LI Yang
,
LU Yu-peng
,
WANG Chong
,
LI Shi-tong
,
CHEN Lu-bin
钢铁研究学报(英文版)
The residual austenite and its stability in commercial 60Si2Mn steel treated by quenching and partitioning (Q-P) were investigated. The Q-P heat treatment was carried out using a system of ordinary electric furnace—oil bath box—electric furnace. Cryogenic treatments at different temperatures were performed to assess the thermal stability of residual austenite. The microstructure, particularly residual austenite, was analyzed using optical microscope and X-ray diffraction (XRD), and the microhardness and Rockwell hardness were measured. The residual austenite with the volume fraction as much as 137% and the HRC hardness level of 41 were achieved, and the residual austenite is relatively stable.
关键词:
JIANG Zhou-hua
,
LI Shuang-jiang
,
LI Yang
钢铁研究学报(英文版)
A phase diagram was drawn through thermodynamic calculation to understand the equilibrium conditions of 2MgO·SiO2, MgO·Al2O3, 3Al2O3·2SiO2, and 2MgO·2Al2O3·5SiO2 formation in Mg-Al-Si-O system of 430 stainless steel melts at 1873 K. Further, the thermodynamic formation and transformation conditions of MgO·Al2O3 inclusion were discussed. The following results are obtained when wSi=026% and wO=10×10-5 in molten steel. The uniphase cordierite inclusion is difficult to exist stably; MgO·Al2O3 inclusion cannot be formed in case of wAl being less than 1×10-6; 3Al2O3·2SiO2 would change to MgO·Al2O3 and 2MgO·SiO2 in turn with increasing the Mg content when wAl is above 17×10-6; with the formation of MgO·Al2O3 inclusion, Al content increases with increasing Mg content when wMg is over 17×10-9. For equilibrium condition and calculated steel composition, 2MgO·SiO2 inclusion would be formed ultimately and MgO·Al2O3 is almost inexistent.
关键词:
phase diagram
,
thermodynamic calculation
,
MgO·Al2O3 inclusion
,
430 stainless steel
