Stainless steel Fe-21Cr-6Ni-9Mn （SS 21-6-9）, with ~21% Cr, ,~6% Ni, and ~ 9% Mn in weight percentage, has wide applications in extensive fields. In the present study, SS 21-6-9 is compressed up to 250 GPa, and its c...Stainless steel Fe-21Cr-6Ni-9Mn （SS 21-6-9）, with ~21% Cr, ,~6% Ni, and ~ 9% Mn in weight percentage, has wide applications in extensive fields. In the present study, SS 21-6-9 is compressed up to 250 GPa, and its crystal structures and compressive behaviors are investigated simultaneously using the synchrotron angle-dispersive x-ray diffraction technique. The SS 21-6-9 undergoes a structural phase transition from fcc to hcp structure at ~ 12.8 GPa with neglectable volume collapse within the determination error under the quasi-hydrostatic environment. The hcp structure remains stable up to the highest pressure of 250 GPa in the present experiments. The antiferromagnetic-to-nonmagnetic state transition of hcp SS 21-6-9 with the changes of inconspicuous density and structure, is discovered at ~50 GPa, and revealed by the significant change in c/a ratio. The hcp SS-21-6-9 is compressive anisotropic： it is more compressive in the c-axis direction than in the a-axis direction. Both the equations of states （EOSs） of fcc and hcp SS 21-6-9, which are in accordance with those of fcc and hcp pure irons respectively, are also presented. Furthermore, the c/a ratio of hcp SS 21-6-9 at infinite compression, R∞, is consistent with the values of pure iron and Fe-10Ni alloy.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.U1230201,11274281,and 11304294)the Industrial Technology Development Program,China(Grant No.9045140509)the Funds from the Chinese Academy of Sciences(Grant Nos.KJCX2-SW-N03 and KJCX2-SW-N20)
文摘Stainless steel Fe-21Cr-6Ni-9Mn （SS 21-6-9）, with ~21% Cr, ,~6% Ni, and ~ 9% Mn in weight percentage, has wide applications in extensive fields. In the present study, SS 21-6-9 is compressed up to 250 GPa, and its crystal structures and compressive behaviors are investigated simultaneously using the synchrotron angle-dispersive x-ray diffraction technique. The SS 21-6-9 undergoes a structural phase transition from fcc to hcp structure at ~ 12.8 GPa with neglectable volume collapse within the determination error under the quasi-hydrostatic environment. The hcp structure remains stable up to the highest pressure of 250 GPa in the present experiments. The antiferromagnetic-to-nonmagnetic state transition of hcp SS 21-6-9 with the changes of inconspicuous density and structure, is discovered at ~50 GPa, and revealed by the significant change in c/a ratio. The hcp SS-21-6-9 is compressive anisotropic： it is more compressive in the c-axis direction than in the a-axis direction. Both the equations of states （EOSs） of fcc and hcp SS 21-6-9, which are in accordance with those of fcc and hcp pure irons respectively, are also presented. Furthermore, the c/a ratio of hcp SS 21-6-9 at infinite compression, R∞, is consistent with the values of pure iron and Fe-10Ni alloy.
