Influence Analysis of Wedging Tip Fillet for Forming in the Process of Cross Wedge Rolling 4Cr9Si2 Valve

Abstract

Forming process of 4Cr9Si2 martensite refractory steel by cross wedge rolling is simulated by means of rigid-plastic DEFORM-3D software. The influence regularities of cross wedge rolling technical parameter—wedging tip fillet for surface spiral, internal defeats, size reduction on center of symmetry are obtained:It is obvious that surface spiral will be reduced with increasing of the wedging tip fillet due to surface radial force decrease; The duration time of transverse stress and shear stress will be increased, meanwhile the direction of max stress will be changed and metal flow direction will toward transverse direction with increasing of the wedging tip fillet, and consequently these factors lead to higher possibility of internal defeats; Size reduction on center of symmetry will be improved due to the value of axial force Fz decrease with increase of wedging tip fillet. Rolling experiments are carried out to verify the reliability of the simulation results, and qualified part is obtained by means of increasing stretching angle.