Weld bead morphology plays an important role in welding procedure specification and welding process planning.In order to obtain the quantitative relationship between process parameters and weld morphology of DH36 mari...Weld bead morphology plays an important role in welding procedure specification and welding process planning.In order to obtain the quantitative relationship between process parameters and weld morphology of DH36 marine steel plate,grey correlation method was used to study multiple morphology characteristics simultaneously.Eighteen experimental runs were proposed according to orthogonal method.With grey correlation theory,three response objectives,aspect ratio,depth of penetration and weld were transformed into a single grey correlation grade(GRG).The process parameters were quantitatively correlated to the GRG value and optimized with the target of maximum aspect ratio,minimum depth of penetration and maximum weld area.The results show that the optimized weld bead morphology is better than other weld bead morphology.The relative error of the predicted GRG with respect to the actual value is 5.06%,which further verifies the accuracy of the established model.The microstructure and hardness analysis suggests that the optimized welded joint has obtained required mechanical properties.The research outcomes provide a theoretical basis for multi-objective optimization of arc welding morphology in practical applications.展开更多
In order to establish the groove model for intersecting structures of circular tubes,mathematical model of the intersecting line is established by the method of analytic geometry,and parametric equations are thus dete...In order to establish the groove model for intersecting structures of circular tubes,mathematical model of the intersecting line is established by the method of analytic geometry,and parametric equations are thus determined.The dihedral angle,groove angle and actual cutting angle for any position of the intersecting line are derived as well.In order to identify groove vectors for two pipes,a new analytical method,i.e.coplanarity of vectors,is further proposed to complete the groove model.The established model is virtually verified by programming and simulation calculation in the MATLAB environment.The results show that groove vectors of intersecting structures simulated by MATLAB are consistent with the theoretical groove model,indicating that the theoretical groove model established in this paper is accurate,and further proves that the proposed coplanarity of vectors for solving groove vectors is correct and feasible.Finally,a graphical user interface(GUI)is developed by MATLAB software to independently realize functions such as model drawing,variable calculation and data output.The research outcome provides a theoretical foundation for the actual welding of circular intersecting structures,and lays an essential basis for weld bead layout and path planning.展开更多
基金Natural Science Foundation of Fujian Province(Grant No.2020J01873)Technology Major Project of Fujian Province(Grant No.2020H03018).
文摘Weld bead morphology plays an important role in welding procedure specification and welding process planning.In order to obtain the quantitative relationship between process parameters and weld morphology of DH36 marine steel plate,grey correlation method was used to study multiple morphology characteristics simultaneously.Eighteen experimental runs were proposed according to orthogonal method.With grey correlation theory,three response objectives,aspect ratio,depth of penetration and weld were transformed into a single grey correlation grade(GRG).The process parameters were quantitatively correlated to the GRG value and optimized with the target of maximum aspect ratio,minimum depth of penetration and maximum weld area.The results show that the optimized weld bead morphology is better than other weld bead morphology.The relative error of the predicted GRG with respect to the actual value is 5.06%,which further verifies the accuracy of the established model.The microstructure and hardness analysis suggests that the optimized welded joint has obtained required mechanical properties.The research outcomes provide a theoretical basis for multi-objective optimization of arc welding morphology in practical applications.
基金This work was supported by Natural Science Foundation of Fujian Province(Grant No.2020J01873)Science and Technology Major Project of Fujian Province(Grant No.2020HZ03018).
文摘In order to establish the groove model for intersecting structures of circular tubes,mathematical model of the intersecting line is established by the method of analytic geometry,and parametric equations are thus determined.The dihedral angle,groove angle and actual cutting angle for any position of the intersecting line are derived as well.In order to identify groove vectors for two pipes,a new analytical method,i.e.coplanarity of vectors,is further proposed to complete the groove model.The established model is virtually verified by programming and simulation calculation in the MATLAB environment.The results show that groove vectors of intersecting structures simulated by MATLAB are consistent with the theoretical groove model,indicating that the theoretical groove model established in this paper is accurate,and further proves that the proposed coplanarity of vectors for solving groove vectors is correct and feasible.Finally,a graphical user interface(GUI)is developed by MATLAB software to independently realize functions such as model drawing,variable calculation and data output.The research outcome provides a theoretical foundation for the actual welding of circular intersecting structures,and lays an essential basis for weld bead layout and path planning.