Microstructures and Properties of Ultrafine Grained Iron by Rolling

摘要

Microstructures and properties of ultrafine grained (UFG) iron by different rolling processing are investigated. By applying the asymmetric rolling (ASR), the equiaxed UFG iron with the grain size of 0.9 urn has been obtained due to the shear strain induced by the mismatch of the two roll during ASR. With the same rolling reduction, the ASR processed iron shows higher yield strength than that of the symmetrically rolled one. When the ASR processed iron is further symmetrically rolled, the grain morphology maintains equiaxed and the grain size decreases to about 0.3 um.