Research On Bulging Process Of 0Cr17Ni4Cu4Nb Stainless Steel Thin-walled Ring Parts

With the development of modern aviation engine industry,various new materials are emerging constantly,among which the 0Cr17Ni4Cu4 Nb material with high strength,high toughness,corrosion resistance and low price is emerging in people's eyes.0Cr17Ni4Cu4 Nb material is a kind of martensitic precipitation-hardening heat-resistant steel.High strength,corrosion resistance,oxidation resistance and weldability.At the same time,this material at about 600 ? has high heat strong resistance,oxidation resistance and resistance to sulfuric acid,phosphoric acid,hydrochloric acid corrosion and stress resistance.Based on the above advantages,it has been applied to some extent in aero engine.Although this material has the above good performance,but the forming performance of the material is very poor,its elongation at room temperature is equivalent to part of titanium alloy.As a result,its thin-walled forming parts have not been widely used in aircraft engines.In this paper an engine 0Cr17Ni4Cu4 Nb thin-walled circular pieces for the study of the carrier,0Cr17Ni4Cu4 Nb sheet formability study,for the cup drawing test,limit,bore hole test,room temperature deep drawing test,ball bottom taper cup test and high temperature tensile test,evaluation of the bulging of the material performance,flanging formability,deep drawing performance,stamping performance and different temperature tensile properties,in order to determine the specific parts processing scheme to provide effective reference.Three parts processing schemes are proposed,including inner expansion and outer expansion,thermal expansion and step expansion.In this paper,the method of numerical simulation is used to study the effect of different swelling amount on the wall thickness distribution and surface quality of the part,as well as the stress distribution on the surface of the part of the part with different expansion.Developing specific parts forming experiments to validate the feasibility of bulging bulging step by step and step,and analyses the influence of bulging velocity,bulging parts thickness thinning and the influence of the inner surface scratch,studied the size is unqualified,the causes of defects such as scratches and control scheme of solving processes of the parts is easy to crack and form surface rounded place don't die,transfer problem of rounded corners is greater than the technical requirements,processing of qualified parts.