Simulation And Experiment Research On Process Of Superplastic Forming Of Industrial 5083 Aluminum Alloy

With the rapid development of rail transit industry in the world,the technology of rail vehicle manufacturing has entered a new stage of development.Safety,lightweight,fire resistance and environmental protection have become important symbols for measuring modern trains.The use of aluminum alloy materials with low density,environmental protection,fire resistance is an important way to achieve the lightweight of rail trains.However,at room temperature,aluminum alloy material has poor plasticity and poor forming performance.Superplastic forming technology is one of the effective methods for aluminum alloy forming instead of cold stamping.It is of great significance to solve the bottleneck problem of light weight forming of trains.The poor performance and the low efficiency are two problems in industrial Aluminum superplastic forming areas.This paper take the train door pillar cover parts as the research object,aim to study industrial Aluminum alloy parts superplastic forming process.The main research work in this paper as follows:1.The effects of different temperature and strain rate conditions on the high temperature rheological stress and elongation of industrial 5083 aluminum alloy were analyzed by thermal tensile test of constant strain rate.The strain rate-strain rate sensitivity coefficient curve of 5083 aluminum alloy at 0.40 was established,and the optimum process parameters of superplastic forming were obtained.2.In this paper,a two-step forming method combining preformed and superplastic forming is proposed for the complex three-dimensional surface parts of the train door pillar cover parts,which not only ensures the shape precision,size precision and product quality of the forming parts meet the performance requirements,but also shortens the production time and saves the production cost.3.Established the finite element numerical simulation model of the train door pillar cover parts,cofficient of friction and strain rate in the process of parts forming was analyzed,and the forming efficiency under different strain rate were obtained,and got the corrected time-pressure curve,as the train door pillar cover provide theoretical instructions for industrial production.4.In this paper,the mould structure and process of the train door pillar cover parts was designed,and the test study of superplastic forming of the train door pillar cover parts was carried out using the SHP72-1000 superplastic forming special hydraulic press.The thickness distribution of the test parts is compared with the finite element simulation results.The reliability of Finite element analysis simulation is proved.At the same time,the part of the train door pillar cover after forming was comprehensively tested to meet the design requirements.