Experimental And Simulation Research On Aluminum Alloy Dynamic Mechanical Properties Of Train Body

The 6-series aluminum alloy is a medium strength alloy with good technological and mechanical properties.Due to its excellent crush resistance,corrosion resistance and good weldability,it has been successfully used in train bodies of high-speed railways.Among many 6 series aluminum alloys,the most widely used and the most typical are the 6005A-T6 and 6082A-T6.Rail vehicles are faced with the risk of accidental collision accidents during their service.Due to its particularity,train collision cannot be verified by experimental means,while simulation analysis can effectively simulate specific conditions.The stress-strain curve of materials under high strain rate can further establish a reliable constitutive model.Accurate constitutive model is the key to numerical simulation.At present,there are few studies on the stress-strain relationship between 6005A-T6 and 6082A-T6 aluminum alloys at high strain rates.Based on the above background,this article focuses on three levels of research:1.Carried out quasi-static mechanical experiments and dynamic mechanical experiments on 6005A-T6 and 6082A-T6 aluminum alloys for train bodies,focusing on the dynamic mechanical properties of 6005A-T6 and 6082A-T6 aluminum alloys.Split Hopkinson pressure bar(SHPB)experimental device was used to study the dynamic compression performance of two aluminum alloys with different strain rates under impact load.The results show that the strain rate has a certain effect on the dynamic yield stress of 6005A-T6 and 6082A-T6 aluminum alloys.As the strain rate increases,the dynamic yield stress gradually increases,but it is not obvious.The dynamic yield stress is higher than that of the 6005A-T6 aluminum alloy.2.Based on the results of quasi-static and dynamic mechanical tests,the corresponding stress-strain curves and dynamic yield stress were obtained,and the Johnson-Cook model was used to fit and build 6005A-T6 and 6082A-T6 aluminum alloys for train bodies.Constitutive model.The results show that the JC constitutive model basically coincides with the experimental data.3.Based on the above test results,the finite element model of the SHPB experimental device was established,and the SHPB dynamic compression test was simulated using the finite element method through ANSYS / LS-DYNA software and compared with the test data,and the comparison waveforms were basically consistent.At the same time,the influence of the two factors of friction coefficient and eccentricity between the rods on the experiment was studied.