A method and system for detecting residual stress of a ceramic material

Abstract

This invention provides a method and system for detecting residual stress in ceramic materials, comprising: grinding a target location using a laser engraving machine; after grinding, attaching a strain gauge to the target location and connecting the attached strain gauge to a strain acquisition device; designing a target drilling path based on the drilling position of the strain gauge in the laser engraving machine software terminal; drilling holes in the ceramic material to be tested using the laser engraving machine according to the target drilling path; after drilling, inputting the collected strain data into a residual stress analysis terminal, which calculates the residual stress result data. This invention, by using a laser engraving machine to drill holes in the ceramic material and automatically calculating the residual stress result data using a residual stress analysis terminal, achieves residual stress detection in ceramic materials. This can be used for production guidance of ceramic materials, thereby improving the production quality of ceramic products and solving risks and hidden dangers in later use.

Description

Technical Field

[0001] This invention relates to the field of ceramic material performance testing technology, and in particular to a method and system for detecting residual stress in ceramic materials. Background Technology

[0002] Non-uniform mechanical deformation, temperature changes, and phase transformations caused by manufacturing processes often lead to non-uniform plastic deformation in materials. After the external forces are removed, the residual plastic deformation exerts its effect on the material, resulting in corresponding elastic deformation within the material to maintain the equilibrium of the component and generating internal stress, known as internal stress. Internal stress exists over a large area of ​​the material and is considered uniform. The associated internal forces and moments remain in equilibrium across all cross-sections of the object; this is called residual stress. The presence of residual stress makes the material prone to deformation and cracking during use, affecting its service life.

[0003] There are two main categories of methods for detecting residual stress: non-destructive testing (NDT) and destructive testing (DDT). These methods are well-established and have been developed into standards for testing residual stress in metal components and materials. However, there are currently no relevant standards or mature testing methods for detecting residual stress in ceramic materials. Especially with the rise of architectural ceramic materials such as slabs, the presence of residual stress makes these slabs prone to breakage during processing and use, severely hindering the development of these materials.

[0004] The blind hole method, as an effective residual stress detection method, is well-established in the application of metallic materials. Its principle involves drilling a small hole in the material surface with a drill bit to release the stress at the test point. The magnitude of the released residual stress is then calculated by measuring the deformation sensed by strain gauges. However, due to the high hardness and wear resistance of ceramic materials, ordinary drill bits cannot be used for drilling. Even with diamond drill bits, the high heat generation leads to inaccurate measurement results. Furthermore, the high cost of drill bits makes the blind hole method difficult to apply to residual stress detection in ceramic materials. Therefore, there is currently no suitable method for residual stress detection in ceramic materials.

[0005] Therefore, existing technologies have shortcomings and need to be improved and developed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method and system for detecting residual stress in ceramic materials, in order to address the above-mentioned deficiencies of the prior art and solve the problem that there is no applicable method for detecting residual stress in ceramic materials in the prior art.

[0007] The technical solution adopted by this invention to solve the technical problem is as follows:

[0008] A method for detecting residual stress in ceramic materials, the method being based on a residual stress system for ceramic materials, the residual stress system comprising: a laser engraving machine, a strain acquisition device, and a residual stress analysis terminal connected to the strain acquisition device;

[0009] The method for detecting residual stress in ceramic materials includes:

[0010] The target area on the surface of the ceramic material to be tested, where the strain pattern is to be applied, is polished using a laser engraving machine.

[0011] After polishing, the strain gauge is attached to the surface of the ceramic material to be tested at the target location, and the attached strain gauge is connected to the strain acquisition device.

[0012] In the laser engraving machine software terminal, the target drilling path is designed according to the drilling position of the strain flower;

[0013] Using a laser engraving machine, holes are drilled in the ceramic material to be tested according to the target drilling path;

[0014] After drilling is completed, the strain acquisition device inputs the acquired strain data into the residual stress analysis terminal, which then calculates the residual stress result data.

[0015] In one implementation, the step of using a laser engraving machine to grind the target location on the surface of the ceramic material to be tested, where the strain pattern is to be applied, includes:

[0016] An ice box containing ice is placed on the worktable of the laser engraving machine;

[0017] The ceramic material to be tested is placed on the ice box, and the hole to be drilled is located in the middle of the ice box;

[0018] Turn on the laser engraving machine and grind the target area on the surface of the ceramic material to be tested where the strain pattern will be applied;

[0019] The laser wavelength used for polishing is 355nm, the pulse width is 5-30ns, the frequency is 5-30Hz, the power is 3-30W, and the number of polishing cycles is 1-5.

[0020] In one implementation, after the grinding is completed, a strain gauge is attached to the surface of the ceramic material to be tested corresponding to the target location, and the attached strain gauge is connected to the strain acquisition device, including:

[0021] After polishing, the strain gauge is glued to the surface of the ceramic material to be tested at the target location.

[0022] The position of the strain gauge is fixed by using a ring terminal, and the strain gauge is connected to the strain acquisition device;

[0023] The strain rose includes three strain units with sensitive grid angles of 0°, 45° and 90° respectively.

[0024] In one implementation, before designing the drilling path based on the drilling position of the strain gauge in the laser engraving machine software terminal, the method further includes:

[0025] Input the elastic modulus and Poisson's ratio of the ceramic material to be tested into the residual stress analysis software on the residual stress analysis terminal.

[0026] In one implementation, designing the target drilling path based on the drilling position of the strain gauge in the laser engraving machine software terminal includes:

[0027] Turn on the laser engraving machine and adjust the laser head position to align with the drilling position of the strain gauge.

[0028] Design the target drilling path and perform a focusing operation;

[0029] The laser engraving machine has a laser wavelength of 355nm and uses a 3D galvanometer scanning head. The diameter of the target hole is 0.5-3mm, and the depth of the target hole is 1.2 times the diameter.

[0030] In one implementation, the target hole-punching path specifically includes:

[0031] In the laser engraving machine software terminal, a first circular path with the same diameter as the target hole size is generated based on the target hole size;

[0032] Select internal fill, set the line angle to 45°, set the line spacing to 0.01mm, and select evenly distributed fill lines;

[0033] Select the first circular path after filling and perform overall calculation, then circle around the first circular path once;

[0034] Define a second circular path, the diameter of which is smaller than the target drilling size;

[0035] Select internal fill, set the line angle to 135°, perpendicular to the laser line of the first circular path, set the line spacing to 0.01mm, and select evenly distributed fill lines;

[0036] Select the filled second circular path and perform an overall calculation, then circle around the second circular path once;

[0037] The centers of the first and second circular paths are overlapped to complete the design of the drilling path.

[0038] In one implementation, the residual stress system for ceramic materials further includes: a ventilation device for removing powder generated by the laser engraving machine during drilling;

[0039] The process of using a laser engraving machine to drill holes in the ceramic material to be tested according to the target drilling path includes:

[0040] Using a laser engraving machine, holes are drilled in the ceramic material to be tested according to the target drilling path, while the exhaust device is turned on.

[0041] The laser engraving machine has a laser power of 3-30W, a focused pulse beam diameter of 0.02-0.05mm, a pulse width of 5-30ns, and a frequency of 5-30Hz.

[0042] The exhaust device has a suction power of 1-10 kPa and an air volume of 10-100 m³ / h. 3 / h, the distance between the exhaust port of the exhaust device and the laser drilling position is 0.1-1m;

[0043] The laser engraving machine adopts a non-continuous working mode, and works continuously for 1-10 cycles according to the set parameters. The depth of each operation is 0.005-0.05mm. After each operation, there is an interval of 10-60 seconds before the next operation is carried out, until the depth of the target hole size is reached.

[0044] In one implementation, after drilling is completed, the strain acquisition device inputs the acquired strain data into the residual stress analysis terminal, which calculates the residual stress result data, including:

[0045] After drilling is completed, the stable strain value is acquired through the strain acquisition device;

[0046] The residual stress analysis terminal acquires the strain value;

[0047] The residual stress analysis software in the residual stress analysis terminal calculates the residual stress result data based on the elastic modulus and Poisson's ratio.

[0048] In one implementation, the residual stress result data includes: maximum principal stress, minimum principal stress, 0-degree angle, and equivalent stress.

[0049] This invention also discloses a residual stress detection system for ceramic materials, comprising:

[0050] Laser engraving machines are used to grind the target positions on the surface of ceramic materials to be tested, and to drill holes in the ceramic materials to be tested according to the target drilling path.

[0051] The strain acquisition device is used to connect with the strain rosette pasted on the surface of the ceramic material to be tested at the target location after grinding, and to input the acquired strain data into the residual stress analysis terminal after drilling.

[0052] A residual stress analysis terminal, which is connected to the strain acquisition device, is used to acquire the released strain and calculate the residual stress result data;

[0053] A ventilation device is used to remove the powder generated by the laser engraving machine during drilling.

[0054] This invention provides a method and system for detecting residual stress in ceramic materials. The method is based on a residual stress system, which includes a laser engraving machine, a strain gauge, and a residual stress analysis terminal connected to the strain gauge. The method includes: using the laser engraving machine to grind the target location on the surface of the ceramic material to be tested, where a strain gauge should be attached; after grinding, attaching the strain gauge to the surface of the ceramic material at the target location, and connecting the attached strain gauge to the strain gauge; designing a target drilling path in the laser engraving machine software terminal based on the drilling location of the strain gauge; using the laser engraving machine to drill holes in the ceramic material to be tested according to the target drilling path; after drilling, inputting the collected strain data into the residual stress analysis terminal, which calculates the residual stress result data. This invention utilizes a laser engraving machine to drill holes in ceramic materials and a residual stress analysis terminal to automatically calculate the residual stress results, thereby enabling residual stress detection in ceramic materials. This can be used to guide the production of ceramic materials, thereby improving the production quality of ceramic products and resolving risks and hidden dangers in later use. Attached Figure Description

[0055] Figure 1 This is a flowchart of a preferred embodiment of the method for detecting residual stress in ceramic materials according to the present invention.

[0056] Figure 2 This is a flowchart of step S100 in a preferred embodiment of the residual stress detection method for ceramic materials in this invention.

[0057] Figure 3 This is a flowchart of step S200 in a preferred embodiment of the residual stress detection method for ceramic materials in this invention.

[0058] Figure 4 This is a flowchart of step S300 in a preferred embodiment of the residual stress detection method for ceramic materials in this invention.

[0059] Figure 5 This is a flowchart of step S320 in a preferred embodiment of the residual stress detection method for ceramic materials in this invention.

[0060] Figure 6 This is a flowchart of step S500 in a preferred embodiment of the residual stress detection method for ceramic materials in this invention. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0062] Currently, there is no comprehensive technology on the market for detecting residual stress in ceramic materials. This invention introduces a laser engraving method to successfully detect residual stress in ceramic materials by utilizing the amount of deformation released by the material, thus filling the gap in residual stress detection in the ceramic industry.

[0063] Please see Figure 1 , Figure 1 This is a flowchart of the method for detecting residual stress in ceramic materials according to the present invention. The method for detecting residual stress in ceramic materials is based on a residual stress system for ceramic materials, which includes: a laser engraving machine, a strain gauge, and a residual stress analysis terminal connected to the strain gauge.

[0064] like Figure 1 As shown, the method for detecting residual stress in ceramic materials according to an embodiment of the present invention includes the following steps:

[0065] Step S100: Use a laser engraving machine to grind the target position on the surface of the ceramic material to be tested, where the strain pattern is to be applied.

[0066] In one implementation, please refer to Figure 2 Step S100 includes:

[0067] Step S110: Place an ice box containing ice cubes on the worktable of the laser engraving machine;

[0068] Step S120: Place the ceramic material to be tested on the ice box, with the hole to be drilled located in the middle of the ice box;

[0069] Step S130: Turn on the laser engraving machine and grind the target position on the surface of the ceramic material to be tested where the strain pattern is to be applied.

[0070] This invention solves the problem of residual stress testing in the field of ceramic materials. Traditional blind-hole methods are difficult to use for drilling on ceramic material surfaces, and the heat generated during drilling also affects the accuracy of the test, failing to meet the requirements for residual stress testing in ceramic materials. Therefore, this invention uses a laser engraving machine for drilling and utilizes an ice box for cooling, avoiding the influence of heat during drilling on the measurement results.

[0071] Specifically, place an ice box filled with ice on the worktable of the laser engraving machine, place the ceramic material on the ice box, with the desired drilling point in the center of the ice box, turn on the laser engraving machine, and use the laser engraving machine to polish the surface of the ceramic material at the area where the strain pattern needs to be applied. The laser wavelength during polishing is 355nm, the pulse width is 5-30ns, the frequency is 5-30Hz, the power is 3-30W, and the polishing is performed 1-5 times.

[0072] After step S100, the process is as follows: Step S200, after grinding, the strain gauge is pasted onto the surface of the ceramic material to be tested corresponding to the target position, and the pasted strain gauge is connected to the strain acquisition device.

[0073] In one implementation, please refer to Figure 3 Step S200 specifically includes:

[0074] Step S210: After polishing, the strain gauge is glued to the surface of the ceramic material to be tested at the target position.

[0075] Step S220: Fix the position of the strain gauge using the annular terminal and connect the strain gauge to the strain acquisition device.

[0076] Specifically, the strain gauge is glued to the surface of the polished ceramic material, and its position is fixed with a ring terminal, which is then connected to the strain acquisition device. The strain gauge includes three strain units (sensitive grids) with angles of 0°, 45°, and 90°, used to record strain values ​​in three directions.

[0077] The step following step S200 is: Step S300, designing the target drilling path in the laser engraving machine software terminal according to the drilling position of the strain flower.

[0078] Specifically, the residual stress analysis terminal has residual stress analysis software, such as Sigma synthesis testing software, and the residual stress analysis terminal is connected to the strain acquisition device before drilling.

[0079] In one implementation, before step S300, the method further includes inputting the elastic modulus and Poisson's ratio of the ceramic material to be tested into the residual stress analysis software on the residual stress analysis terminal. The elastic modulus and Poisson's ratio are actual measured values; for example, the elastic modulus and Poisson's ratio of a building ceramic slab are 70 GPa and 0.23, respectively. The elastic modulus and Poisson's ratio are used to calculate the residual stress result data.

[0080] In one embodiment, please refer to Figure 4 Step S300 specifically includes:

[0081] Step S310: Turn on the laser engraving machine and adjust the laser head position to align with the drilling position of the strain flower;

[0082] Step S320: Design the target drilling path and perform focusing operation.

[0083] Specifically, the laser engraving machine is turned on, the laser head is adjusted to align with the drilling position of the strain gauge, the drilling path is designed, and focusing is performed. The laser engraving machine uses a laser wavelength of 355nm and a 3D galvanometer scanning head. The diameter D of the target drilling size is 0.5-3mm, and the depth of the target drilling size is 1.2×D.

[0084] In one embodiment, please refer to Figure 5 The "design target drilling path" in step S320 specifically includes:

[0085] Step S321: In the laser engraving machine software terminal, according to the target hole size, formulate a first circular path with the same diameter as the target hole size;

[0086] Step S322: Select internal fill, set the line angle to 45°, set the line spacing to 0.01mm, and select evenly distributed fill lines;

[0087] Step S323: Select the first circular path after filling and perform overall calculation, then circle around the first circular path once;

[0088] Step S324: Define a second circular path, wherein the diameter of the second circular path is smaller than the target drilling size;

[0089] Step S325: Select internal fill, set the line angle to 135°, perpendicular to the laser line of the first circular path, set the line spacing to 0.01mm, and select evenly distributed fill lines;

[0090] Step S326: Select the filled second circular path and perform an overall calculation, then circle around the second circular path once;

[0091] Step S327: Overlap the centers of the first circular path and the second circular path to complete the design of the drilling path.

[0092] In other words, based on the required drilling size (i.e., the target drilling size), a first circular path of the same size as the target drilling size is created. Internal fill is selected, the line angle is set to 45°, the line spacing is set to 0.01mm, and evenly distributed fill lines are selected. The entire object (i.e., the first circular path after filling) is selected and calculated, traversing the first circular path once. Then, a second circular path with a size 0.05-0.2mm smaller than the required drilling size is created. Internal fill is selected, the line angle is set to 135°, perpendicular to the laser lines of the first circular path, and the line spacing is set to 0.01mm. Evenly distributed fill lines are selected, and the entire object (i.e., the second circular path after filling is 0.05-0.2mm smaller than the required drilling size) is selected and calculated, traversing the edge once. The centers of the two circular paths are overlapped, and the two objects are placed in the same position, thus completing the drilling path design. Paths designed using this method can produce holes with good perpendicularity that meet testing requirements.

[0093] Following step S300 is step S400: using a laser engraving machine, holes are drilled in the ceramic material to be tested according to the target drilling path. Specifically, after focusing is completed, the laser engraving machine is turned on to perform the drilling operation.

[0094] In one implementation, the residual stress system for the ceramic material further includes a ventilation device for removing powder generated during the laser engraving machine's drilling process. Step S400 specifically involves using the laser engraving machine to drill holes in the ceramic material to be tested along the target drilling path, while simultaneously activating the ventilation device. The laser engraving machine has a laser power of 3-30W, a focused pulse beam diameter of 0.02-0.05mm, a pulse width of 5-30ns, and a frequency of 5-30Hz. The ventilation device has a suction power of 1-10KPa and an airflow of 10-100m³ / h. 3 The distance between the exhaust port of the ventilation device and the laser drilling position is 0.1-1m. The laser engraving machine adopts a non-continuous working mode, continuously working for 1-10 cycles according to the set parameters, with each cycle having a depth of 0.005-0.05mm. After each cycle, there is an interval of 10-60 seconds before the next cycle begins, until the target drilling depth is reached. In other words, the laser working mode is step-by-step. According to the set parameters, the laser uses a non-continuous processing mode, with each cycle having a depth of 0.005-0.05mm. After each cycle, there is an interval of 10-60 seconds before the next cycle begins, repeating this process until the hole depth is 1.2×D, completing the drilling operation. The strain acquisition device records the strain values ​​in different directions after the final stabilization.

[0095] After step S400, the procedure is as follows: Step S500, after drilling is completed, the strain acquisition device inputs the acquired strain data into the residual stress analysis terminal, and the residual stress analysis terminal calculates the residual stress result data.

[0096] In one embodiment, please refer to Figure 6 Step S500 specifically includes:

[0097] Step S510: After drilling is completed, the stable strain value is acquired through the strain acquisition device;

[0098] Step S520: The residual stress analysis terminal acquires the strain value;

[0099] Step S530: The residual stress analysis software in the residual stress analysis terminal calculates the residual stress result data based on the elastic modulus and Poisson's ratio.

[0100] Specifically, after drilling is completed, strain values ​​in the 0°, 45° and 90° directions of the stabilized strain rosette are collected by the strain acquisition device. Combined with the input elastic modulus and Poisson's ratio, the Sigma integrated testing software automatically calculates the residual stress data through the calculation formula, thereby completing the detection of residual stress at the drilling point.

[0101] In one implementation, the residual stress data includes: maximum principal stress, minimum principal stress, 0-degree angle, and equivalent stress. By using the residual stress data, the characterization of residual stress in ceramic materials is solved, which guides production and helps address problems such as deformation and cracking during later use of ceramic materials.

[0102] Thus, this invention employs a laser engraving machine for drilling, which is fast and precise. The laser is a cold light source, minimizing the heat impact of drilling. Combined with process settings to reduce the heat impact and improve drilling accuracy, this enhances the precision of residual stress detection in ceramics. Using the detection method of this invention to measure the magnitude of residual stress in ceramic materials and to guide ceramic production can improve the production quality of ceramic products and address risks and hidden dangers in later use. The residual stress detection method for ceramic materials developed in this invention can accurately measure the magnitude of residual stress in ceramic materials, filling a gap in domestic and international residual stress detection for ceramic materials.

[0103] This invention also discloses a residual stress detection system for ceramic materials, characterized in that it comprises:

[0104] Laser engraving machines are used to grind the target positions on the surface of ceramic materials to be tested, and to drill holes in the ceramic materials to be tested according to the target drilling path.

[0105] The strain acquisition device is used to connect with the strain rosette pasted on the surface of the ceramic material to be tested at the target location after grinding, and to input the acquired strain data into the residual stress analysis terminal after drilling.

[0106] A residual stress analysis terminal, which is connected to the strain acquisition device, is used to acquire the released strain and calculate the residual stress result data;

[0107] A ventilation device is used to remove the powder generated by the laser engraving machine during drilling; specifically as described above.

[0108] In summary, this invention discloses a method and system for detecting residual stress in ceramic materials. The method is based on a residual stress system, which includes a laser engraving machine, a strain gauge, and a residual stress analysis terminal connected to the strain gauge. The method comprises: using the laser engraving machine to grind the target location on the surface of the ceramic material to be tested, where a strain gauge should be attached; after grinding, attaching the strain gauge to the surface of the ceramic material to be tested corresponding to the target location, and connecting the attached strain gauge to the strain gauge; designing a target drilling path in the laser engraving machine software terminal according to the drilling location of the strain gauge; using the laser engraving machine to drill holes in the ceramic material to be tested according to the target drilling path; after drilling, the strain gauge inputs the collected strain data into the residual stress analysis terminal, which calculates the residual stress result data. This invention utilizes a laser engraving machine to drill holes in ceramic materials and a residual stress analysis terminal to automatically calculate the residual stress results, thereby enabling residual stress detection in ceramic materials. This can be used to guide the production of ceramic materials, thereby improving the production quality of ceramic products and resolving risks and hidden dangers in later use.

[0109] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for detecting residual stress of a ceramic material, the method for detecting residual stress of a ceramic material being based on a system for realizing residual stress of a ceramic material, characterized by, The ceramic material residual stress system comprises a laser engraving machine, a strain collector and a residual stress analysis terminal connected with the strain collector. The ceramic material residual stress detection method comprises: The laser engraving machine is used to polish the target position of the surface of the ceramic material to be tested for the strain gauge to be attached; After polishing, the strain gauge is attached to the surface of the ceramic material to be tested corresponding to the target position, and the attached strain gauge is connected with the strain collector; In the laser engraving machine software terminal, a target punching path is designed according to the punching position of the strain gauge; The laser engraving machine is used to punch the ceramic material to be tested according to the target punching path; After punching, the strain data collected by the strain collector is input into the residual stress analysis terminal, and the residual stress result data is calculated by the residual stress analysis terminal; The laser engraving machine is used to polish the target position of the surface of the ceramic material to be tested for the strain gauge to be attached; An ice box is placed on the workbench of the laser engraving machine, and the ice box contains ice blocks; The ceramic material to be tested is placed on the ice box, and the position to be punched is located at the middle position of the ice box; The laser engraving machine is turned on to polish the target position of the surface of the ceramic material to be tested for the strain gauge to be attached; The laser wavelength during polishing is 355 nm, the pulse width is 5-30 ns, the frequency is 5-30 Hz, the power is 3-30 W, and the polishing frequency is 1-5 times; The laser engraving machine is turned on, and the laser head position is adjusted to align with the punching position of the strain gauge; The target punching path is designed, and the focusing operation is performed; The laser wavelength of the laser engraving machine is 355 nm, and a 3D galvanometer scanning head is used, the diameter of the target punching size is 0.5-3 mm, and the depth of the target punching size is 1.2 times the diameter; The target punching path is designed as follows: In the laser engraving machine software terminal, a first circular ring path with the same diameter as the target punching size is formulated according to the target punching size; Internal filling is selected, the line angle is set to 45°, the line spacing is set to 0.01 mm, and the average distribution of the filling line is selected; The selected filled first circular ring path is calculated as a whole, and is wound once along the first circular ring path; A second circular ring path is formulated, the diameter of the second circular ring path is smaller than that of the target punching size, and the difference between the diameters of the first circular ring path and the second circular ring path is 0.05-0.2 mm; Internal filling is selected, the line angle is set to 135°, the laser line of the first circular ring path is perpendicular to the laser line of the second circular ring path, the line spacing is set to 0.01 mm, and the average distribution of the filling line is selected; The selected filled second circular ring path is calculated as a whole, and is wound once along the second circular ring path; The centers of the first circular ring path and the second circular ring path are overlapped, and the punching path design is completed; The ceramic material residual stress system further comprises an air extraction device for removing the powder generated by the laser engraving machine during punching. ​ The laser engraving machine is used to punch the ceramic material to be tested according to the target punching path, and the exhaust device is turned on at the same time. The laser power of the laser engraving machine is 3-30 W, the diameter of the focused pulse light beam is 0.02-0.05 mm, the pulse width is 5-30 ns, and the frequency is 5-30 Hz. The laser engraving machine adopts a discontinuous working mode, and works continuously for 1-10 cycles each time according to the set parameters, the action depth is 0.005-0.05 mm each time, and the next work is performed after an interval of 10-60 seconds each time until the depth of the target punching size is reached. The suction device has a suction force of 1-10 KPa and an air volume of 10-100 m 3 / h, and the distance between the suction port of the suction device and the laser drilling position is 0.1-1 m. After polishing, the strain rosette is pasted on the surface of the target position corresponding to the ceramic material to be tested, and the pasted strain rosette is connected with the strain collector, comprising:

2. The method of claim 1, wherein After polishing, the strain rosette is pasted on the surface of the target position corresponding to the ceramic material to be tested by glue; The position of the strain rosette is fixed by the ring terminal, and the strain rosette is connected with the strain collector; The strain rosette includes three strain units, and the sensitive grid angles are 0°, 45° and 90° respectively. Before designing the punching path in the laser engraving machine software terminal according to the punching position of the strain rosette, it further comprises:

3. The method of claim 2, wherein the ceramic material is a ceramic material according to any one of claims 1 to 7. The elastic modulus and Poisson's ratio of the ceramic material to be tested are input into the residual stress analysis software on the residual stress analysis terminal. After punching, the strain data collected by the strain collector is input into the residual stress analysis terminal, and the residual stress result data is calculated by the residual stress analysis terminal, comprising:

4. The method of claim 3, wherein the ceramic material is a ceramic material according to any one of claims 1 to 2. After punching, the stable strain value is collected by the strain collector; The residual stress analysis terminal acquires the strain value; The residual stress analysis software in the residual stress analysis terminal calculates the residual stress result data according to the elastic modulus and Poisson's ratio. The residual stress result data includes: maximum principal stress, minimum principal stress, 0 degree angle and equivalent stress.

5. The method of claim 1, wherein It comprises:

6. A ceramic material residual stress detection system characterized by, A laser engraving machine is used to polish the target position of the ceramic material to be tested on which the strain rosette is to be pasted, and to punch the ceramic material to be tested according to the target punching path; A strain collector is used to connect with the strain rosette pasted on the surface of the target position corresponding to the ceramic material to be tested after polishing, and to input the collected strain data into the residual stress analysis terminal after punching; A residual stress analysis terminal is connected with the strain collector, used to collect the released strain and calculate the residual stress result data; An exhaust device is used to remove the powder generated by the laser engraving machine during punching. ​ The target position of the ceramic material surface to be pasted with the strain rosette is polished, including: placing an ice box on the workbench of a laser engraving machine, the ice box containing ice blocks; placing the ceramic material to be tested on the ice box, and the position to be punched is located at the middle position of the ice box; turning on the laser engraving machine to polish the target position of the ceramic material surface to be pasted with the strain rosette; wherein the laser wavelength during polishing is 355 nm, the pulse width is 5-30 ns, the frequency is 5-30 Hz, the power is 3-30 W, and the polishing times are 1-5 times; A target punching path is designed in the laser engraving machine software terminal according to the punching position of the strain rosette, including: turning on the laser engraving machine, adjusting the position of the laser head to align with the punching position of the strain rosette; designing a target punching path and performing focusing operation; wherein the laser wavelength of the laser engraving machine is 355 nm, and a 3D galvanometer scanning head is used, the diameter of the target punching size is 0.5-3 mm, and the depth of the target punching size is 1.2 times the diameter; The design steps of the target punching path specifically include: in the laser engraving machine software terminal, according to the target punching size, a first circular ring path with the same diameter as the target punching size is formulated; selecting internal filling, setting the line angle to 45°, setting the line spacing to 0.01 mm, and selecting average distribution filling line; selecting the filled first circular ring path for overall calculation, and winding once along the first circular ring path; formulating a second circular ring path, the diameter of the second circular ring path is smaller than the target punching size; selecting internal filling, setting the line angle to 135°, perpendicular to the laser line of the first circular ring path, setting the line spacing to 0.01 mm, and selecting average distribution filling line; selecting the filled second circular ring path for overall calculation, and winding once along the second circular ring path; overlapping the centers of the first circular ring path and the second circular ring path to complete the design of the punching path; According to the target drilling path, the ceramic material to be tested is drilled, comprising: using a laser engraving machine, drilling the ceramic material to be tested according to the target drilling path, and simultaneously starting an air extraction device; the laser power of the laser engraving machine is 3-30W, the diameter of the focused pulse light beam is 0.02-0.05mm, the pulse width is 5-30ns, and the frequency is 5-30Hz; the suction force of the air extraction device is 1-10KPa, the air volume is 10-100m 3 / h, the distance between the air extraction port of the air extraction device and the laser drilling position is 0.1-1m; the laser engraving machine adopts a discontinuous working mode, continuously works for 1-10 cycles at a time according to the set parameters, the depth of each action is 0.005-0.05mm, and the next work is carried out after an interval of 10-60 seconds after each action until the depth of the target drilling size is reached; The difference between the diameters of the first circular ring path and the second circular ring path is 0.05-0.2 mm.

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