Rearch On Cold Extrusion Forming And Hardening Law Of MJ Groove Profile Self-locking Nut Of A286Superalloy

A286superalloy self-locking nuts are mainly used for aero-engine fasteners,which have some advantages as follow, good self-locking ability, long life, high heatresistance, large axial load and so on. This paper studied the technique of coldextruding forming of A286superalloy self-locking nut of solid-solution state A286superalloy, and the finite element numerical simulation analysis was done. First of all,the solid-solution state A286superalloy was compressed in Gleeble-1500D thermalsimulation testing machine at room temperature, the strain rate is0.1,1,10s-1,respectively. Building the flow stress model of A286and resulting data into theDEFORM simulation software, extensive material database. Then according to resultof the process analysis of the part model the mold structure and workpiece bySolidworks3D software. With the help of numerical simulation software DEFORMrigid-plastic element simulation was done for cold extrusion forming. The maximumprincipal stress distribution, parameters of the velocity and travel-load was analyzedduring forward extrusion hollow pieces and forward extrusion solid piece. Based onthe analysis result, forward extrusion hollow pieces was selected for experiment.Subsequent processing the semi-finished products got from experiment, the hardnesstesting, metallographic analysis, scanning electron microscopy (SEM) and axial loaddetection were done. According to the results of performance testing, compoundextrusion was designed and modeled the mold structure and workpiece by Solidworks3D software. Composite extrusion was simulated by DEFORM simulation software,through the analysis of the stress distribution, strain distribution, the maximumprincipal stress distribution, velocity field and travel-load parameters. Optimize moldstructure, improve the flow of metal, and according to the simulation results design ofthe mold assembly drawing. This paper designed technology and mould according to knowledge andexperience, and then employ numerical analysis and redesign. Shorten the design cycleof process and die, reduced the cost. This paper adopted composite extrusion moldingto take shape the nut, with large deformation, high utilization of materials and goodextrusion performance.