to cracks, holes, high-pressure phase changes and residual stress surface and subsurface damage and defects when processed by traditional mechanical cutting methods due to their brittleness, high hardness, poor thermal conductivity and low fracture toughness, and are accompanied by serious tool wear, high cutting force and temperature, and low material removal efficiency, which seriously restricts the application and development of various high-performance hard and brittle materials and their machining technology. Therefore, energy field assisted machining technologies such as ultrafast laser and ultrasonic vibration are widely used to improve the comprehensive performance of traditional mechanical cutting methods, which can effectively improve the critical cutting depth of hard and brittle materials, reduce cutting force / temperature, reduce tool wear, enhance material removal efficiency and suppress surface and subsurface damage or defects, and ultimately achieve high-quality, high-efficiency and high-precision machining of various high-performance hard and brittle materials or difficult-to-machine materials.

[0003] However, in order to ensure the surface quality, shape accuracy and removal efficiency of hard and brittle materials during cutting, it is usually necessary to determine their physical and chemical properties and mechanical properties under the combined action of ultrasonic vibration and pulsed laser (acoustic-thermal complex energy field) through experimental means before cutting. Therefore, there is an urgent need for an acoustic-thermal complex energy field assisted imprint device for testing the physical and chemical properties and mechanical properties of hard and brittle materials. At present, scholars at home and abroad have carried out in-depth research on the imprint test method and device of material mechanical properties assisted by ultrasonic vibration or laser irradiation single energy field. For laser-assisted indentation and scratch test devices, Xu Jianfeng et al. of Huazhong University of Science and Technology proposed a laser in-situ assisted indentation and scratch device (CN114918530A) to characterize the material removal mechanism and mechanical properties of hard and brittle materials under the action of laser assistance by combining laser processing technology with micron indentation / scratch testing. Shi Guangfeng et al. of Changchun University of Science and Technology also proposed a method and device for laser in-situ assisted grinding of single crystal diamond conical indenter (CN116100397A) to solve the problems of corners, blunt circular notches and irregularities on the conical surface of the single crystal diamond conical indenter after grinding. For ultrasonic vibration assisted indentation and scratch test devices, Li Yuggang et al. of Shanghai Jiaotong University proposed an ultrasonic assisted indentation tester with simple structure, convenient operation, high test precision, low maintenance cost and instrument (CN109738315A), which can realize indentation test under the superimposed state of ultrasonic vibration load and static indentation load. Jiang Chen et al. of Shanghai University of Science and Technology also proposed an ultrasonic vibration indentation experiment damping device (CN104833568B) which can accurately control the indentation load for optical glass.

[0004] In summary, the existing indentation and scratch test devices can only test the physical and chemical properties and mechanical properties of hard and brittle materials under the action of laser irradiation or ultrasonic vibration single energy field. However, there are few reports on indentation / scratch test methods and devices under the action of acoustic-thermal complex energy field. Therefore, it is difficult to effectively characterize the material removal mechanism and mechanical property change rule of hard and brittle materials under the action of acoustic-thermal complex energy field. In addition, the existing indentation test devices generally have many shortcomings such as small static and dynamic load, inflexible parameter adjustment, non-decoupled acoustic-thermal energy field, redundant structure, unsatisfactory test precision and so on. For example, the related laser-assisted indentation and scratch test devices have space and time lag between the laser irradiation area and the imprint forming area on the material surface, and the ultrasonic vibration indentation / scratch test devices also do not consider the force and motion coupling between the loading and unloading and the ultrasonic vibration excitation load, which worsens the test precision of the material physical and chemical properties and mechanical properties. SUMMARY

[0005] The application provides a kind of acoustic-thermal composite energy field assisted hard and brittle material mechanical property imprinting test device to solve the problems of indentation and scratch test device, such as small static and dynamic load, inflexible parameter control, undecoupled acoustic-thermal energy field, redundant structure, unsatisfactory test precision, spatial and temporal lag between laser irradiation area and imprint forming area, etc.

[0006] The technical scheme adopted by the application is to include a support adjustment module, an ultrasonic vibration module, an imprinting motion module, a laser irradiation module and a displacement force measurement module, wherein the ultrasonic horn in the ultrasonic vibration module is coaxially placed in the stepped through hole of the gantry mounting cross beam in the support adjustment module through the flange structure in the middle, and then clamped and fixed by the ultrasonic horn flange cover plate and six flange cover plate fastening bolts; the mirror group packaging box in the imprinting motion module is fixedly connected with the mirror seat bottom plate by the precise dynamometer fixed block screw in the displacement force measurement module; the two-dimensional manual Z-axis translation stage in the laser irradiation module is installed and fixed on the laser displacement stage base of the support adjustment module by the translation stage fixing screw; and the miniature electric lifting platform in the displacement force measurement module is connected and fixed with the electric lifting platform base arranged on the base plate of the support adjustment module by four miniature electric lifting platform fastening bolts.

[0007] The support adjustment module includes a gantry mounting cross beam, a base plate, gantry columns, a laser displacement stage base, an electric lifting platform base, translation stage fixing screws, column base plate fastening bolts and electric lifting platform fixing studs, wherein the laser displacement stage base and the electric lifting platform mounting base are connected and installed with the base plate by multiple groups of translation stage fixing screws, column base plate fastening bolts and electric lifting platform fixing studs, and the gantry mounting cross beam is fixedly connected with the two gantry columns by cross beam column fixing bolts.

[0008] The ultrasonic vibration module includes an ultrasonic transducer, an ultrasonic horn, an ultrasonic horn flange cover plate, a sample mounting clamp, a fixed bolt, a clamp transducer fixing bolt, a flange cover plate fastening bolt, a cross beam and column fixing stud, a lock washer, a cross beam nut and a sample clamping stud, wherein the fixed bolt passes through the through hole of the ultrasonic transducer and is connected with the threaded hole at the tail of the ultrasonic horn, the sample mounting clamp is connected with the threaded hole at the head of the ultrasonic horn by the fastening bolt, and the test sample is positioned and clamped by the clamping stud and the sample mounting clamp; the ultrasonic horn is coaxially placed in the stepped through hole of the gantry mounting cross beam through the flange structure in the middle, and then fastened in the stepped through hole of the gantry mounting cross beam by the ultrasonic horn flange cover plate and six flange cover plate fastening bolts.

[0009] The embossing motion module comprises a mirror group packaging box, a mirror base, a mirror, a circular cross-section rubber ring, a focusing lens, a square lower wedge plate, a circular upper wedge plate, a single degree of freedom flexible mechanism, a ring-shaped piezoelectric stack, a diamond indenter, a mirror adjusting bolt, a focusing lens X-axis fine adjustment stud, a square cross-section rubber ring, a diamond indenter locking bolt, a locking nut, a wedge pre-tightening bolt, a focusing lens Y-axis fine adjustment stud, a mirror base and flexible mechanism fastening bolt, a cylindrical rubber plug and a mirror fastening screw, wherein the mirror group packaging box is fixedly connected to the precision dynamometer through a mirror base bottom plate and a fixed connection pad bolt, the mirror is placed in a circular groove in the bottom of the mirror base and is fixed by using a fastening bolt and a rubber plug; the mirror base is fixedly connected to the mirror base bottom plate by using a mirror base bottom plate fastening bolt; the mirror group packaging box and the single degree of freedom flexible mechanism are connected and fixed by using four fastening bolts, and a sandwich structure is formed by sequentially placing a circular cross-section rubber ring, a laser focusing lens and a square cross-section rubber ring in an axial space formed by the stepped through holes of the four fastening bolts from bottom to top, and the circular cross-section rubber ring is directly extruded by four focusing lens X-axis fine adjustment studs and focusing lens Y-axis fine adjustment studs; the square lower wedge plate is placed in the first stage of the single degree of freedom flexible mechanism, and at the same time, the circular upper wedge plate is placed in the groove of the square lower wedge plate; the ring-shaped piezoelectric stack and the diamond indenter are sequentially placed into the axial tapered hole at the top of the single degree of freedom flexible mechanism, the front and back ends of the ring-shaped piezoelectric stack act on the bottom of the diamond indenter and the plane of the circular upper wedge plate, respectively, and the diamond indenter is clamped and fixed by using a diamond indenter locking bolt and a locking nut; the square lower wedge plate is pushed to move along the X-axis in the square groove at the bottom of the flexible mechanism by using a pre-tightening bolt acting on the square lower wedge plate, indirectly driving the circular upper wedge plate to move along the Z-axis in the circular hole in the middle of the flexible mechanism, realizing axial pre-tightening of the ring-shaped piezoelectric stack, and the upper and lower wedge plates, the piezoelectric stack and the diamond indenter all adopt a hollow structure to avoid blocking the light path.

[0010] The laser irradiation module comprises a pulse laser, a laser base mounting table, a laser base, a two-dimensional manual X-axis translation table, a two-dimensional manual Z-axis translation table, a laser front-end Z-axis pose adjustment bolt, a laser rear-end Z-axis pose adjustment bolt, a laser front-end X-axis pose adjustment bolt, a laser rear-end X-axis pose adjustment bolt, a rubber protection ring, a two-dimensional displacement table Z-axis adjustment rod, a two-dimensional displacement table X-axis adjustment rod, a laser positioning bolt, a laser fastening bolt and a laser base mounting table fastening bolt, wherein two rubber rings are sleeved on the front and rear ends of the laser respectively; the laser is coaxially arranged in the through hole of the mounting base, the laser front-end Z-axis pose adjustment bolt, the laser rear-end Z-axis pose adjustment bolt, the laser front-end X-axis pose adjustment bolt and the laser rear-end X-axis pose adjustment bolt are screwed into the mounting base, the laser mounting base is fixedly connected with the laser base mounting table through the fastening bolt, and the laser base mounting table is fixedly connected with the Z-axis translation table of the two-dimensional manual displacement table through the laser base mounting table fastening bolt; the two-dimensional manual X-axis translation table, the two-dimensional manual Z-axis translation table, the two-dimensional displacement table Z-axis adjustment rod and the two-dimensional displacement table X-axis adjustment rod are assembled and fixed on the laser displacement table base by using the translation table fixing screw.

[0011] The displacement force measurement module comprises a miniature electric lifting platform, a force gauge mounting seat, a precision force gauge and a mirror seat bottom plate, a mirror seat bottom plate fastening bolt, a force gauge fastening bolt, a force gauge mounting bottom plate fastening bolt and a miniature electric lifting platform fastening bolt, wherein the miniature electric lifting platform is fixedly connected with the electric lifting platform base arranged on the base plate through four miniature electric lifting platform fastening bolts, the force gauge mounting seat is connected and mounted with the miniature electric lifting platform through four force gauge mounting bottom plate fastening bolts, the precision force gauge is fixedly connected with the mounting base thereof through four force gauge fastening bolts, and the mirror seat bottom plate is fixedly mounted after being reversely penetrated through the precision force gauge through four mirror seat bottom plate fastening bolts.

[0012] The device comprises a laser irradiation module, an ultrasonic vibration module, a imprinting motion module, a displacement force measurement module and a support adjustment module. The laser light path is shaped, centered and focused by using a fiber laser, a laser collimator, a mirror and a focusing lens and corresponding coarse and fine adjustment mechanisms, so that the laser spot penetrates the diamond indenter along the axial direction and accurately acts on the imprinting forming area of the material to achieve the optimal laser enhancement efficiency. Meanwhile, the workpiece sample is made to produce high-frequency vibration along the imprinting axis by an ultrasonic transducer and an ultrasonic amplitude transformer, and the diamond indenter is made to move along the imprinting axis for loading and unloading by a ring-shaped piezoelectric stack directly driving a single-degree-of-freedom flexible mechanism, so as to realize the force / motion superposition of the ultrasonic vibration load and the static / quasi-static imprinting load. This mode has the advantages of simple structure, easy operation, low cost and the ability to realize coarse and fine synchronous adjustment of the device.

[0013] The beneficial effects of the present application include:

[0014] 1. Compared with the traditional material mechanics performance single energy field assisted imprint test, the acoustic-thermal composite energy field assisted imprint test device of the present application can not only be used for testing the critical conditions and mechanical properties of the ductile-brittle transition of hard and brittle materials under the action of ultrasonic vibration or laser irradiation single energy field, but also can study the critical conditions and mechanical properties of the ductile-brittle transition under the combined action of ultrasonic vibration and laser irradiation composite energy field, and the action mechanism and influence law of the acoustic-thermal coupling effect between ultrasonic vibration and laser irradiation on material properties.

[0015] 2. The present application can be used to characterize the influence law of acoustic-thermal single energy field or composite energy field on the mechanical properties such as yield strength, tensile strength and elongation of hard and brittle materials, and the subsurface / surface quality such as residual stress, tool wear and crack damage, thereby effectively evaluating and accurately predicting the mechanical cutting performance (including surface quality, tool wear, residual stress, cutting force / heat and material removal efficiency, etc.) of laser irradiation-ultrasonic vibration assisted machining of various hard and brittle materials, and providing necessary reference for process parameter optimization and system structure improvement of laser irradiation-ultrasonic vibration assisted machining process.

[0016] 3. The imprint motion module of the present application adopts the combination form of micro-displacement lifting platform and piezoelectric actuated single degree of freedom flexible mechanism in coarse and fine series, which takes into account the advantages of large stroke of micro-displacement platform and high precision of flexible mechanism. Among them, the electric lifting platform is used to adjust the relative position between the diamond indenter and the specimen sample in a larger motion range, effectively solving the adverse effects of specimen size difference and system assembly error, and the piezoelectric actuated single degree of freedom flexible mechanism is used to realize the precise control of force and motion in the loading-unloading process of imprint forming, which has the advantages of high control precision and good dynamic performance.

[0017] 4. The light path regulation module of the present application adopts multi-level and multi-dimensional coarse and fine adjustment mechanism, which effectively improves the regulation precision and flexibility of the light path system. At the laser beam source, the collimating laser head is used for coarse adjustment of its horizontal and vertical position through a two-dimensional manual displacement platform, and fine adjustment of the center horizontal and vertical position of the laser, as well as the pitch and swing attitude through the laser installation base and the corresponding adjustment screws; in the middle process of the light path, the angles of the reflecting mirrors, the three-dimensional positions and horizontal attitude of the focusing lenses are fine adjusted through the adjustment screws; through the coarse and fine combined regulation mode, it can ensure that the laser spot accurately passes through the diamond indenter and directly irradiates the imprint forming area of the specimen and the indenter.

[0018] 5. Compared with the structural layout of the conventional device, the laser irradiation and ultrasonic vibration module of the device of the present application adopts a parallel configuration with compact structure and high stability, and uses a mirror to turn the laser beam in the horizontal direction by 90° to the vertical direction, effectively reducing the overall size of the device along the axial direction, enhancing the compactness and stability of the system structure, and making the light path adjustment more flexible and the installation and maintenance more convenient; the mirror realizes precise adjustment of the reflection angle of the light path by causing elastic deformation of the mounting base of the mirror through an adjusting bolt, and simultaneously uses a sandwich structure of "circular cross-section rubber ring-laser focusing lens-square cross-section rubber ring" to realize precise adjustment of the axial position and horizontal inclination angle of the laser focusing lens by using the stress deformation and elastic recovery force of the upper and lower rubber rings, having the advantages of flexible and simple focusing distance control, high focusing and centering precision, and simple and compact structure. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic diagram of the present application;

[0020] Figure 2 is a rear view of the present application;

[0021] Figure 3 is a structural schematic diagram of the support adjustment module of the present application;

[0022] Figure 4 is a structural schematic diagram of the ultrasonic vibration module of the present application;

[0023] Figure 5 is an assembly drawing of the imprinting motion module of the present application;

[0024] Figure 6 is a structural schematic diagram of the imprinting motion module of the present application;

[0025] Figure 7 is an A-A sectional view of Figure 6 ;

[0026] Figure 8 is a left view of Figure 6 ;

[0027] Figure 9 is a B-B sectional view of Figure 8 ;

[0028] Figure 10 is a structural schematic diagram of the laser irradiation module of the present application;

[0029] Figure 11 is a structural schematic diagram of the displacement force measurement module of the present application;

[0030] Figure 12 is a structural schematic diagram of the mirror group packaging box of the present application;

[0031] Figure 13Fig. 1 is a structural schematic view of a sample mounting clamp and a sample of the present application;

[0032] Figure 14 Fig. 2 is a bottom view of the sample mounting clamp and the sample of the present application;

[0033] Figure 15 Fig. 3 is a structural schematic view of a single degree of freedom flexible mechanism of the present application;

[0034] The reference signs are as follows:

[0035] 1-support adjustment module, 2-ultrasonic vibration module, 3-embossing motion module, 4-laser irradiation module, 5-displacement force measurement module, 6-test sample; 101-gantry mounting beam, 102-base plate, 103-gantry column, 104-laser displacement stage base, 105-electric lifting stage base, 106-translational stage fixing screw (8), 107-column-base plate fastening bolt (8), 108-electric lifting stage fixing stud; 201-ultrasonic transducer, 202-ultrasonic amplitude transformer, 203-ultrasonic amplitude transformer flange cover plate, 204-sample mounting clamp, 205-fixing bolt, 206-clamp-transducer fastening bolt, 207-flange cover plate fastening bolt (6), 208-beam-column fixing stud (8), 209-loose piece pad (8), 210-beam nut (8), 211-sample clamping stud; mirror group packaging box 301, mirror base 302, mirror 303, circular cross-section rubber ring 304, focusing lens 305, square lower wedge plate 306, circular upper wedge plate 307, single degree of freedom flexible mechanism 308, ring-shaped piezoelectric stack 309, diamond indenter 310, mirror adjusting bolt 311, focusing lens X-axis fine adjustment stud 312, square cross-section rubber ring 313, diamond indenter locking bolt 314, locking nut 315, wedge pre-tightening bolt 316, focusing lens Y-axis fine adjustment stud 317, mirror base-flexible mechanism fastening bolt 318, cylindrical rubber plug 319 and mirror fastening screw 320; 401-pulse laser, 402-laser base mounting stage, 403-laser base, 404-two-dimensional manual X-axis translational stage, 405-two-dimensional manual Z-axis translational stage, 406-laser front-end Z-axis pose adjustment bolt (2), 407-laser rear-end Z-axis pose adjustment bolt (2), 408-laser front-end X-axis pose adjustment bolt (2), 409-laser rear-end X-axis pose adjustment bolt (2), 410-rubber protection ring (2), 411-two-dimensional displacement stage Z-axis adjustment rod, 412-two-dimensional displacement stage X-axis adjustment rod, 413-laser positioning bolt, 414-laser fastening bolt (2), 415-laser base mounting stage fastening bolt (8), 501-micro electric lifting stage, 502-force gauge mounting base plate, 503-precision force gauge, 504-mirror base plate, 505-mirror base plate fastening bolt (4), 506-force gauge fastening bolt (8), 507-force gauge mounting base plate fastening bolt (4), 508-micro electric lifting stage fastening bolt (4). DETAILED DESCRIPTION

[0036] To make the objectives, solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. The following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0037] like Figure 1 , 2 As shown, the system includes a support adjustment module 1, an ultrasonic vibration module 2, an imprinting motion module 3, a laser irradiation module 4, and a displacement force measurement module 5. In the ultrasonic vibration module 2, the ultrasonic amplitude transformer 202 is coaxially placed within the stepped through-hole of the gantry mounting beam 101 in the support adjustment module 1 via a central flange structure, and then clamped and fixed using the ultrasonic amplitude transformer flange cover plate 203 and six flange cover plate fastening bolts 207. In the imprinting motion module 3, the mirror assembly packaging box 301 is fixed to the mirror base plate 504 via precision force measuring instrument fixing pad screws 505 in the displacement force measurement module 5. In the laser irradiation module 4, the two-dimensional manual Z-axis translation stage 404 is mounted and fixed to the laser displacement stage base 104 of the support adjustment module 1 using translation stage fixing screws. In the displacement force measurement module 5, the miniature electric lifting stage 501 is connected and fixed to the electric lifting stage base 105 arranged on the base plate 102 of the support adjustment module 1 via four miniature electric lifting stage fastening bolts 508.

[0038] like Figure 2 , 3 As shown, the support adjustment module 1 includes a gantry mounting beam 101, a base plate 102, gantry columns 103, a laser displacement stage base 104, an electric lifting stage base 105, translation stage fixing screws 106, column base plate fastening bolts 107, and electric lifting stage fixing studs 108. The laser displacement stage base 104, the electric lifting stage mounting base 105, and the two gantry columns 103 are respectively connected and installed to the base plate 102 through multiple sets of translation stage fixing screws 106, column base plate fastening bolts 107, and electric lifting stage fixing studs 108. The gantry mounting beam 101 is fixedly connected to the two gantry columns 103 through beam column fixing bolts 208.

[0039] like Figure 2 , 4As shown in Figures 13 and 14, the ultrasonic vibration module 2 includes an ultrasonic transducer 201, an ultrasonic amplitude transformer 202, an ultrasonic amplitude transformer flange cover 203, a sample mounting fixture 204, a connecting bolt 205, a fixture transducer set bolt 206, a flange cover fastening bolt 207, a beam and column fixing stud 208, an anti-loosening washer 209, a beam nut 210, and a sample clamping stud 211. The connecting stud 205 passes through the through hole of the ultrasonic transducer 201 and is connected to the ultrasonic amplitude transformer 202. The threaded holes at the tail end are connected, and the sample mounting fixture 204 is connected to the threaded hole at the head of the ultrasonic amplitude transformer 202 by fastening bolts 206. The test sample 6 is positioned and clamped by clamping bolts 211 and sample mounting fixture 204. The ultrasonic amplitude transformer 202 is placed coaxially in the stepped through hole of the gantry mounting beam 101 through the flange structure in the middle, and then fastened in the stepped through hole of the gantry mounting beam 101 by the ultrasonic amplitude transformer flange cover plate 203 and six flange cover fastening bolts 207.

[0040] like Figure 2 , 5, 6, 7, 8, 9, 12, 15, the embossing movement module 3 includes mirror group packaging box 301, mirror base 302, mirror 303, circular cross-section rubber ring 304, focusing lens 305, square lower wedge plate 306, circular upper wedge plate 307, single degree of freedom flexible mechanism 308, annular piezoelectric stack 309, diamond indenter 310, mirror adjusting bolt 311, focusing lens X-axis fine adjustment stud 312, square cross-section rubber ring 313, diamond indenter locking bolt 314, locking nut 315, wedge pre-tightening bolt 316, focusing lens Y-axis fine adjustment stud 317, mirror seat and flexible mechanism fastening bolt 318, cylindrical rubber plug 319 and mirror fastening screw 320, wherein the mirror group packaging box 301 is fixedly connected with the precision dynamometer 503 through the mirror seat bottom plate 504 and fixedly connected with the block screw 505, the mirror 303 is placed in the circular groove of the mirror base 302 and is fixed by using the fastening bolt 320 and the rubber round plug 319; the mirror base 302 is fixedly connected with the mirror seat bottom plate 504 by using the mirror seat bottom plate fastening bolt 505; the mirror group packaging box 301 and the single degree of freedom flexible mechanism 308 are connected and fixed by using four fastening bolts 318, and the circular cross-section rubber ring 304, the laser focusing lens 305 and the square cross-section rubber ring 313 are sequentially placed from bottom to top in the axial space formed by the stepped through holes to form a sandwich structure, and the circular cross-section rubber ring 304 is directly extruded by the four focusing lens X-axis fine adjustment studs 312 and the focusing lens Y-axis fine adjustment stud 317; the square lower wedge plate is placed in the first stage of the single degree of freedom flexible mechanism, at the same time, the circular upper wedge plate 307 is placed in the groove of the square lower wedge plate 306; the annular piezoelectric stack 309 and the diamond indenter 310 are sequentially placed into the axial tapered hole at the top of the single degree of freedom flexible mechanism 308, the front and back ends of the annular piezoelectric stack 309 act on the bottom of the diamond indenter 310 and the plane of the circular upper wedge plate 307, respectively, and the diamond indenter is clamped and fixed by using the diamond indenter locking bolt 314 and the locking nut 315; the square lower wedge plate 306 is pushed to move along the X-axis in the square groove at the bottom of the flexible mechanism 308 by the pre-tightening screw 316 acting on the square lower wedge plate 306, indirectly driving the circular upper wedge plate 307 to move along the Z-axis in the circular hole in the middle of the flexible mechanism, realizing the axial pre-tightening of the annular piezoelectric stack 309, and the upper and lower wedge plates, the piezoelectric stack and the diamond indenter all adopt a hollow structure to avoid blocking the light path.

[0041] As Figure 2 , 10As shown, the laser irradiation module 4 includes a pulsed laser 401, a laser base mounting table 402, a laser base 403, a two-dimensional manual X-axis translation table 404, a two-dimensional manual Z-axis translation table 405, a laser front-end Z-axis pose adjustment bolt 406, a laser rear-end Z-axis pose adjustment bolt 407, a laser front-end X-axis pose adjustment bolt 408, a laser rear-end X-axis pose adjustment bolt 409, a rubber protection ring 410, a two-dimensional displacement table Z-axis adjustment rod 411, a two-dimensional displacement table X-axis adjustment rod 412, a laser positioning bolt 413, a laser fastening bolt 414, and a laser base mounting table fastening bolt 415, wherein the front and rear ends of the laser 401 are respectively sleeved with two sections of rubber rings 410; the laser 401 is coaxially arranged in the through hole of the mounting base 403, the laser front-end Z-axis pose adjustment bolt 406, the laser rear-end Z-axis pose adjustment bolt 407, the laser front-end X-axis pose adjustment bolt 408, and the laser rear-end X-axis pose adjustment bolt 409 are screwed into the mounting base, the laser mounting base 403 is fixedly connected with the laser base mounting table 402 through the fastening bolt 413, and the laser base mounting table 402 is fixedly connected with the two-dimensional manual displacement table Z-axis translation table 405 through the laser base mounting table fastening bolt 415; the two-dimensional manual X-axis translation table 404, the two-dimensional manual Z-axis translation table 405, the two-dimensional displacement table Z-axis adjustment rod 411, and the two-dimensional displacement table X-axis adjustment rod 412 are assembled and fixed on the laser displacement table base 104 by using the translation table fixing screw 106.

[0042] As shown in Figure 2 , 11 As shown, the displacement force measurement module 5 includes a miniature electric lifting table 501, a force gauge mounting seat 502, a precision force gauge 503, a mirror seat bottom plate 504, a mirror seat bottom plate fastening bolt 505, a force gauge fastening bolt 506, a force gauge mounting bottom plate fastening bolt 507, and a miniature electric lifting table fastening bolt 508, wherein the miniature electric lifting table 501 is fixedly connected with the electric lifting table base 105 arranged on the base plate 102 through four miniature electric lifting table fastening bolts 508, the force gauge mounting seat 502 is connected and installed with the miniature electric lifting table 501 by using four force gauge mounting bottom plate fastening bolts 507, the precision force gauge 503 is fixedly connected with its mounting seat 502 by using four force gauge fastening bolts 506, and the four mirror seat bottom plate fastening bolts 505 are reversely passed through the precision force gauge 503 and fixedly installed with the mirror seat bottom plate 504.

[0043] Working principle and operation process:

[0044] 1. The support and adjustment module 1 is used for the installation support and position adjustment of each main part or module, and can perform preliminary adjustments to the laser installation height, the spatial orientation and relative distance between the test sample 6 and the diamond indenter 310; the ultrasonic vibration module 2 uses the ultrasonic transducer 201 and the ultrasonic amplitude transformer 202 to apply high-frequency vibration with specific frequency, amplitude and mode to the test sample, and completes the positioning and clamping of the test sample 6; the imprinting motion module 3 includes a reflector 303, a reflector seat 301, a focusing lens 305 and a circular cross-section rubber ring 304 and a square cross-section rubber ring 313, which can calibrate, shape, reverse and focus the laser beam, so that the laser beam penetrates the diamond indenter 310 axially and then irradiates. The diamond indenter 310 acts on the surface of the sample under test, and directly drives the single-degree-of-freedom flexible mechanism 308 to generate a precise axial imprinting motion by using the annular piezoelectric stack 309 to imprint the sample surface. The laser irradiation module 4 is used for the coarse and fine adjustment and installation and fixation of the position and attitude of the laser 401, the emission, collimation and focusing of the pulsed laser, and the fastening installation of the laser. The miniature electric lifting platform 501 in the displacement force measurement module 5 is used to complete the precise adjustment of the initial position and relative distance between the test sample 6 and the diamond indenter 310, while the precision force measuring instrument 503 is used to measure and record the changes in imprinting force and displacement during the loading and unloading process of material imprinting in real time.

[0045] 2. The experimental sample 6 is clamped in the fixture 204 at the end of the ultrasonic amplitude transformer 202. The experimental sample is positioned and clamped using clamping bolts and the V-shaped structure of the sample mounting fixture. This method has the advantages of compact and lightweight structure, simple positioning and clamping, and variable sample size. The height of the gantry beam 101 is initially adjusted according to the axial dimension of the experimental prototype. After determining the position, the studs 208 are used for fastening. The ends of the studs are locked and fixed using anti-loosening washers 209 and beam nuts 210 to avoid damage to the gantry column adjustment. The micro electric lifting platform 501 is adjusted so that the relative distance between the diamond indenter 310 and the experimental sample 6 is within the working range of the single-degree-of-freedom flexible mechanism 308. The electric lifting platform 501 enables a wide range of adjustment of the relative position between the diamond indenter and the sample, solving the adverse effects of sample size differences and system assembly errors.

[0046] 3. Open the precision dynamometer 503 and related software; the center position of the laser 401 along the X-axis and Z-axis can be coarsely adjusted by manually rotating the Z-axis adjustment rod 411 and the X-axis adjustment rod 412 of the two-dimensional displacement table; open the laser, emit a Gaussian laser, and use the Z-axis pose adjustment screw 406 at the front end of the laser, the Z-axis pose adjustment screw 407 at the rear end of the laser to finely adjust the Z-direction position and the pitch angle in the YZ plane of the laser 401, and use the X-axis pose adjustment screw 408 at the front end of the laser and the X-axis pose adjustment screw 409 at the rear end of the laser to finely adjust the X-direction position and the roll angle in the XY plane of the laser 401. The laser is protected by two rubber protection rings 410 to prevent the laser from being squeezed and deformed or damaged by the Z-axis pose adjustment screw 406 at the front end of the laser, the Z-axis pose adjustment screw 407 at the rear end of the laser, the X-axis pose adjustment screw 408 at the front end of the laser, and the X-axis pose adjustment screw 409 at the rear end of the laser, and can achieve a certain elastic recovery after fine adjustment and has a certain ability to isolate external environmental vibration; the laser is directed to the reflector 303, and the elastic deformation of the reflector base 302 caused by the adjustment screw 311 is used to finely adjust the angle of the reflector, realize the 90° turning of the laser light path, and has the advantages of compact and stable structure and quick and flexible adjustment; after the position and attitude of the laser are finely adjusted, the laser positioning screw 413 and the laser fastening screw 414 are used to complete the positioning and fixing of the laser 401 and its mounting base 403; after the adjustment is completed, the locking mechanism of the translation table is tightened to fix the laser; the circular rubber ring 304 is directly squeezed by the X-axis fine adjustment screw 312 and the Y-axis fine adjustment screw 317 of the focusing lens, which protects the laser focusing lens 305 while indirectly pushing it to produce axial micro-displacement, and realizes the precise adjustment of the axial focal length and horizontal attitude of the focusing lens 305 under the joint action of the elastic recovery force of the upper and lower circular cross-section rubber rings 304 and the square cross-section rubber ring 313. The circular cross-section rubber ring 304 and the square cross-section rubber ring 313 also have the functions of protection and vibration isolation for the focusing lens, and finally ensure that the laser beam accurately passes through the diamond indenter and then directly irradiates the surface imprinting forming area of the test piece; finally, the laser beam passes through the reflector 303 and the focusing lens 305 after reflection and focusing, and then passes through the diamond indenter 310 to irradiate the imprinting forming area. This method has the advantages of flexible focal length control, accurate focusing centering, and simple and compact structure.

[0047] 4. Turn the wedge pre-tightening bolt 316 to push the square lower wedge plate 306 to move in the X-axis direction in the square slot at the bottom of the single degree of freedom flexible mechanism 308, indirectly drive the circular upper wedge plate 307 to move in the Z-axis direction in the circular hole in the middle of the single degree of freedom flexible mechanism, realize the pre-tightening of the annular piezoelectric stack 309, and the upper and lower wedge plates, piezoelectric stack and diamond indenter all adopt a hollow structure to avoid blocking the light path; turn on the ultrasonic transducer 201 to drive the sample to produce high-frequency vibration of a specific frequency, amplitude and vibration mode, use the annular piezoelectric stack driver 309 to directly push the single degree of freedom flexible mechanism to produce elastic deformation, so that the diamond indenter moves in the axial direction for loading and unloading, and the required imprint forming motion in the test process is obtained; the piezoelectric actuated single degree of freedom flexible mechanism can complete the precise regulation and control of the loading and unloading load / motion in the imprint forming process, and has the advantages of high control precision and good dynamic performance.

[0048] 5. Record the experimental data, after the completion of the imprinting, turn off the laser, ultrasonic generator, force sensor and annular piezoelectric stack, take out the test sample from the workpiece clamp, and the experiment is ended.

Claims

1. A device for imprint testing of the mechanical properties of hard and brittle materials assisted by a combined acoustic and thermal energy field, characterized in that: The module comprises a support adjustment module, an ultrasonic vibration module, a pressure imprinting motion module, a laser irradiation module and a displacement force measurement module, wherein the ultrasonic horn in the ultrasonic vibration module is coaxially placed in the stepped through hole of the crossbeam of the support adjustment module through the flange structure in the middle, and is clamped and fixed by the ultrasonic horn flange cover plate and six flange cover plate fastening bolts, the mirror group packaging box in the pressure imprinting motion module is fixedly connected with the mirror seat bottom plate through the precise force gauge fixed connection pad bolt in the displacement force measurement module, the two-dimensional manual Z-axis translation stage in the laser irradiation module is installed and fixed on the laser displacement stage base of the support adjustment module through the translation stage fixing screw, and the miniature electric lifting platform in the displacement force measurement module is connected and fixed with the electric lifting platform base arranged on the base plate of the support adjustment module through four miniature electric lifting platform fastening bolts. The pressure imprinting motion module comprises a mirror group packaging box, a mirror seat, a mirror, a circular cross-section rubber ring, a focusing lens, a square lower wedge plate, a circular upper wedge plate, a single-degree-of-freedom flexible mechanism, a ring-shaped piezoelectric stack, a diamond indenter, a mirror adjusting bolt, a focusing lens X-axis fine adjustment stud, a square cross-section rubber ring, a diamond indenter locking bolt, a locking nut, a wedge block pre-tightening bolt, a focusing lens Y-axis fine adjustment stud, a mirror seat and flexible mechanism fastening bolt, a cylindrical rubber plug and a mirror fastening screw, wherein the mirror group packaging box is fixedly connected with the mirror seat bottom plate through the precise force gauge fixed connection pad bolt, the mirror is placed in the circular groove of the mirror seat bottom plate and is fixed by the fastening bolt and the rubber plug, the mirror seat is fixedly connected with the mirror seat bottom plate by the mirror seat bottom plate fastening bolt, the mirror group packaging box and the single-degree-of-freedom flexible mechanism are connected and fixed by four fastening bolts, the circular cross-section rubber ring, the laser focusing lens and the square cross-section rubber ring are sequentially placed in the axial space formed by the stepped through holes from bottom to top to form a sandwich structure, the square lower wedge plate is placed in the first step of the single-degree-of-freedom flexible mechanism, meanwhile, the circular upper wedge plate is placed in the groove of the square lower wedge plate, the ring-shaped piezoelectric stack and the diamond indenter are sequentially placed in the axial tapered hole at the top of the single-degree-of-freedom flexible mechanism, the front and back ends of the ring-shaped piezoelectric stack act on the bottom of the diamond indenter and the plane of the circular upper wedge plate, respectively, the diamond indenter is clamped and fixed by the diamond indenter locking bolt and the locking nut, the square lower wedge plate is driven to move along the X-axis in the square groove at the bottom of the flexible mechanism by the pre-tightening bolt, indirectly driving the circular upper wedge plate to move along the Z-axis in the circular hole in the middle of the flexible mechanism, realizing the axial pre-tightening of the ring-shaped piezoelectric stack, and the upper and lower wedge plates, the piezoelectric stack and the diamond indenter all adopt a hollow structure to avoid blocking the light path. The laser irradiation module comprises a pulsed laser, a laser base mounting table, a laser base, a two-dimensional manual X-axis translation table, a two-dimensional manual Z-axis translation table, a laser front-end Z-axis pose adjustment bolt, a laser rear-end Z-axis pose adjustment bolt, a laser front-end X-axis pose adjustment bolt, a laser rear-end X-axis pose adjustment bolt, a rubber protection ring, a two-dimensional displacement table Z-axis adjustment rod, a two-dimensional displacement table X-axis adjustment rod, a laser positioning bolt, a laser fastening bolt, and a laser base mounting table fastening bolt, wherein two rubber rings are sleeved on the front and rear ends of the laser respectively; the laser is coaxially arranged in the through hole of the mounting base, the laser front-end Z-axis pose adjustment bolt, the laser rear-end Z-axis pose adjustment bolt, the laser front-end X-axis pose adjustment bolt, and the laser rear-end X-axis pose adjustment bolt are screwed into the mounting base, the laser mounting base is fixedly connected with the laser base mounting table through the fastening bolt, and the laser base mounting table is fixedly connected with the Z-axis translation table of the two-dimensional manual displacement table through the laser base mounting table fastening bolt; the two-dimensional manual X-axis translation table, the two-dimensional manual Z-axis translation table, the two-dimensional displacement table Z-axis adjustment rod, and the two-dimensional displacement table X-axis adjustment rod are assembled and fixed on the laser displacement table base by using the translation table fixing screw. The displacement force measurement module comprises a miniature electric lifting platform, a force gauge mounting seat, a precision force gauge, a mirror seat bottom plate, a mirror seat bottom plate fastening bolt, a force gauge fastening bolt, a force gauge mounting bottom plate fastening bolt, and a miniature electric lifting platform fastening bolt, wherein the miniature electric lifting platform is fixedly connected with the electric lifting platform base arranged on the base plate through four miniature electric lifting platform fastening bolts, the force gauge mounting seat is connected and installed with the miniature electric lifting platform through four force gauge mounting bottom plate fastening bolts, the precision force gauge is fixedly connected with the installation base thereof through four force gauge fastening bolts, and the mirror seat bottom plate is fixedly installed with the mirror seat bottom plate through four mirror seat bottom plate fastening bolts in the reverse direction. 2.The device according to claim 1, wherein: The support adjustment module comprises a gantry mounting beam, a base plate, gantry columns, a laser displacement table base, an electric lifting platform base, translation table fixing screws, column base plate fastening bolts, and an electric lifting platform fixing screw, wherein the laser displacement table base and the electric lifting platform mounting seat are connected and installed with the base plate through a plurality of groups of translation table fixing screws, column base plate fastening bolts, and electric lifting platform fixing screws, and the gantry mounting beam is fixedly connected with the two gantry columns through beam column fixing screws. 3.The device according to claim 1, wherein: The ultrasonic vibration module comprises an ultrasonic transducer, an ultrasonic amplitude transformer, an ultrasonic amplitude transformer flange cover plate, a sample mounting clamp, a fixing bolt, a clamp transducer fixing bolt, a flange cover plate fixing bolt, a beam and column fixing stud, a lock washer, a beam nut and a sample clamping stud, wherein the fixing stud is connected with a threaded hole at the tail of the ultrasonic amplitude transformer after passing through a through hole of the ultrasonic transducer, the sample mounting clamp is connected with a threaded hole at the head of the ultrasonic amplitude transformer by the fixing bolt, and the test sample is positioned and clamped by the clamping stud and the sample mounting clamp; the ultrasonic amplitude transformer is coaxially placed in a stepped through hole of a gantry mounting beam through the flange structure at the middle, and is fastened in the stepped through hole of the gantry mounting beam by the ultrasonic amplitude transformer flange cover plate and six flange cover plate fixing bolts.

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