Study On The Parameterized Modelling Technology Of The Welding Process For Invar Alloy Mold And Process Optimization

Invar alloy,which is also known as “King of Metal”,has been widely used in the manufacturing composite models for its low thermal expansion coefficient which is similar to that of composite materials.Due to the large size of the molds and the complex distribution of the weld bead,the optimization process of the welding process is complex and the cost is relatively high.The parameterization finite element method can be applied to optimize the welding process,while the traditional analysis process is complex and inefficient.The complex mold can be divided into several typical joints,and the parameterization modeling of typical joints is carried out to realize the parameterization modeling of Invar alloy mold,which improve the efficiency of modeling and welding process optimization significantly.First,a parameterized scheme of the typical Invar alloy mold structure is constructed.the secondary development methods of two special software are investigated to obtain the implementation scheme of parametric modeling for Invar alloy mold structure.This scheme consists of two basic modules: the parametric meshing of typical structure and parametric simulation of the welding process,corresponding to the finite element mesh process and the finite element model pre-processing settings.Then,a parametric modeling method is developed basing on a command stream file,and parametric meshing and pre-processing settings are performed for two typical structures of Invar alloy molds.Considering the meshing requirements of the finite element analysis and the meshing process,the parametric meshing module has been developed,and users can quickly perform finite element meshing entering key parameters.When the size of the component changes,the related parameters can be adjusted to perform the reconstruction of the finite element mesh quickly.The parameter pre-processing settings module,which is conducted by editing and developing a command stream file,can realize automatic loading from material parameters,weld definitions to boundary conditions,working conditions,etc.,and dramatic simplifies repetitive work in the setup of finite element preprocessing,thereby improving the efficiency of finite element analysis.Finally,the practicability and reliability of the parametric modeling method are verified.Based on the two modules,a parametric modeling system is developed.The system is used to model two typical structures of Invar alloy molds,to obtain the optimal process parameters and welding sequence.The welding tests are performed according to the simulation results.Comparative analysis shows that the system satisfies the need of high accuracy and reliability,and enhance the efficiency of finite element modeling.