阅读说明：本技术 一种钛合金蒙皮-桁条壁板双激光束双侧同步焊接缺陷抑制的体系化调控方法 (Systematic regulation and control method for double-laser-beam double-side synchronous welding defect suppression of titanium alloy skin-stringer wallboard ) 是由 占小红 刘金钊 王磊磊 颜廷艳 周之鹤 于 2020-05-27 设计创作，主要内容包括：本发明涉及一种钛合金蒙皮-桁条壁板双激光束双侧同步焊接缺陷抑制的体系化调控方法。通过开展钛合金蒙皮-桁条壁板试片件双激光束双侧同步焊接实验,收集接头信息,利用RSM响应面分析法建立起工艺参数与焊缝信息、接头缺陷信息之间的统计学模型。在钛合金蒙皮-桁条壁板结构件双激光束双侧同步焊接过程中,激光过程控制系统对焊缝区域进行实时监测,捕捉的焊缝信息经处理后反馈至信息判断中心。若焊缝质量不合格,根据反馈的判定结果,调节中心进一步提出参数优化方案,焊接过程继续。优化方案的制定以试片件实验所建立的工艺参数与焊缝信息、接头缺陷信息的统计学模型为指导,最终实现了控制钛合金蒙皮桁条壁板双激光束双侧同步焊接缺陷的目的。(The invention relates to a systematic regulation and control method for double-laser-beam double-side synchronous welding defect suppression of a titanium alloy skin-stringer wallboard. By carrying out a double-laser-beam double-side synchronous welding experiment on a titanium alloy skin-stringer wallboard test piece, collecting joint information, and establishing a statistical model among process parameters, welding seam information and joint defect information by using an RSM response surface analysis method. In the double-laser-beam double-side synchronous welding process of the titanium alloy skin-stringer wall plate structural part, the laser process control system monitors the welding line area in real time, and captured welding line information is processed and then fed back to the information judgment center. If the quality of the welding seam is unqualified, according to the fed back judgment result, the adjusting center further provides a parameter optimization scheme, and the welding process is continued. The establishment of the optimization scheme is guided by a statistical model of process parameters, welding seam information and joint defect information established by a test piece experiment, and finally the purpose of controlling double-laser-beam double-side synchronous welding defects of the titanium alloy skin-stringer wallboard is achieved.)

1. A systematic regulation and control method for inhibiting double-laser-beam double-side synchronous welding defects of a titanium alloy skin-stringer wallboard is characterized by comprising the following steps:

(1) the laser process control system monitors the quality of the welding seam in real time: in the actual welding process, the laser process control system monitors the welding seam quality in real time, and captures the macroscopic forming condition of the welding seam and 3D welding seam data by utilizing a sensor integrated with the laser process control system;

(2) extracting and feeding back weld joint information: based on the 3D welding seam information and the 3D joint information captured by the sensors, the global control system separates and extracts the welding seam information and the joint defect information and further feeds the welding seam information and the joint defect information back to the information judgment center;

(3) and (3) judging the quality of the welding seam: the information judgment center judges the obtained defect information, and when the weld zone has no defects such as large-size pores, incomplete fusion, welding leakage, undercut and the like, the quality of the weld is judged to be qualified, and the welding process can be continued; when the welding seam area has large-size air hole defects or welding defects such as welding leakage, incomplete fusion and the like, the quality of the welding seam can be judged to be unqualified, the welding process is terminated, and the judgment result is fed back to the adjusting center;

(4) and (3) parameter optimization scheme formulation: and the adjusting center receives the judgment result of the defect information, and when the quality of the welding seam is unqualified, the technological parameters need to be optimized and adjusted. And optimizing the welding process parameters by taking a statistical model between the process parameters established by the test piece experiment and the welding defect response as guidance. The control of the double-laser-beam double-side synchronous welding defects of the titanium alloy skin-stringer wallboard is realized by adjusting parameters such as laser power, welding speed, defocusing amount, laser incidence angle and the like.

2. The titanium alloy skin-stringer wall plate double-laser-beam double-side synchronous welding defect suppression systematic regulation and control method according to claim 1, characterized in that: a laser process control system is set up, and in the actual welding process, the laser process control system is positioned at the rear side of the laser head and is kept synchronous with the laser head, so that the real-time monitoring of the welding seam quality can be realized.

3. The titanium alloy skin-stringer wall plate double-laser-beam double-side synchronous welding defect suppression systematic regulation and control method according to claim 1, characterized in that: the laser process control system is integrated with a 3D laser sensor, a video sensor, a reflective photoelectric sensor and a temperature sensor, wherein 3D welding seam information is captured by the 3D laser sensor and the video sensor, and defect information is captured by the temperature sensor and the reflective photoelectric sensor. All information is fed back to the information judgment center in the form of electric signals.

4. The titanium alloy skin-stringer wall plate double-laser-beam double-side synchronous welding defect suppression systematic regulation and control method according to claim 1, characterized in that: the weld joint information captured by the sensor is transmitted to the global control system, the 3D weld joint information and the defect information are extracted and separated through a self-contained algorithm of the system, whether the defects of welding leakage, incomplete welding, undercut, overlarge surface roughness and the like exist or not is judged based on the 3D weld joint information, the defect information is analyzed, and whether the defects of large-size air holes and the like exist or not is judged.

5. The titanium alloy skin-stringer wall plate double-laser-beam double-side synchronous welding defect suppression systematic regulation and control method according to claim 1, characterized in that: the method comprises the steps of designing an experimental scheme by adopting a Central Composite Design (CCD), carrying out a double-laser-beam bilateral synchronous welding experiment on a titanium alloy skin-stringer wallboard test piece, and acquiring welding seam information and joint defect data under different process parameters by means of metallographic observation and the like after welding. And summarizing the obtained welding seam information and joint defect data, wherein the welding seam information comprises porosity S, fusion depth D (mm) and welding seam width W (mm). The process parameters (laser power P (W), welding speed v (mm/S), laser incidence angle A (degree) and defocusing amount f) are used as input parameters, welding joint information and defect data (porosity S, penetration D and weld width W) are used as output responses, and a statistical model among the process parameters, the weld information and the joint defect information is established by adopting an RSM (stress surface method) response surface analysis method. On the basis of the model, the independent action and the interaction of each process parameter can be well analyzed, and the process parameters are subjected to targeted optimization adjustment aiming at the feedback defect information, so that a perfect parameter optimization scheme is worked out.

Technical Field

The invention relates to the technical field of laser welding, in particular to a systematic regulation and control method for double-laser-beam double-side synchronous welding defect suppression of a titanium alloy skin-stringer wallboard, and particularly relates to a systematic control technology for a double-laser-beam double-side synchronous welding process.

Background

The titanium alloy has the unique advantages of good specific strength, specific modulus and the like, and compared with the aluminum alloy skin-stringer wallboard structure, the titanium alloy skin-stringer wallboard structure has higher reliability, and simultaneously meets the requirement of an aircraft on light weight, and the titanium alloy skin-stringer wallboard structure is more widely applied under the rapid development background of the aviation industry. The double-laser-beam double-side synchronous welding technology is a brand-new laser welding technology, can effectively relieve the deformation problem of a skin-wall plate, and also successfully avoids the damage of the traditional single-side welding double-side forming technology to the surface integrity of the skin, so the technology has great superiority. In foreign countries, the process has been implemented for use on different families of large passenger aircraft.

Because the welding process is immature, welding defects are easy to generate in the welding process. The existence of welding defects seriously affects the mechanical properties of a weldment, so that the control of the welding defects is an urgent problem to be solved all the time. The titanium alloy is very easy to absorb hydrogen and oxygen in the welding process, and if the titanium alloy is not protected properly, a large amount of air holes are formed in a welded joint area after welding. And because the current titanium alloy double-laser-beam double-side synchronous welding process is not complete and the selection of process parameters is not proper, the welding defects of incomplete fusion, incomplete penetration, cracks and the like after welding can greatly weaken the fatigue limit of a weldment, reduce the service life of the weldment, and still have certain difficulty in realizing the inhibition of the titanium alloy skin-stringer wallboard double-laser-beam double-side synchronous welding defects.

Disclosure of Invention

Aiming at the existing problems, the invention aims to provide a systematic regulation and control method for inhibiting double-laser-beam double-side synchronous welding defects of a titanium alloy skin-stringer wallboard. And (4) monitoring the welding process and the welded joint area solidified after welding in real time, separating to obtain defect information, and feeding the defect information back to the information control center for judgment. And based on the judgment result, further optimizing the process parameters, thereby realizing the control of the defects of the welding seam area.

In order to achieve the aim, the invention provides a systematic regulation and control method for inhibiting double-laser-beam double-side synchronous welding defects of a titanium alloy skin-stringer wallboard, which comprises the following steps:

(1) the laser process control system monitors the quality of the welding seam in real time: in the actual welding process, the laser process control system monitors the welding seam quality in real time, and captures the macroscopic forming condition of the welding seam and 3D welding seam data by utilizing a sensor integrated with the laser process control system;

(2) extracting and feeding back weld defect information: based on the 3D welding seam information and the 3D joint information captured by the sensors, the global control system separates and extracts the welding seam information and the joint defect information and further feeds the welding seam information and the joint defect information back to the information judgment center;

(3) and (3) judging the quality of the welding seam: the information judgment center judges the obtained defect information, and when the weld zone has no defects such as large-size pores, incomplete fusion, welding leakage, undercut and the like, the quality of the weld is judged to be qualified, and the welding process can be continued; when the welding seam area has large-size air hole defects or welding defects such as welding leakage, incomplete fusion and the like, the quality of the welding seam can be judged to be unqualified, the welding process is terminated, and the judgment result is fed back to the adjusting center;

(4) and (3) parameter optimization scheme formulation: and the adjusting center receives the judgment result of the defect information, and when the quality of the welding seam is unqualified, the technological parameters need to be optimized and adjusted. And optimizing the welding process parameters by taking a statistical model between the process parameters established by the test piece experiment and the welding defect response as guidance. The control of the double-laser-beam double-side synchronous welding defects of the titanium alloy skin-stringer wallboard is realized by adjusting parameters such as laser power, welding speed, defocusing amount, laser incidence angle and the like.

Furthermore, a laser process control system is set up, and in the actual welding process, the laser process control system is positioned on the rear side of the laser head and is kept synchronous with the laser head, so that the real-time monitoring of the welding seam quality can be realized.

Further, the laser process control system is integrated with a 3D laser sensor, a video sensor, a reflective photoelectric sensor and a temperature sensor, wherein 3D welding seam information is captured by the 3D laser sensor and the video sensor, and defect information is captured by the temperature sensor and the reflective photoelectric sensor. All information is fed back to the information judgment center in the form of electric signals.

Further, weld joint information captured by the sensor is transmitted to the global control system, the 3D weld joint information and defect information are extracted and separated through a self-contained algorithm of the system, whether defects such as welding leakage, incomplete penetration, undercut and overlarge surface roughness occur or not is judged based on the 3D weld joint information, the defect information is analyzed, and whether defects such as large-size air holes exist or not is judged.

Further, a Central Composite Design (CCD) is adopted to carry out experimental scheme Design, a double-laser-beam bilateral synchronous welding experiment of the titanium alloy skin-stringer wallboard test piece is carried out, and after welding, welding seam information and joint defect data under different process parameters are acquired by means of metallographic observation and the like. And summarizing the obtained welding seam information and joint defect data, wherein the welding seam information comprises porosity S, fusion depth D (mm) and welding seam width W (mm). The process parameters (laser power P (W), welding speed v (mm/S), laser incidence angle A (degree) and defocusing amount f) are used as input parameters, welding joint information and defect data (porosity S, penetration D and weld width W) are used as output responses, and a statistical model among the process parameters, the weld information and the joint defect information is established by adopting an RSM (stress Surface method) response Surface analysis method. On the basis of the model, the independent action and the interaction of each process parameter can be well analyzed, and the process parameters are subjected to targeted optimization adjustment aiming at the feedback defect information, so that a perfect parameter optimization scheme is worked out.

The invention has the beneficial effects that: due to the immaturity of the welding process and the improper selection of the process parameters, various welding defects such as welding leakage, incomplete welding, large-size air holes and the like are easy to occur in the double-laser-beam double-side synchronous welding process of the titanium alloy. The built laser process control system and the laser head move synchronously, and the real-time monitoring of the welding seam quality can be realized by utilizing the sensor integrated inside. And after the welding seam information is processed by the global control system and the information judgment center, the judgment result is fed back to the regulation center, and then a corresponding parameter optimization scheme is worked out, so that the aim of inhibiting double-laser-beam double-side synchronous welding defects of the titanium alloy skin-stringer wallboard in real time is fulfilled.

Drawings

FIG. 1 is a flow chart of a systematic regulation and control method for double-laser-beam double-side synchronous welding defect suppression according to the present invention;

FIG. 2 is a flow chart of a statistical model between process parameters and welding defects established by the RSM response surface analysis method of the present invention;

FIG. 3 is a schematic diagram of double-laser-beam double-side synchronous welding of the titanium alloy skin-stringer wall plate according to the present invention;

the method comprises the following steps of 1-covering, 2-laser head, 3-stringer, 4-welding seam, 5-laser beam and 6-laser process control system.

Detailed Description

The following is a specific description of the systematic regulation and control method for double-laser-beam double-side synchronous welding defects of the titanium alloy skin-stringer wallboard.

A test piece double-laser-beam double-side synchronous welding experiment is carried out on a TC4 titanium alloy skin-stringer wallboard, wherein the thickness of the skin is 1.2mm, the stringer is simplified into a flat plate, and the size of the flat plate is 500mm multiplied by 100mm multiplied by 2 mm. In the experiment, a TruDisk 12003 disc type laser is adopted, the maximum power is 12000W, the laser is provided with 2 optical fibers with the length of 30m and the core diameter of 1000 mu m, and the optical fibers are connected to two laser welding heads respectively, so that the double-beam laser welding process is realized.

The experimental scheme Design is carried out by adopting a Central Composite Design (CCD), and the double-laser-beam double-side synchronous welding experiment of the titanium alloy skin-stringer wallboard test piece is carried out. After the welding experiment is completed, the weldment is subjected to warp cutting to obtain a metallographic sample, the obtained sample is subjected to grinding, polishing and corrosion, joint microscopic welding defect information is collected, the joint porosity of different samples is calculated, and weld joint information including fusion depth, weld joint width and the like is measured. A RSM response surface analysis method is adopted to establish a mathematical relation between process parameters (xi, xj: laser power, welding speed, defocusing amount and protective gas flow) and weld joint information and joint defect data (Y: porosity, maximum pore size, penetration and weld joint width) response, and the basic form is as shown in formula 1:

in the formula, 0 is a random test error; β i is a first order normal coefficient; beta ij is a constant coefficient of a multi-factor interaction term; β ii is a quadratic term constant coefficient; beta 0 is a response value of the response surface design space central point.

After the model is subjected to significance test, the model has a reliable guiding effect on the formulation of a parameter scheme.

And carrying out a double-laser-beam bilateral synchronous welding experiment on the titanium alloy skin-stringer wallboard structural part, monitoring the welding seam forming condition in real time by using a laser process control system synchronous with a laser head, and feeding back the obtained 3D welding seam data and joint data to an information judgment center after the obtained 3D welding seam data and the joint data are processed by a global control system. Judging the welding seam quality by the information judgment center, judging the welding seam quality to be qualified when the welding seam position is detected to have no large-size air holes and welding defects such as welding leakage, non-fusion and the like do not occur, and continuing the welding process; when the detection result shows that the large-size air holes exist in the position of the welding seam, or the welding seam has welding defects such as welding leakage, incomplete fusion and the like, the information judgment center judges that the quality of the welding seam is unqualified, the welding process is terminated, and the judgment result is fed back to the adjustment center. Based on the statistical relationship among the process parameters, the welding seam information and the joint defect information established by the RSM response surface analysis method, the adjusting center carries out targeted optimization adjustment on the process parameters to obtain a perfect parameter optimization scheme. And reconfiguring the optimized parameters by the industrial personal computer, and continuing the welding process.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.