J. Phys. IV France
Volume 115, June 2004
Page(s) 243 - 250

J. Phys. IV France
115 (2004) 243
DOI: 10.1051/jp4:2004115029

The effect of aluminium on mechanical properties and deformation mechanisms of hadfield steel single crystals

E.G. Zakharova1, I.V. Kireeva1, Y.I. Chumlyakov1, A.A. Shul'mina1, H. Sehitoglu2 and I. Karaman3

1  Siberian Physical-Technical Institute, 634050 Tomsk, Novosobornaya Sq., 1, Russia
2  University of Illinois, 1206 West Green Street, Urbana, IL 61801, USA
3  Texas A&M University, College Station, TX 77843-3123, USA

On single crystals of Hadfield steel (Fe-13Mn-1.3C, Fe-13Mn-2.7Al-1.3C, wt.%) the systematical investigations of deformation mechanisms - slip and twinning, stages of plastic flow, strain hardening coefficient depending on orientation of tensile axis have been carried out by methods of optical and electron microscopy, x-ray analysis. Is has been shown that the combination of low stacking fault energy ( $\gamma_{\rm {SF}}=0.03$J/m 2) with high concentration of carbon atoms in aluminium-free steel results in development of the mechanical twinning at room temperature in all crystal orientations. The new type of twinning with formation of extrinsic stacking fault has been found out in [001] single crystals. Experimentally it has been established that alloying with aluminium leads to increase of stacking fault energy of Hadfield steel and suppresses twinning in all orientations of crystals at preservation of high values of strain-hardening coefficients $\theta$.

© EDP Sciences 2004