Application Of ABAQUS Secondary Development In Constitutive Modeling Of Titanium Alloy And Cutting FEA

Ti-6Al-4V alloy has become popular material in aviation,aerospace,chemical and mechanical industries owing to its excellent physical performances and mechanical properties,such as high specific strength,good resistance of corrosion and oxidation.However,the difficult machinability of the Ti-6Al-4V alloy restricts its application and development.Therefore,the exploration on the mechanism of the machining of Ti-6Al-4V alloy has become a hot research.As the thermal stress coupling deformation of high strain,high strain rate and high temperature commonly happens in the machining process of Ti-6Al-4V alloy,it is important to choose the suitable constitutive model to describe the deformation behavior of titanium alloy.Based on this,finite element simulation,which plays an important role in guiding the process of titanium alloy,has positive significance on improving the manufacturing level of aviation industry.In this paper,concerning the applicability of the constitutive models in ABAQUS finite element software materials library,ABAQUS has been secondary developed by means of VUMAT user subroutine interface.JC model,JCM model and KHL model were embedded in the main program.The writing of the VUMAT subroutine requires the use of FORTRAN programming language.After developing the VUMAT subroutine,different FEA models of 7075 alloy and the Ti-6Al-4V alloy materials have been established.The simulation results of using the JC constitutive model which was developed by VUMAT subroutine were compared with the results of using the JC constitutive model which was already contained in ABAQUS.The correctness of the VUMAT subroutine is verified by the comparisons.Based on the uses of JC model,JCM model and KHL model to define the material properties,the orthogonal cutting process of Ti-6Al-4V alloy was modeled by finite element method.Combined with the FEA model cutting conditions,the Ti-6Al-4V orthogonal cutting experiments were designed,and the results of the simulations which used three different constitutive models were verified.Compared with the chip formation and the cutting force of experimental and simulated results,it shows that the models which used the three constitutive models are all in good agreement with the experimental results.In addition,JCM model and KHL model are more accurate than JC model.It indicates that JCM model and KHL model can better describe the deformation behavior of Ti-6Al-4V alloy in the cutting process.Meanwhile,the programme of VUMAT subroutine in this paper is proper,and the method of establishing the finite element simulation model can accurately predict the actual processing.