The Effect of Nb on Mechanical Properties of Quenching and Partitioning Steels
In order to study the effect of alloy elements on mechanical properties of quenching and partitioning steels, the Q&P heat treatments on different chemical composition steels were carried on in lab. The tensile test results indicated the strength of Nb+Ti-bearing steel was not increasing as expected, but lower than that of the Nb+Ti-free steel, and the elongation was raised to 26％ from 9％. The Nb+Ti-bearing steel microstructures after tensile test were detected by TEM and found a certain amount of twins in the deformed microstructure while the deformed microstructure mainly was lath martensite in Nb+Ti-free steel, which means the addition of Nb and Ti elements could cause the twinning induced plasticity by inhibiting the phase transformation from austenite to martensite. Based on above analysis, adding trace Nb element could greatly increase the stacking fault energy of the retained austenite, which is beneficial to the formation of twins, and the formation of twins would lower the strength slightly and raise the elongation drastically.
quenching and partitioning twinning induced plasticity niobium stacking fault energy
ZHU Shuai KANG Yong-lin REN Kang-kang WANG Chuan
School of Materials Science and Engineering. University of Science and Technology Beijing, Beijing 100083, China
国际会议
The 6th International Conference on High Strength Low Alloy Steels(第六届高强度低合金钢国际会议HSLA Steels2011)
北京
英文
740-743
2011-05-31（万方平台首次上网日期，不代表论文的发表时间）