Difference between carbon and nitrogen in thermal stability of metastable 18%Cr-8%Ni austenite

作者：Masumura Takuro^*; Tsuchiyama Toshihiro; Takaki Setsuo; Koyano Tamotsu; Adachi Kazuhiko

来源：Scripta Materialia, 2018, 154: 8-11.

DOI：10.1016/j.scriptamat.2018.05.019

• Austenitic steels
• Stainless steels
• Martensitic phase transformation
• Thermodynamics
• Thermal stability

The effects of carbon and nitrogen addition on the athermal alpha'-martensitic transformation in metastable 18%Cr-8%Ni austenite are investigated. The thermal stability of austenite in nitrogen-added steel is higher than that in carbon-added steel, and the difference between the effects of carbon and nitrogen addition becomes remarkable as the amount of both elements increases. As the two-step transformation (gamma -> epsilon -> alpha') always occurs in metastable 18%Cr-8%Ni austenite, the suppression of epsilon-martensite results in the thermal stabilization of austenite. Nitrogen is more effective than carbon for increasing the stacking fault energy, leading to a higher thermal stability of the nitrogen-bearing 18%Cr-8%Ni steels.

• 出版日期2018-9