The Aluminum Alloy Corbel Of CRH-7EMU Optimized Structure And Casting Technology

With the rapid development of high speed railway，the light weight trains become aninevitable trend of improving train speed, while aluminum alloy has advantages of lowdensity, high specific strength and modulus, which has wide application prospects on theEMU train. However, the research on complex structure aluminum alloy corbel is still atthe initial stage at the moment.This paper studies the aluminum alloy corbel of CRH-7EMU mainly from threeaspects: Firstly, considering welded corbel structure of steel plate to design the castingaluminum alloy corbel structure, and taking finite element analysis on the static strengthand fatigue strength of designed structure, if the result is reasonable, this design can meetthe force requirement, if not, it need to be redesigned.Secondly, based on CAD/CAEtechnology, we can research casting technology of aluminum alloy corbel.This paperdesigns two kinds of casting technology, sand gravity casting process and sand lowpressure casting process, by using numerical simulation technology to analyse filling andsolidification process in order to predict defects to make sure reasonable casting systemscheme and optimized casting process parameters. Finally, Through actual tracking thesample of aluminium alloy corbel producing process, analyse and put forward solutionsof casting defects(porosity, shrinkage cavity, shrinkage porosity, cold shut, slag inclusion,crack etc.) for further optimization of process scheme.Through the metallographic structure and mechanical properties analysis, whichshows that the casting with compact structure can achieve: σ_b≥275MPa, δ≥2.0, HB≥80.The nondestructive testing and pressure test of mold cavity show that casting has noobvious internal flaw; air tightness of casting is qualified, which meets the press castingdemand.