CN112122741A - Welding bead forming control system in electric arc additive manufacturing process and parameter optimization method thereof - Google Patents
Welding bead forming control system in electric arc additive manufacturing process and parameter optimization method thereof Download PDFInfo
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- CN112122741A CN112122741A CN202010816421.7A CN202010816421A CN112122741A CN 112122741 A CN112122741 A CN 112122741A CN 202010816421 A CN202010816421 A CN 202010816421A CN 112122741 A CN112122741 A CN 112122741A
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- additive manufacturing
- arc additive
- computer control
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- electric arc
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/04—Welding for other purposes than joining, e.g. built-up welding
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y10/00—Processes of additive manufacturing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B33—ADDITIVE MANUFACTURING TECHNOLOGY
- B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
- B33Y50/00—Data acquisition or data processing for additive manufacturing
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- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Physics & Mathematics (AREA)
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- Mechanical Engineering (AREA)
- Arc Welding In General (AREA)
- Arc Welding Control (AREA)
Abstract
The invention relates to the technical field of electric arc additive manufacturing, in particular to a welding bead forming control system in the electric arc additive manufacturing process and a parameter optimization method thereof, wherein the welding bead forming control system in the electric arc additive manufacturing process comprises a computer control module, an off-line programming module, an electric arc additive manufacturing system and a monitoring and feedback adjusting system; the off-line programming module designs a designed deposition path and then sends the deposition path to the computer control module; the electric arc additive manufacturing system welds and processes the parts according to the deposition path; the monitoring and feedback adjusting system monitors the temperature of the molten pool; the computer control module controls the welding processing of the arc material increase manufacturing system according to the off-line programming module and the data fed back by the monitoring and feedback system.
Description
Technical Field
The invention relates to the technical field of electric arc additive manufacturing, in particular to a welding bead forming control system in an electric arc additive manufacturing process and a parameter optimization method thereof.
Background
The metal arc additive manufacturing technology is characterized in that an electric arc is used as a heat source, a target part material is melted, and then a layer-by-layer stacking mode is adopted to obtain a target part. Compared with the traditional manufacturing process, the manufacturing process has the advantages of short manufacturing period, high flexibility, easy realization of digital, intelligent and parallel manufacturing, and suitability for small-batch production. The method has the advantages of high material utilization rate, low cost, low pollution and the like. The method is applied to the high-precision fields of aerospace, national defense military industry and the like.
However, the electric arc additive manufacturing is a complex metal micro-smelting process, the temperature and the welding state of the electric arc additive manufacturing are constantly changed, the shape of the formed part is difficult to control due to the instability of a molten pool in the additive manufacturing process, so that the stress of the internal structure after forming is more concentrated, and the shape and the size of the formed part are greatly influenced, so that the negative feedback control in the forming process is very important.
Disclosure of Invention
The invention aims to provide a weld bead forming control system in an electric arc additive manufacturing process and a parameter optimization method thereof, which can effectively reduce the change of a molten pool, improve the stability in a cladding process and effectively optimize process parameters in a welding process through continuous feedback adjustment.
In order to achieve the purpose, the invention provides the following technical scheme: a welding bead forming control system in an electric arc additive manufacturing process comprises a computer control module, an off-line programming module, an electric arc additive manufacturing system and a monitoring and feedback adjusting system;
the off-line programming module is provided with drawing design software and path planning software, the drawing design software is introduced into the path planning software after a part model is designed, and the path planning software is sent to the computer control module after a deposition path is designed;
the arc additive manufacturing system welds the machined part according to a deposition path provided by the computer control module;
the monitoring and feedback adjusting system monitors the temperature of the molten pool and feeds the temperature back to the computer control module;
the computer control module is respectively connected with the off-line programming module, the electric arc additive manufacturing system and the monitoring and feedback system, and the computer control mechanical arm controls the welding processing of the electric arc additive manufacturing system according to the off-line programming module and data fed back by the monitoring and feedback system.
Preferably, electric arc vibration material disk system includes welding mechanism, arm, mechanical arm switch board and wire feeding mechanism, welding mechanism and wire feeding mechanism install on the arm, the arm is controlled by the mechanical arm switch board, the mechanical arm switch board is connected with computer control module electricity.
Preferably, the monitoring and feedback adjusting system comprises an industrial camera, a temperature sensor and an optical filter, the industrial camera shoots the appearance of the molten pool through the optical filter, and the temperature sensor records the temperature of the molten pool and transmits the temperature to the computer control module.
Preferably, the industrial camera is mounted on a robotic arm.
Preferably, the off-line programming module designs the planned path to drive a robot arm in the arc additive manufacturing system by converting the planned path into program code through a D/A (digital/analog) converter.
A parameter optimization method of a weld bead forming control system in an electric arc additive manufacturing process comprises the following steps:
a. the off-line programming module is used for off-line programming, the drawing design software is used for importing path planning software after designing a part model, and the path planning software is used for designing a deposition path and then sending the deposition path to the computer control module;
b. the arc additive manufacturing system welds the machined part according to the deposition path received by the computer control module;
c. the monitoring and feedback adjusting system monitors the temperature of the molten pool and feeds the temperature back to the computer control module;
d. the computer control module judges whether the appearance of the molten pool meets the requirement according to the picture transmitted by the monitoring and feedback adjusting system, and if the appearance of the molten pool does not meet the requirement, a feedback signal is given to adjust a mechanical arm in the arc additive manufacturing system;
e. and judging the appearance of the part after the welding process is finished, observing the temperature change of the molten pool, and recording process parameters if the temperature change meets the requirements.
Compared with the prior art, the invention has the beneficial effects that: compared with the traditional casting and forging manufacturing process, the electric arc additive manufacturing technology has the advantages of high forming rate, high material utilization rate, low equipment cost, no need of a die, short manufacturing period of the system, higher flexibility and capability of realizing digitization and intellectualization; the invention solves the problem of unstable molten pool in the process of electric arc additive manufacturing, and improves the forming precision of a formed part; the system is simple, the technical means is simple, and the method has substantial progress in promoting the development of the electric arc additive manufacturing.
Drawings
Fig. 1 is a flowchart of a weld bead shaping control system in an arc additive manufacturing process according to the present invention;
fig. 2 is a flowchart illustrating operation of a bead shaping control system in an arc additive manufacturing process according to the present invention;
fig. 3 is a flowchart illustrating the operation of a monitoring and feedback adjusting system in a bead forming control system in an arc additive manufacturing process according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1-3, the present invention provides a technical solution: a welding bead forming control system in an electric arc additive manufacturing process comprises a computer control module, an off-line programming module, an electric arc additive manufacturing system and a monitoring and feedback adjusting system, the off-line programming module is provided with drawing design software and path planning software, the drawing design software is used for designing a part model and then importing the part model into the path planning software, the path planning software is used for designing a deposition path and then sending the deposition path to the computer control module, the arc additive manufacturing system welds and processes parts according to the deposition path provided by the computer control module, the monitoring and feedback adjusting system monitors the temperature of a molten pool and feeds the temperature back to the computer control module, the computer control module is respectively connected with the off-line programming module, the arc additive manufacturing system and the monitoring and feedback system, and the computer control mechanical arm controls the welding and processing of the arc additive manufacturing system according to data fed back by the off-line programming module and. Specifically, in this embodiment, the drawing design software is CAD drawing software, the CAD drawing software draws a model of a part to be manufactured, stores the model, and then introduces path planning software, and then performs slicing and path simulation on the model, where the slice thickness is a weld bead height, the weld width is a single layer width, and the parameter is a parameter obtained by welding on the welding carriage. And after the path is drawn, inputting parameters such as welding speed, wire feeding speed, height of a welding gun from the substrate and the like to obtain a control instruction stream of the arc additive manufacturing system. Further, the electric arc additive manufacturing system comprises a welding mechanism, a mechanical arm control cabinet and a wire feeding mechanism, wherein the welding mechanism and the wire feeding mechanism are installed on the mechanical arm, the mechanical arm is controlled by the mechanical arm control cabinet, the mechanical arm control cabinet is electrically connected with the computer control module, the welding mechanism comprises a TIG welding machine, a TIG welding gun, a welding gun clamp and a welding workbench, the TIG welding machine generates electric arcs, the TIG welding gun melts wires through a heat source and then deposits the wires layer by layer according to a planned path, and a complete metal part in a required shape is obtained.
Preferably, the monitoring and feedback adjusting system comprises an industrial camera, a temperature sensor and an optical filter, the industrial camera shoots the appearance of the molten pool through the optical filter, the temperature sensor records the temperature of the molten pool and transmits the temperature to the computer control module, wherein the industrial camera and the temperature sensor are both arranged at the tail end of the mechanical arm and move along with the mechanical arm, real-time seam tracking can be realized, the temperature sensor feeds the detected temperature of the surface of the part back to the computer control system for recording, and the change of the temperature can be visually seen. The industrial camera shoots the appearance of the molten pool through the optical filter, each picture is transmitted back to the computer, the image is subjected to gray processing and binarization processing through Matlab, the size of the molten pool is calculated, and after the size of the molten pool is compared with a preset value, if the deviation exceeds 10%, an adjusting signal is fed back, technological parameters such as the height of a mechanical arm, the welding speed and the like are adjusted, and the forming precision of a formed part is continuously improved. The temperature change data recorded by the computer and the molten pool feedback signal are used for continuously optimizing the process parameters, which is beneficial to parameter setting of subsequent path planning, further reduces the adjusting times in the deposition process and is beneficial to improving the forming quality.
Preferably, the off-line programming module designs the planned path to drive a robot arm in the arc additive manufacturing system by converting the planned path into program code via D/a.
The application also provides a parameter optimization method of the welding bead forming control system in the electric arc additive manufacturing process, which comprises the following steps:
a. off-line programming of an off-line programming module, wherein after a part model is designed by drawing design software (CAD, Creo, UG, Solidworks and the like), path planning software is introduced (an AM Slice in Master CAM: Wire/Arc module is selected by the system), a deposition path is designed by the path planning software and then is sent to a computer control module, technological parameters such as welding speed, welding gun height, interlayer height, Wire feeding speed and the like are set, a simulation path is generated, a code of a corresponding mechanical arm model is output, the simulation path is introduced into a control cabinet of the mechanical arm, and then an off-line programming part is completed;
b. the arc additive manufacturing system welds the machined part according to the deposition path received by the computer control module; specifically, a substrate (200mm × 200mm × 20mm) is placed on a workbench, a TIG welding gun is connected with the TIG welding machine, argon with the purity of 99.9% is used as shielding gas, the gas flow is 15l/min, external wire feeding is carried out, the wire feeding speed is 200cm/min, the included angle between a wire and the substrate is 30 degrees, the welding current is 180A, the arc length is 5mm, and a mechanical arm control cabinet controls a mechanical arm to drive the welding gun to operate according to a preset track;
c. the monitoring and feedback adjusting system monitors the temperature of the molten pool and feeds the temperature back to the computer control module; specifically, the temperature sensor transmits the detected temperature back to the computer control system, and records the temperature, and the change of the temperature in the deposition process can be drawn at the later stage.
d. The computer control module judges whether the appearance of the molten pool meets the requirement according to the picture transmitted by the monitoring and feedback adjusting system, and if the appearance of the molten pool does not meet the requirement, a feedback signal is given to adjust a mechanical arm in the arc additive manufacturing system; specifically, the industrial camera accurately shoots the appearance of the molten pool through the optical filter and transmits the appearance of the molten pool back to the computer, the image processing software is used for processing and judging whether the requirement is met, and if the requirement is not met, a feedback signal is given to adjust the mechanical arm. Each picture is transmitted back to the computer, the image is subjected to gray processing and binarization processing through Matlab, the size of a molten pool is calculated, and after the size of the molten pool is compared with a preset value, if the deviation reaches 5%, an adjusting signal is fed back, and technological parameters such as the height of the mechanical arm and the welding speed are adjusted;
e. and judging the appearance of the part after the welding process is finished, observing the temperature change of the molten pool, and recording the process parameters after each adjustment if the temperature change meets the requirements so as to facilitate the setting of the process parameters at the later stage.
According to the welding bead forming control system and the parameter optimization method thereof in the electric arc additive manufacturing process, the welding bead molten pool is calculated and adjusted through model drawing, path planning and a monitoring feedback system, quantitative control over the molten pool is achieved, and therefore forming precision of parts is improved; the recording of the temperature and the feedback process is helpful for adjusting the process parameters. Has great practical value and wide application prospect for the application of industrial production.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (6)
1. A welding bead forming control system in an electric arc additive manufacturing process is characterized by comprising a computer control module, an off-line programming module, an electric arc additive manufacturing system and a monitoring and feedback adjusting system;
the off-line programming module is provided with drawing design software and path planning software, the drawing design software is introduced into the path planning software after a part model is designed, and the path planning software is sent to the computer control module after a deposition path is designed;
the arc additive manufacturing system welds the machined part according to a deposition path provided by the computer control module;
the monitoring and feedback adjusting system monitors the temperature of the molten pool and feeds the temperature back to the computer control module;
the computer control module is respectively connected with the off-line programming module, the electric arc additive manufacturing system and the monitoring and feedback system, and the computer control mechanical arm controls the welding processing of the electric arc additive manufacturing system according to the off-line programming module and data fed back by the monitoring and feedback system.
2. The system of claim 1, wherein the system comprises a welding mechanism, a robot arm control cabinet and a wire feeder, the welding mechanism and the wire feeder are mounted on the robot arm, the robot arm is controlled by the robot arm control cabinet, and the robot arm control cabinet is electrically connected to the computer control module.
3. The system of claim 2, wherein the monitoring and feedback control system comprises an industrial camera, a temperature sensor and an optical filter, the industrial camera captures the molten pool appearance through the optical filter, and the temperature sensor records the molten pool temperature and transmits the molten pool temperature to the computer control module.
4. The weld bead shaping control system in an arc additive manufacturing process according to claim 3, wherein the industrial camera is mounted on a robotic arm.
5. The system of claim 1, wherein the off-line programming module is configured to convert the planned path into programming code via D/A to drive a robotic arm in the arc additive manufacturing system.
6. The method for optimizing parameters of a bead shaping control system in an arc additive manufacturing process according to any one of claims 1 to 5, comprising the steps of:
a. the off-line programming module is used for off-line programming, the drawing design software is used for importing path planning software after designing a part model, and the path planning software is used for designing a deposition path and then sending the deposition path to the computer control module;
b. the arc additive manufacturing system welds the machined part according to the deposition path received by the computer control module;
c. the monitoring and feedback adjusting system monitors the temperature of the molten pool and feeds the temperature back to the computer control module;
d. the computer control module judges whether the appearance of the molten pool meets the requirement according to the picture transmitted by the monitoring and feedback adjusting system, and if the appearance of the molten pool does not meet the requirement, a feedback signal is given to adjust a mechanical arm in the arc additive manufacturing system;
e. and judging the appearance of the part after the welding process is finished, observing the temperature change of the molten pool, and recording process parameters if the temperature change meets the requirements.
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Application publication date: 20201225 |