Evolution of Microstructure and Texture of Lead-Patenting Treated Pearlite Steel Wire during Cold Drawing Process

The microstructure and texture evolution of pearlitic steel wires after lead patenting (LP) treatment and after cold drawing for different passes were analyzed by means of transmission electron microscopy (TEM),scanning electron microscopy (SEM) and electron back scattering diffraction (EBSD)systerm .The results indicate that the undistorted and equiaxial grains formed in the pearlite steel wire after LP treatment and uniform sorbite was obtained.The pearlite interlamella spacing and the thickness of cementite lamellae decreased linearly with the decrease of the diameter of the steel wire,in addition,the cementite lamellae exhibited plastic deformation ability to some extent.During the cold-drawing process,the ferritic matrix showed coordination deformation from the center to surface.Although the area fraction of 〈110〉 fiber texture of ferrite parallel to the drawing direction increased gradually with the increase of true strain,its growth rate was inhomogeneous.The strength of 〈110〉 fiber texture increased constinuously and the distribution of uncorrelated misorientation angle-relative frequency curves deviated from Mackenzie distribution with the increase of true strain,meanwhile,there were two peaks appeared at the range of 10°-20°and 45°-60°.