Numerical Simulation Study On Springback Of0Cr21Ni6Mn9N Stainless Steel Tube NC Bending

0Cr21Ni6Mn9N stainless steel with high strength, low magnetic conductivity,good corrosion resistant performance, stable structure under the using temperature; thetube parts made by0Cr21Ni6Mn9N stainless steel can satisfy the requirement of theproducts with lightweight, low consumption, and have a role to absorb the impactingenergy; Therefore,0Cr21Ni6Mn9N stainless steel tube usually used as the gas or liquidtube in aviation, aerospace. Springback is one of the key factors affecting the quality ofbending tube. It is of important practical guiding significance that research on thespringback mechanism, and quantitative analysis the influence of geometric andprocessing parameters on springback. In this paper, the main research contents andresults are as follows:Based on the finite element analysis software ABAQUS, a whole process finiteelement model of0Cr21Ni6Mn9N stainless steel tube was established in NC bending.The distribution of stress and strain and mechanical characteristics of the tube wasanalyzed during bending, retracting and springback process.The influence of geometric and processing parameters on the springback angle andradius of0Cr21Ni6Mn9N stainless steel tube were studied by single factor method. Theresults show as follows: the springback angle increases as the bending angle increaseslinely,the springback radius decreases as the bending angle increases, and satisfies thepower equation；Both the springback angle and radius increase with increasing of therelative bending radius, relative diameter; the order from high to low of the springbackangle and radius for different forms of mandrels are without mandrel, rounded typemandrel, hemisphere type mandrel; With the decreasing of mandrel extension length e,the increasing of bending speedω, the friction coefficient between tube and mandrelμm,bending dieμb, the clearance between tube and mandrel Cm, bending die Cb, thespringback angle and radius increase gradually. The influence of push assistant speed ofpressure die Vp; friction coefficient, clearance between tube and pressure dieμp, Cp; thefriction coefficient between bending tube and wiper die μcon springback angle andradius are not obvious.Five more significant processing parameters were selected as the independentvariables according to the influence of various processing parameters on springbackangle and radius，such as mandrel extension length e，the friction coefficient between tube and mandrelμm, bending dieμb; the clearance between tube and mandrel Cm,bending die Cb. The springback angle and springback radius prediction models wereestablished by linear regression method; then comparison the calculation results ofspringback prediction model with the simulation test results. Finally, the step ofspringback compensation was introduced in detail with specific instance for bent tube.