Significant increase in hardness value in an Fe-Mn-Si based shape memory alloy after high pressure torsion processing

This work was focused on the effect of high-pressure torsion (HPT) processing on the microstructure and mechanical properties of an Fe-۱۵Mn- ۵Si- ۷Cr- ۵Ni (wt.%) shape memory alloy. Based on the X-ray diffraction pattern, the initial microstructure of the alloy in the solution annealed (SA) condition was a miXture of the austenite and martensite. However, after applying HPT for ۳ turns, there was an increase in the martensite amount and a decrease in the amount of austenite. Also, HPT processing resulted in grain refinement and a significant increase in microhardness of this alloy to ~۶۱۰Hv, which was about ۲.۵ times higher than the SA condition.

کلیدواژه ها:

Fe based shape memory alloys ، High pressure torsion ، Mechanical properties ، Severe plasticdeformation