Nanomechanical insights into the deformation behavior of austenitic alloys with different stacking fault energies and austenitic stability

作者：Misra R D K^*; Zhang Z; Jia Z; Surya P K C Venkat; Somani M C; Karjalainen L P

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2011, 528(22-23): 6958-6963.

DOI：10.1016/j.msea.2011.05.068

• Austenitic steel
• Deformation
• Microstructure
• Nanoindentation
• Pop-in

Nanoscale experiments and electron microscopy were combined to probe the deformation behavior in near defect-free volume of three austenitic steels (Type 316L, 301LN, and TWIP steel) with different stacking fault energies and austenite stability. In all the three steels, the occurrence of first pop-in is related to nucleation of dislocations in the small defect-free volume. But the second and subsequent pop-ins describe the load-displacement response resulting from the multiplication, motion and pile-up of dislocations and twinning in stable 316L stainless steel, phase transition such as strain-induced austenite-to-martensite phase transformation in metastable 301LN steel, and twinning in TWIP steel. Pop-ins associated with deformation twinning occur at a lower displacement in 1WIP steel as compared to 316L steel, consistent with the lower stacking fault energy of TWIP steel. Both strain-induced martensite formation and twinning involve variant selection.

• 出版日期2011-8-25