A laser cladding sample impact testing machine

Abstract

The application discloses a kind of laser cladding sample impact testing machines, including projectile pipeline, base, fixture, protection device and data acquisition processing control system;The piston rod side coaxial sleeve is in the projectile pipeline, projectile pipeline top is provided with filling port, and projectile is filled in projectile pipeline and is close to piston rod;Projectile pipeline bottom is provided with blocking device, and the position of projectile is fixed by blocking device, to ensure that projectile is in the same position when impact test each time, reduce test error;Projectile pipeline length is greater than the maximum stroke of cylinder;Projectile in projectile pipeline is impacted and collides after being launched by piston rod and impacts on the surface of sample to be tested, and finally completes the impact performance test of sample.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of impact test of metal material, in particular to a laser cladding sample impact testing machine. BACKGROUND

[0002] Impact test is one of the most important methods for determining the impact resistance of materials. The principle is to use a pendulum, drop hammer or other specified mass of impact material to adjust the height so that it can obtain a certain kinetic energy by free fall or external driving, and then impact the sample, and further obtain the test parameters such as the morphology and absorbed energy of the material after impact. The impact resistance of metal materials is one of the important parameters of plate or coating materials. Impact test is usually carried out using an impact testing machine.

[0003] High-speed laser cladding technology is a new surface modification technology. By irradiation of a laser, the metal powder sprayed on the surface of the metal material is melted and rapidly solidified, thereby achieving the effect of surface repair and improvement of material surface performance. Currently, research is being conducted on the impact resistance, tensile resistance, wear resistance and corrosion resistance of materials after laser cladding.

[0004] Unlike ordinary metal plates, the cladding powder and the base material are usually made of different metal materials, and the mechanical properties of the two are different. In addition, defects may occur in the coating during the preparation process due to the characteristics of rapid cooling and heating and process parameters. Therefore, the impact mechanical properties of high-speed laser cladding materials are crucial for evaluating the performance of materials after laser cladding. Existing impact test equipment, such as pendulum impact testing machines, converts gravitational potential energy into impact kinetic energy by lifting the pendulum and allowing it to fall freely, thereby calculating the energy absorbed by the impacted sample. The test has high requirements for sample size and morphology, and the impact surface shape of the pendulum and drop hammer is single, which cannot simulate the impact of the actual material in the environment, and cannot meet the needs of impact testing of laser cladding materials. SUMMARY

[0005] The present application provides a laser cladding sample impact testing machine to meet the needs of impact testing of laser cladding materials.

[0006] The present application adopts the following technical solution: a laser cladding sample impact testing machine, comprising a cylinder and a piston rod, the cylinder is divided into a rod cavity, a rodless cavity and an intermediate cavity, three pressure sensors and a gas control reversing valve are arranged in the cylinder, characterized in that it further comprises an elastic body pipeline, a base, a clamp, a protection device and a data acquisition and processing control system.

[0007] The piston rod is coaxially sleeved on one side of the elastic body pipeline, a filling port is arranged at the top of the elastic body pipeline, and the elastic body is filled in the elastic body pipeline close to the piston rod; a blocking device is arranged at the bottom of the elastic body pipeline, the position of the elastic body is fixed through the blocking device, and it is ensured that the elastic body is in the same position each time impact test is performed; a speed measuring sensor is arranged at the outlet of the elastic body pipeline, the speed of the elastic body after overcoming the friction of the pipeline is measured through the speed measuring sensor, and the energy possessed by the elastic body during impact test is further calculated.

[0008] The base is a platform for placing a sample, and a groove is arranged in the middle impact area to ensure that the impact part of the sample to be tested remains suspended, and there are three groups of bolt holes with different distances on both sides of the groove; a strain gauge is attached to the back of the sample;

[0009] The clamps are installed on both sides of the groove, and each side has three groups, which can achieve good clamping effect for samples of different sizes.

[0010] The data acquisition and processing control system is connected with the speed measuring sensor, the strain gauge, the three pressure sensors in the cylinder and the air control reversing valve, the opening and closing of the air control reversing valve in the cylinder is controlled, and the initial speed of the elastic body is further controlled.

[0011] The elastic body in the elastic body pipeline is impacted and collided by the piston rod and is launched to impact the surface of the sample to be tested, and finally the impact performance test of the sample is completed.

[0012] Further, the cylinder converts air pressure into piston rod thrust to complete the driving supply of the entire impact testing machine, and is a double-acting single-rod cylinder.

[0013] Further, a flange plate is arranged on one side of the elastic body pipeline, and the flange plate is connected and fixed with the cylinder.

[0014] Further, the elastic body has three shapes, and the contact between the elastic body and the sample during collision is spherical contact, point contact and line contact respectively, and the tail of the elastic body is a cylinder except the spherical contact, so as to adapt to the reduction of friction of the elastic body pipeline.

[0015] Further, the clamp comprises a bolt, a clamping nut and a pad, the bolt is fixed on the bolt hole of the base, different bolt holes are selected for samples of different sizes, the clamping nut is tightened to fix the pad, and the sample to be tested is fixed.

[0016] Further, a damping sheet is attached to the top end of the piston rod, and the material is rubber.

[0017] Further, the elastic body pipeline is a hollow steel pipe.

[0018] Further, three groups of evenly distributed supports are arranged at the bottom of the elastic body pipeline as supports.

[0019] Further, the protection device is arranged around the base to prevent the sample debris from splashing during the impact test and ensure the safety of the test.

[0020] Further, the length of the elastic body pipeline is greater than the maximum stroke of the cylinder.

[0021] The present application has the following beneficial effects

[0022] Firstly, the laser cladding sample impact testing machine has simple structure, and is not limited to laser cladding samples and has strong versatility. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 The present application has the following beneficial effects

[0024] Figure 2 The present application has the following beneficial effects

[0025] Figure 3 The present application has the following beneficial effects

[0026] Figure 4 The present application has the following beneficial effects

[0027] Figure 5 The present application has the following beneficial effects

[0028] Figure 6 The present application has the following beneficial effects

[0029] The present application has the following beneficial effects DETAILED DESCRIPTION

[0030] As Figure 1As shown, the laser cladding sample impact testing machine provided by the embodiment includes a driving device, a projectile pipeline 2, an impact platform, a detection device, a protection device 6, and a data acquisition and processing control system 11. The driving device includes an air compressor, an air tank, and a cylinder 3, which are mature technologies in the pneumatic field and can be selected according to specific experimental requirements. The improvement of the present application is not in this regard, and therefore, no further description is provided herein. The air compressor drives the air to be compressed into high-pressure gas and delivered into the air tank for storage. The air tank is connected to the cylinder rodless cavity to provide high-pressure air. The cylinder converts the air pressure into the piston rod thrust to complete the driving supply of the entire impact testing machine.

[0031] As shown in Figure 2 The cylinder 3 is the main power element, which converts the internal energy of compressed air into the kinetic energy of the piston rod 10. The cylinder is a double-acting single-rod cylinder, which includes a rod cavity 20, a rodless cavity 23, and an intermediate cavity 21. The intermediate cover 24 has a jet port, which connects the rodless cavity 23 and the rod cavity 20.

[0032] The rod cavity of the cylinder is coaxially sleeved in the projectile pipeline 2. The projectile 1 is placed in the pipeline and is impacted by the piston rod 10 to complete acceleration and launch in the projectile pipeline 2.

[0033] The impact platform includes a base 9 and a clamp 7. The laser cladding sample 8 to be tested is vertically installed on the base 9. The projectile 1 in the projectile pipeline is launched and impacts the surface of the laser cladding sample 8 to be tested, and finally completes the impact performance test of the sample.

[0034] The detection device includes three pressure sensors 15, a speed sensor 19, and a strain gauge 14. The data acquisition and processing control system 11 is a computer data acquisition and power control system.

[0035] The piston rod 10 serves as both a cylinder power output element and an impact rod. The end of the piston rod 10 is provided with a damping sheet 18 with a thickness of 2-5 mm.

[0036] As shown in Figure 5 The projectile pipeline 2 and the piston rod 10 are coaxially installed on the same axis. The inner diameter of the pipeline is 25 mm. The top of the pipeline is provided with a loading port 5 for loading the projectile. The bottom of the projectile pipeline 2 is provided with a blocking device 13, which fixes the position of the projectile in the pipeline and ensures that the projectile is in the same position during each test impact, thereby reducing test errors.

[0037] The projectile 1 is loaded into the pipeline near the piston rod 10 and is fixed in position by the blocking device 13. The material is Q235 steel. The loaded projectile 1 is pre-set in three shapes, as shown in Figure 4As shown, the reason for setting different shapes of the elastic body is to simulate the different forms of damage that the sample material will face in practical applications. The contact with the sample is spherical contact, point contact, and line contact. Except for spherical contact, the tail of the elastic body is a cylinder to reduce friction in the pipeline.

[0038] All the energy possessed by the elastic body impact is controlled by the cylinder 3. A speed sensor 19 is provided at the outlet of the elastic body pipeline 2 to measure the speed of the elastic body 1 after overcoming the friction of the pipeline. The energy possessed by the elastic body 1 during the impact test is further calculated.

[0039] The support 16 is a metal or non-metal support that supports the weight of the entire elastic body pipeline 2 and keeps the elastic body pipeline 2 balanced.

[0040] As shown in Figure 1 , Figure 3 The base 9 is a platform for placing the laser cladding sample 8. It has sufficient mass and a recess 17 in the middle impact area to ensure that the impact area of the workpiece remains suspended. Strain gauges 14 are attached to the back of the sample. Protective devices 6 are provided around the base 9. The material is transparent to prevent debris from the sample from flying during the impact test and to ensure safety during the test.

[0041] As shown in Figure 1 , Figure 6 The clamps 7 are installed on both sides of the recess 17, three groups on each side, which can ensure the best clamping effect for samples of different sizes. The clamps 7 include bolts 7-1, clamping nuts 7-2, and pads 7-3. The bolts 7-1 are fixed to the bolt holes 22 of the base. Different bolt holes are selected for samples of different sizes. The clamping nuts 7-2 are tightened to fix the pads 7-3, thereby fixing the sample 8 to be tested.

[0042] In a specific experimental process, the data acquisition and processing control system 11 controls the power device 4 to provide high-pressure air to the cylinder 3. The high-pressure air in the cylinder 3 drives the piston rod 10 to work, prompting the piston rod 10 to impact the elastic body 1. The elastic body 1 accelerates in the elastic body pipeline 2. After the elastic body 1 is accelerated to a certain impact speed by the piston rod 10, it flies out of the elastic body pipeline 2 with the impact surface in front, and impacts the surface of the laser cladding sample 8 clamped on the base 9.

[0043] The three pressure sensors 15 in the cylinder are connected with the data acquisition and processing control system 11 to monitor the pressure in each chamber in real time. The opening and closing of the pneumatic reversing valve 12 in the cylinder is controlled by the control system to further control the initial speed of the projectile. The velocity sensor 19 outside the projectile pipeline 2 and the strain gauge 14 on the back of the sample are connected with the data recording and processing control system 11 to receive and process the data of the projectile velocity and the sample strain. The data acquisition and processing control system 11 is a high-speed data acquisition system with high sampling rate, high synchronism, high precision, low noise, low distortion and wide test signal range, which can timely and finely capture the high-frequency and instantaneous ultra-dynamic strain signal. The dynamic stress-strain relationship of the laser cladding sample is calculated based on the data collected by the data acquisition and processing control system.

[0044] Obviously, the above embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

Claims

1. A laser cladding sample impact testing machine, comprising a cylinder (3) and a piston rod (10), the cylinder (3) is divided into a rod cavity (20), a rodless cavity (23) and an intermediate cavity (21), three pressure sensors (15) and a pneumatic reversing valve (12) are arranged in the cylinder (3), characterized in that It also includes elastomeric pipeline (2), base (9), clamp (7), protection device (6) and data acquisition processing control system (11); The piston rod (10) is coaxially sleeved in the elastomeric pipeline (2), the top of the elastomeric pipeline (2) is provided with a filling port (5), the elastomeric body (1) is filled in the elastomeric pipeline (2) near the piston rod (10), the bottom of the elastomeric pipeline (2) is provided with a blocking device (13), the position of the elastomeric body is fixed through the blocking device (13), and it is ensured that the elastomeric body is in the same position each time the impact test is performed, a speed sensor (19) is arranged at the outlet of the elastomeric pipeline (2), the speed of the elastomeric body (1) after overcoming the friction of the pipeline is measured through the speed sensor (19), and the energy possessed by the elastomeric body (1) during the impact test is further calculated; The base (9) is a platform for placing the sample (8), the middle impact area is provided with a groove (17) to ensure that the impact part of the sample to be tested remains suspended, and there are three groups of bolt holes (22) with different distances on both sides of the groove (17); the back of the sample is attached with a strain gauge (14); The clamp (7) is installed on both sides of the groove (17), and there are three groups on each side, which can achieve good clamping effect for samples of different sizes; The data acquisition processing control system (11) is connected with the speed sensor (19), the strain gauge (14), the three pressure sensors (15) in the cylinder and the air control reversing valve (12), the opening and closing of the air control reversing valve (12) in the cylinder is controlled, and the initial speed of the elastomeric body is further controlled; The elastomeric body (1) in the elastomeric pipeline is impacted on the surface of the sample to be tested after being impacted and collided by the piston rod (10) and is finally completed.

2. The laser cladding coupon impact tester of claim 1, wherein The cylinder 3 converts air pressure into piston rod (10) thrust to complete the driving supply of the whole impact testing machine, which is a double-acting single-rod cylinder.

3. The laser cladding coupon impact tester of claim 1, wherein The elastomeric pipeline (2) is provided with a flange plate (25) on one side, and is connected and fixed with the cylinder (3) through the flange plate.

4. The laser cladding coupon impact tester of claim 1, wherein The elastomeric body (1) has three shapes, and the contact with the sample during collision is spherical contact, point contact and line contact, except for spherical contact, the tail of the elastomeric body is a cylinder to adapt to the reduction of friction in the elastomeric pipeline.

5. The laser cladding coupon impact tester of claim 1, wherein The clamp (7) includes a bolt (7-1), a clamping nut (7-2) and a pad (7-3), the bolt (7-1) is fixed on the bolt hole (22) of the base, different bolt holes are selected for samples of different sizes, the clamping nut 7-2 is tightened to fix the pad 7-3, so as to fix the sample to be tested (8).

6. The laser cladding coupon impact tester of claim 1, wherein The top end of the piston rod (10) is attached with a damping sheet (18) made of rubber.

7. The laser-clad coupon impact tester of claim 1, wherein The elastomeric pipeline (2) is a hollow steel pipe.

8. The laser-clad coupon impact tester of claim 1, wherein Three groups of evenly distributed supports (16) are arranged at the bottom of the elastomeric pipeline (2) as supports.

9. The laser-clad coupon impact tester of claim 1, wherein Protection devices (6) are arranged around the base (9) to prevent sample debris from splashing during the impact test and ensure the safety of the test.

10. The laser-clad coupon impact tester of claim 1, wherein The length of the elastomeric pipeline (2) is greater than the maximum stroke of the cylinder.

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