2022年, 第31卷, 第3期 
刊出日期:2022-11-26
  

  • 全选
    |
  • 韩策, 张乾, 史清宇, 唐天祥, 刘新, 张弓, 陈高强
    中国焊接. 2022, 31(3): 1-7. https://doi.org/10.12073/j.cw.20220618001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    In this paper, a new storage method for the three-dimensional temperature field data based on artificial neural network (ANN)was proposed. A multilayer perceptron that takes the coordinate $ (x,y,z) $ as inputs and temperature T as output, is used to fit the three-dimensional welding temperature field. Effect of number of ANN layers and number of neurons on the fitting errors is investigated. It is found that the errors decrease with the number of hidden layers and neural numbers per layers generally. When the number of hidden layers increases from 1 to 6, the maximum temperature error decreases from 74.74℃ to less than 2℃. The three-dimensional temperature field data is obtained by finite element simulation, and the experimental verification is completed by comparing the simulation peak temperatures with the measured results. As an example, an ANN with 4 hidden layers and 12 neurons in each layer were applied to test the performance of the proposed method in storage of the three-dimensional temperature field data during friction stir welding. It is found that the average error between the temperature data stored in ANN and the original simulation data that stored point-by-point is 0.517℃, and the error on the maximum temperature is 0.193℃, while the occupied disk space is only 0.27% of that is required in the conventional point-by-point storage.
  • Tushar Telmasre , Abdelrahman Abdelmotagaly, 高雁飞, 于真真
    中国焊接. 2022, 31(3): 8-16. https://doi.org/10.12073/j.cw.20220616001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    When subjected to the lap shear testing, spot welds created by brazing, resistance welding, or other techniques may fail either by a plug failure mode (also called pull-out mode) or an interfacial shear failure mode. In the past, plug failure mode was thought to be dependent on base metal ultimate tensile strength, spot diameter and plate thickness, while interfacial failure can be determined by interface shear strength and spot area. No fracture mechanics model or failure process is invoked in such an approach, and its predictive capability is often doubted compared to realistic experiments. This work conducts a parametric study to assess the failure behavior as a function of dominant three-dimensional geometric parameters based on the Gurson-Tvergaard-Needleman (GTN) damage mechanics model and no-damage model respectively. Different necking conditions are considered as precursors to the two failure modes in the no-damage model. It is found out that a small ratio of spot diameter to plate thickness promotes interfacial shear failure while a large ratio favors plug failure. Other geometric parameters such as the filler interlayer thickness, if used, play a secondary role. The calculated peak force $ {F_{wt}} $ is not much different between the GTN and no-damage analyses, and better agreement is shown in the small nugget region. Normalized peak force calculated from the GTN model with the porosity $ {f_0} $ set to 0.01 showed the best agreement with pervious tensile shear tests on spot-welded DP980 lap joints in comparison to that calculated from the GTN model with $ {f_0} $ at 0.02 and the no-damage model. Note that heterogeneous distribution of material strength across the joint region was considered in the GTN model, which was estimated based on the hardness map measured across the joint cross section.
  • 黄宏浩, 胡明华, 徐爱杰, 宋育林, 陈华斌
    中国焊接. 2022, 31(3): 17-23. https://doi.org/10.12073/j.cw.20220628001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    The deformation and residual stress generated by the welding process can seriously affect the use of components. As a result, it is very important to understand the evolution of stress and strain during the welding process. The strain measurement method based on digital image correlation (DIC) is an excellent method to detect welding strain and residual stress. The out-of-plane translation and out-of-plane rotation introduce errors to the two-dimensional DIC. In this paper, the causes of errors are analyzed theoretically, and the formulas of errors caused by the out-of-plane displacement and the out-of-plane rotation are derived. The out-of-plane translation experiment and the out-of-plane rotation experiment were carried out to verify the theory , and the experimental results are consistent with the theoretical analysis results. The error caused by the out-of-plane translation can be reduced by increasing the object distance; the error caused by the out-of-plane rotation is greatly affected by the rotation angle.
  • 发永哲, 张宝鑫, 亚伟, Rook Remco , Mahadevan Gautham , Tulini Isotta , 于兴华
    中国焊接. 2022, 31(3): 24-29. https://doi.org/10.12073/j.cw.20220517001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    In order to solve the problem of automatic defect detection and process control in the welding and arc additive process, the paper monitors the current, voltage, audio, and other data during the welding process and extracts the minimum value, standard deviation, deviation from the voltage and current data. It extracts spectral features such as root mean square, spectral centroid, and zero-crossing rate from audio data, fuses the features extracted from multiple sensor signals, and establishes multiple machine learning supervised and unsupervised models. They are used to detect abnormalities in the welding process. The experimental results show that the established multiple machine learning models have high accuracy, among which the supervised learning model, the balanced accuracy of Ada boost is 0.957, and the unsupervised learning model Isolation Forest has a balanced accuracy of 0.909.
  • 肖珺, 雷一鼎, 陈树君, 芦伟, 何恩光
    中国焊接. 2022, 31(3): 30-34. https://doi.org/10.12073/j.cw.20220629001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    T-joint titanium alloy structures are commonly used in aircraft manufacturing, and their laser welding process is relatively mature, but due to the strict requirements of the airplane production, the angular deformation caused by uneven heat input across the sheet is still not negligible, so active control needs to be imposed. In this paper, an active deformation control method based on programmable multi-point flexible support is proposed and validated. In response to the problem that the traditional rigid clamping and pre-stressing are not adapted to the T-structure thin sheet, this study has designed a multi-point flexible support with microcontroller and electric actuators, which can monitor the stress state of the current support position in real time during the welding process and make dynamic adjustment,so that the weld deformation could be effectively reduced in this way.
  • 洪海涛, 韩永全, 陆寅, 王璐, 王一凡
    中国焊接. 2022, 31(3): 35-41. https://doi.org/10.12073/j.cw.20220617001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    Variable polarity plasma arc-gas metal arc welding (VPPA-GMAW) integrates the advantages of VPPA and GMAW, and it is particularly applied to weld thick-plates aluminum alloys. High-speed camera and data acquisition system were used to analyze the arc shape and the welding process electrical signal. According to the analysis of arc swing amplitude and the approximate entropy of arc voltage signal denoised by wavelet threshold method, the influence of VPPA frequency on the arc stability was studied. The results show that the approximate entropy of GMAW arc voltage decreases with the increase of VPPA frequency in a certain range, and the stability of the hybrid arc is significantly improved. The spectral analysis shows that the arc stability is reduced due to the resonance effect between the VPPA and the GMAW arc when the VPPA frequency closes to the GMAW arc pulse frequency. The results are helpful to understand hybrid welding mechanism and the selection of welding process parameters.
  • 赵勇桃, 胡雨晴, 董俊慧, 周军伟
    中国焊接. 2022, 31(3): 42-47. https://doi.org/10.12073/j.cw.20220522001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    By method of TIG, two kinds of welding materials were filled in and under certain welding craft conditions, 1Cr18Ni9Ti and 2Cr13 were welded. The microstructure of two kinds of welded joints were observed and analyzed by OM, SEM. Through seawater immersion test, polarization curves and AC impedance spectroscopy of two kinds of welding joints were obtained. The results show that 2Cr13 and 1Cr18Ni9Ti welded joints are typical columnar crystal, the microstructure is lath martensite + austenite + carbide. The welded joints that filled in 308 and H1Cr21Ni10Mn7Mo welding wires, corrosion resistance has same change rule: Austenite base metal>HAZ near Austenite>welded joint>HAZ near Martensite>Martensite base metal. The every zone contrast of two kinds of welded joint corrosion resistance obtains: the welded joints filled in 308> the welded joints filled in H1Cr21Ni10Mn7Mo.
  • 胡广旭, 杨兴亚, 于兴滨, 魏艳红
    中国焊接. 2022, 31(3): 48-52. https://doi.org/10.12073/j.cw.20211221001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    Since programing complex and dynamic heat source model for welding simulation is a complex job, the parametric methods are studied in this paper. Firstly, an overall flow to achieve automatically modeling welding was introduced. Secondly, an expert module rule for selecting welding heat source model was founded, which is based on simulation knowledge and experiences. Thirdly, a modularity routine method was investigated using writing with C++ programing, which automatically creates subroutines of 3D dynamic heat source model for user. To realize the dynamic weld path, the local weld path coordinate system was moved in the global coordinate system and it is used to model the direction of weld gun, welding path and welding pose. The weld path data file was prepared by the automatic tool for the welding heat source subroutines. All above functions were integrated in the user interface and the connection with architecture was introduced. At last, a laser beam welding heat source modeling was automatically modeled and the weld pool geometry was compared with the reported literature. It demonstrated that the automated tool is valid for welding simulation. Since modeling became convenient for welding simulation using the tool proposed, it could be easy and useful for welding engineers to acquire the needed information.
  • 崔冰, 宋拢雨, 刘正未, 孙盼攀
    中国焊接. 2022, 31(3): 53-60. https://doi.org/10.12073/j.cw.20220620001
    摘要 ( ) PDF全文 ( )   可视化   收藏
    Cu-Sn-Ti brazing filler is a new type of copper-based brazing filler for brazing diamond tools currently used in industry, but it suffers from poor wear resistance, high brazing temperature and low bond strength. This paper provides a way to improve the strength of diamond-brazed joints by adding zirconium carbide and tungsten carbide reinforcing phase particles to the Cu-Sn-Ti alloy, respectively. Diamond particles were attached to Q460 steel using Cu-Sn-Ti composite filler with the addition of the reinforcing phase, and experimental instruments such as scanning electron microscope, X-ray diffractometer and energy spectrometer were used to investigate the brazed joint performance of the composite brazing material for brazing diamond. The results show that the addition of enhanced phase particles resulted in a metallurgical reaction at the joint of the composite brazed diamond, achieving a higher strength joint with no obvious cracks at the interface, while the addition of 15 wt.% WC resulted in excellent wear resistance and the highest hardness at the joint interface.