A supersonic laser deposition powder collection device with safety monitoring

Abstract

A supersonic laser deposition powder collection device with safety monitoring includes a powder feeder and a laser, a nozzle and a power supply, the nozzle is arranged in the through hole of a metal shielding plate, a workbench is arranged below the metal shielding plate, the nozzle is aimed at the substrate on the workbench, and a powder collection box is arranged below the workbench; the upper end of the outer aramid fiber cloth is enclosed outside the metal shielding plate, the lower end of the outer aramid fiber cloth is connected to the outer wall of the powder collection box, the upper end of the inner aramid fiber cloth is connected to the outer side of the workbench, and the lower end of the outer aramid fiber cloth is connected to the inner wall of the powder collection box; the metal shielding plate, the workbench, the outer aramid fiber cloth, the inner aramid fiber cloth, and the powder collection box are enclosed to form a closed space; the exhaust fan is arranged in the sealed space, the exhaust fan air inlet is equipped with a filter screen, and the side wall of the exhaust fan air inlet is sealed and connected to the outer aramid fiber cloth. The beneficial effects of the present invention are: automatically collecting powder sprayed into the air; preventing dust explosion.

Description

Technical Field

[0001] The invention belongs to the field of supersonic laser deposition, and in particular relates to a supersonic laser deposition powder collecting device with safety monitoring. Background Art

[0002] Supersonic laser deposition (SLD) technology is a new type of laser composite manufacturing technology developed in recent years. In this technology, high-pressure airflow (compressed air or nitrogen) is divided into two paths: one path carries the spray particles into the mixing chamber through the powder feeder, and the other path is preheated by the gas heater, and then fully mixed with the airflow carrying the spray particles in the mixing chamber to form a gas-solid two-phase flow. The mixed gas-solid two-phase flow enters the Laval nozzle for acceleration, and the spray particles hit the surface of the substrate heated synchronously by the laser at supersonic speed to form a deposition layer. The laser head is at a certain angle to the normal line of the substrate surface or is arranged coaxially with the nozzle. The Laval nozzle is perpendicular to the substrate surface, and the laser beam and the spray powder will partially overlap. Therefore, the laser can not only heat the substrate surface area, but also preheat the spray powder, which can soften both. In the process of supersonic laser deposition, the powder particles and high-pressure gas reach supersonic speed, which is extremely dangerous to the human body. The deposition temperature of the spraying area can be monitored in real time by an infrared pyrometer, and the output power of the laser can be adjusted in real time by a closed-loop feedback system to ensure that the deposition temperature is constant during the preparation of the deposition layer.

[0003] Most of the current supersonic laser deposition technology is carried out in a special spraying room without a special powder collection device. The door will be closed during the deposition process, and personnel will enter to clean the room after the deposition experiment is completed. Although this method improves safety, it has the following disadvantages:

[0004] 1. The speed of the sprayed powder particles is extremely high. After colliding with the substrate, the undeposited powder particles will be reflected, causing the entire spray room to be full of powder, which is not conducive to cleaning. Moreover, since the sprayed particles are very small, they may be suspended in the air and inhaled by people, causing harm.

[0005] 2. A lot of dust on the ground is mixed into the powder particles after cleaning, which makes the powder particles unable to be reused. The powder is expensive, which wastes resources and increases processing costs.

[0006] 3. There is no real-time monitoring device for dust concentration in the existing supersonic laser deposition room, nor is there an alarm or emergency stop setting for powder concentration. When the spraying powder contains explosive metals such as Mg and Al, and the powder concentration and temperature reach a certain value, dust explosion may occur.

[0007] 4. The existing supersonic laser deposition room does not have an automatic emergency stop function when an abnormality is detected, and cannot prevent the occurrence of danger in time.

[0008] Aramid fiber is a new type of high-tech synthetic fiber with excellent properties such as ultra-high strength, high modulus, high temperature resistance, acid and alkali resistance, and light weight. Its strength is 5 to 6 times that of steel wire, its modulus is 2 to 3 times that of steel wire or glass fiber, its toughness is 2 times that of steel wire, and its weight is only about 1 / 5 of that of steel wire. It does not decompose or melt at a temperature of 560 degrees. It has good insulation and anti-aging properties, a long life cycle, and good high temperature resistance. The continuous use temperature range of aramid 1414 is extremely wide, and it can operate normally for a long time in the range of -196℃ to 204℃. The shrinkage rate is 0 at 150℃, it does not decompose or melt at a high temperature of 560℃, and it has good insulation and corrosion resistance, and a long life cycle, so it has won the reputation of "synthetic steel wire". Aramid 1414 was first used in cutting-edge fields such as national defense and military industry. Aramid 1414 is widely used in bulletproof vests, bulletproof helmets, stab and cut resistant clothing, explosive disposal clothing, high-strength parachutes, bulletproof car bodies, armor plates, etc. In bulletproof vests, due to the high strength, toughness and good weaving properties of aramid fibers, it can absorb the energy of bullet impact and disperse it to other fibers of the woven fabric to avoid "blunt injuries", thus providing significant protection. The lightweight of aramid bulletproof vests and helmets has effectively improved the army's rapid response and protection capabilities. Summary of the invention

[0009] In order to solve the above-mentioned technical problems, the purpose of the present invention is to provide a supersonic laser deposition powder collection device with safety monitoring, which can reduce the cleaning workload and improve production efficiency, recycle powder to reduce production costs, prevent dust from flying and injuring the human body, and monitor dust concentration and spot temperature in real time to prevent explosion accidents. Its alarm emergency stop system can take timely measures to stop the machine from working to prevent accidents.

[0010] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0011] A supersonic laser deposition powder collection device with safety monitoring, characterized in that it includes a powder feeder, a laser, a nozzle and a power supply, characterized in that the nozzle is arranged in a through hole of a metal shielding plate, a workbench is arranged below the metal shielding plate, the nozzle is aimed at a substrate on the workbench, and a powder collection box is arranged below the workbench; the upper end of the outer aramid fiber cloth is enclosed on the outer side of the metal shielding plate, the lower end of the outer aramid fiber cloth is connected to the outer side wall of the powder collection box, the upper end of the inner aramid fiber cloth is connected to the outer side of the workbench, and the lower end of the outer aramid fiber cloth is connected to the inner side wall of the powder collection box; the metal A shielding plate, a workbench, an outer aramid fiber cloth, an inner aramid fiber cloth, and a powder collection box are enclosed to form a closed space; an air inlet of the exhaust fan passes through the outer aramid fiber cloth and is arranged in the sealed space, a filter is installed at the air inlet of the exhaust fan, and the side wall of the air inlet of the exhaust fan is sealed and connected with the outer aramid fiber cloth; an infrared thermometer and a powder concentration sensor are arranged on the workbench, and the infrared thermometer is aligned with the substrate; the infrared thermometer and the powder concentration sensor are connected to the controller through a data cable; the control ends of the powder feeder, the laser, the nozzle, and the exhaust fan are all connected to the command output end of the controller.

[0012] The exhaust fan comprises a first exhaust fan and a second exhaust fan which are arranged along the radial direction of the outer aramid fiber cloth.

[0013] The two metal shielding plates are plugged in through grooves and fastened by bolts, and the metal shielding plates are both made of lightweight and high-strength hardness materials.

[0014] All aramid fiber cloths are made of aramid, and a filter layer made of ultra-fine synthetic fiber is distributed on the outer side of the aramid fiber cloth, which is composed of nylon fiber. The combination of the two forms a good ventilation effect and a good effect of blocking powder particles.

[0015] The powder collection box is fixed to the ground during operation to prevent it from jumping when the spraying air pressure is too high.

[0016] The outer aramid fiber cloth, the inner aramid fiber cloth and other components are connected by hook and loop fasteners and fastening bolts.

[0017] The working temperature and working environment of the infrared thermometer and powder concentration sensor used can adapt to the working environment. The installation position of the powder concentration sensor is reasonably arranged after calculation to ensure that it is not irradiated by the laser reflection and is far away from the spraying area. The entire control system adopts closed-loop control.

[0018] The installation position of the powder concentration sensor ensures that it is not irradiated by the laser after reflection and is far away from the spraying area.

[0019] The aramid fiber cloth is made of aramid 1414.

[0020] The exhaust fan is tightly connected to the connection point of the aramid fiber cloth.

[0021] During the supersonic laser deposition process, the powder and the laser beam will be reflected into the air after colliding with the substrate. When the reflected powder and the laser beam collide with the top metal shielding plate and the surrounding aramid fiber cloth, a large part of the kinetic energy will be lost, and the powder will slowly fall and deposit in the powder collection box. In order to accelerate the falling of the powder particles, a symmetrically distributed exhaust fan is set; when the spraying powder particles contain explosive metal powders such as (Mg, Ti, Al), and the powder particles reach a certain concentration and encounter high temperature, an explosion may occur. Therefore, an infrared thermometer is set at the powder and laser beam to monitor the temperature in real time, and a powder concentration sensor is installed on the workbench to monitor the powder concentration in real time. When the dust concentration and the spot temperature all reach the set safety threshold, the controller will receive this signal and send a control signal instruction to the powder feeder, laser, nozzle device and alarm light. At this time, the powder feeder, laser and nozzle device all stop operating, and the alarm light flashes and sounds, and the control system is closed-loop controlled, thereby achieving the purpose of preventing dust explosions and ensuring the safety of life and property.

[0022] The beneficial effects of the invention are: the powder sprayed into the air can be automatically collected; and the purpose of dust explosion is prevented. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural diagram of the present invention. DETAILED DESCRIPTION

[0024] The specific implementation modes of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0025] Embodiment 1 A supersonic laser deposition powder collection device with safety monitoring described in the present invention comprises a powder feeder and a laser, a nozzle 5 and a power supply 1, wherein the nozzle 5 is arranged in a through hole of a metal shielding plate 3, a workbench 20 is arranged below the metal shielding plate 3, the nozzle 5 is aligned with a substrate 12 on the workbench 20, and a powder collection box 17 is arranged below the workbench 20; the upper end of the outer aramid fiber cloth 9 is enclosed on the outer side of the metal shielding plate 3, the lower end of the outer aramid fiber cloth 9 is connected to the outer side wall of the powder collection box 17, the upper end of the inner aramid fiber cloth 18 is connected to the outer side of the workbench 20, and the lower end of the outer aramid fiber cloth 18 is connected to the inner side wall of the powder collection box 17; the metal The shielding plate 3, the workbench 20, the outer aramid fiber cloth 9, the inner aramid fiber cloth 18, and the powder collection box 17 enclose a closed space; the air inlet of the exhaust fan passes through the outer aramid fiber cloth 9 and is arranged in the sealed space, the air inlet of the exhaust fan is equipped with a filter 14, and the side wall of the air inlet of the exhaust fan is sealed and connected to the outer aramid fiber cloth 9; an infrared thermometer 10 and a powder concentration sensor 21 are provided on the workbench, and the infrared thermometer 10 is aligned with the substrate 12; the infrared thermometer 10 and the powder concentration sensor 21 are connected to the controller 2 through a data cable; the control ends of the powder feeder, the laser, the nozzle 5, and the exhaust fan are all connected to the command output end of the controller 2.

[0026] The exhaust fan includes a first exhaust fan 15 and a second exhaust fan 22 which are arranged along the radial direction of the outer aramid fiber cloth 9 .

[0027] The two metal shielding plates 3 are connected by slots 6 and fastened by bolts 7. The metal shielding plates are made of lightweight and high-strength materials.

[0028] All aramid fiber cloths are made of aramid 1414, and a filter layer made of ultra-fine synthetic fiber is distributed on the outer side of the aramid fiber cloth, which is composed of nylon fiber. The combination of the two forms a good ventilation effect and a good effect of blocking powder particles.

[0029] The powder collecting box 17 is fixed on the ground during operation to prevent it from jumping when the spraying air pressure is too high.

[0030] The outer aramid fiber cloth 9, the inner aramid fiber cloth 18 and other components are connected by Velcro 19 and fastening bolts.

[0031] The working temperature and working environment of the infrared thermometer 10 and the powder concentration sensor 21 used can adapt to the working environment. The installation position of the powder concentration sensor 21 is reasonably arranged after calculation to ensure that it is not irradiated by the laser reflection and is far away from the spraying area. The entire control system adopts closed-loop control.

[0032] The installation position of the powder concentration sensor ensures that it is not irradiated by the laser after reflection and is far away from the spraying area.

[0033] The exhaust fan is tightly connected to the connection point of the aramid fiber cloth.

[0034] Embodiment 2:

[0035] like Figure 1 A supersonic laser deposition powder collection device shown includes a metal baffle plate 3, a powder collection box 17, a workbench 20, an outer aramid fiber cloth 9, an inner aramid fiber cloth 18, a metal baffle plate mounting groove 4 outside the nozzle, bolts 7, bolts 8 connecting the metal baffle plate and the aramid fiber cloth, bolts 13 connecting the aramid fiber cloth and the workbench, bolts 16 connecting the aramid fiber cloth and the powder collection box, Velcro 19, a first exhaust fan 15, a second exhaust fan 22, an infrared thermometer 10, a powder concentration sensor 21, a controller 2, a power supply 1, and an alarm light 23. The metal shielding plate 3 is divided into two parts, and its edge is provided with a groove 6 that can be inserted into the metal shielding plate mounting groove 4 outside the nozzle, and is fixed by bolts 7, so that the nozzle is centered. The outer aramid fiber cloth 9 surrounds the outer edge of the metal shielding plate and the powder collection box 17, and is fixed to each other by the metal shielding plate and aramid fiber cloth connecting bolts 8 and the aramid fiber cloth and powder collection box connecting bolts 16 respectively; fixed well, and at the same time, to ensure a good collection effect, the inner aramid fiber cloth 18 is used to form a shielding surface between the workbench 20 and the powder collection box 17, and the two are connected to each other by the aramid fiber cloth and the workbench connecting bolts 13. An infrared thermometer 10 is installed outside the nozzle 5 to monitor the temperature of the powder and the laser beam 11 spot in real time, and a powder concentration sensor 21 is installed on the workbench 20. All control signals are sent by the controller 2. The first exhaust fan 15 and the second exhaust fan 22 are installed on both sides of the workbench, and a filter screen 14 is provided at the exhaust fan port. Thus, the cleaning workload and difficulty of the spray room are greatly reduced, and the body of the workers is protected from being injured by the powder particles. The metal shielding plate 3, the outer aramid fiber cloth 9, the inner aramid fiber cloth 18, the powder collecting box 17 and the powder concentration sensor 21 are all detachable.

[0036] When the powder and laser beam 11 ejected from the nozzle 5 contain explosive metal powders such as (Mg, Ti, Al), the powder and laser beam 11 will collide with the substrate 12 and then be reflected into the air. When the reflected powder collides with the top metal shielding plate 3 and the outer aramid fiber cloth 9 around, a large part of the kinetic energy will be lost, and the particles of powder will slowly fall and be deposited in the powder collection box 17. In order to accelerate the falling of the powder particles, a symmetrically distributed first exhaust fan 15 and a second exhaust fan 22 are provided. At the same time, an infrared thermometer 10 is provided at the powder and laser beam to monitor the temperature in real time, and a powder concentration sensor 21 is installed on the workbench 20 to monitor the powder concentration in real time. When the dust concentration and the spot temperature all reach the set safety threshold, the controller 2 will receive this signal and send a control signal instruction to the powder feeder, laser, nozzle 5 and alarm light 23. At this time, the powder feeder, laser and nozzle 5 all stop operating, and the alarm light 23 flashes and beeps to send a signal, and the control system is closed-loop controlled, thereby achieving the purpose of preventing dust explosions and ensuring the safety of life and property. When an experiment is completed, the components are disassembled from top to bottom, the workbench is cleaned, and the collected powder particles are saved for next use. All aramid fiber cloths can be cleaned after being used for a period of time, and each monitoring equipment is also repaired and inspected in a timely manner.

[0037] It should be emphasized that the above are only preferred embodiments of the present invention and do not impose any form of limitation on the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A supersonic laser deposition powder collection device with safety monitoring, comprising a powder feeder and a laser, a nozzle and a power supply, characterized in that: The nozzle is arranged in the through hole of the metal shielding plate, a workbench is arranged below the metal shielding plate, the nozzle is aimed at the substrate on the workbench, and a powder collection box is arranged below the workbench; the upper end of the outer aramid fiber cloth is enclosed on the outer side of the metal shielding plate, the lower end of the outer aramid fiber cloth is connected to the outer side wall of the powder collection box, the upper end of the inner aramid fiber cloth is connected to the outer side of the workbench, and the lower end of the outer aramid fiber cloth is connected to the inner side wall of the powder collection box; the metal shielding plate, the workbench, the outer aramid fiber cloth, the inner aramid fiber cloth, and the powder collection box enclose a closed space; the air inlet of the exhaust fan passes through the outer aramid fiber cloth and is arranged in the closed space, the air inlet of the exhaust fan is equipped with a filter, and the side wall of the air inlet of the exhaust fan is sealed and connected to the outer aramid fiber cloth; an infrared thermometer and a powder concentration sensor are arranged on the workbench, and the infrared thermometer is aimed at the substrate; the infrared thermometer and the powder concentration sensor are both connected to the controller through a data line; the control ends of the powder feeder, the laser, the nozzle, and the exhaust fan are all connected to the command output end of the controller.

2. The supersonic laser deposition powder collection device with safety monitoring as claimed in claim 1, characterized in that: The exhaust fan comprises a first exhaust fan and a second exhaust fan which are arranged along the radial direction of the outer aramid fiber cloth.

3. A supersonic laser deposition powder collection device with safety monitoring according to claim 1, characterized in that: The two metal shielding plates are plugged into each other through a groove and fastened by bolts.

4. A supersonic laser deposition powder collection device with safety monitoring according to claim 1, characterized in that: All aramid fiber cloths are made of aramid, and a filter layer made of ultra-fine synthetic fiber is distributed on the outer side of the aramid fiber cloth, which is composed of nylon fiber. The combination of the two forms a good ventilation effect and a good effect of blocking powder particles.

5. A supersonic laser deposition powder collection device with safety monitoring according to claim 1, characterized in that: The powder collection box is fixed to the ground during operation.

6. A supersonic laser deposition powder collection device with safety monitoring according to claim 1, characterized in that: The outer aramid fiber cloth, the inner aramid fiber cloth and other components are connected by hook and loop fasteners and fastening bolts.

7. The supersonic laser deposition powder collection device with safety monitoring according to claim 1, characterized in that: The working temperature and working environment of the infrared thermometer and powder concentration sensor used are adapted to the working environment. The installation position of the powder concentration sensor is reasonably arranged after calculation to ensure that it is not irradiated by the laser reflection and is away from the spraying area. The entire control system adopts closed-loop control.

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