journal article

Journal Article

Text

Applied Physics Letters. 2014, 105(2), p. 021902

Multiple-shocks induced nanocrystallization in iron

American Institute of Physics

English

Text

2014-07-14

https://doi.org/10.1063/1.4890389

Matsuda T., Sano T., Arakawa K., et al., Applied Physics Letters, 105(2), 021902 (2014) https://doi.org/10.1063/1.4890389

We found that multiple shots of femtosecond laser-driven shock pulses changed coarse crystalline iron grains with a size of 140 μm into nanocrystals with a high density of dislocations, which had never been observed in conventional shock processes. We performed metallurgical microstructure observations using transmission electron microscopy (TEM) and hardness measurements using nanoindentation on cross-sections of shocked iron. TEM images showed that grains with sizes from 10 nm through 1 μm exist within 2 μm of the surface, where the dislocation density reached 2 × 10 15m-2. Results of the hardness measurements showed a significant increase in hardness in the nanocrystallized region. We suggest that the formation of a high density of dislocations, which is produced by a single shock, induces local three-dimensional pile-up by the multiple-shocks, which causes grain refinement at the nanoscale. © 2014 AIP Publishing LLC.

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Matsuda T., Sano T., Arakawa K., et al. Multiple-shocks induced nanocrystallization in iron. Applied Physics Letters, 105(2), 021902 and may be found at https://doi.org/10.1063/1.4890389.

89438

Multiple-shocks induced nanocrystallization in iron

American Institute of Physics

English

2014-07-14

Applied Physics Letters

105

2

021902

https://doi.org/10.1063/1.4890389

https://hdl.handle.net/11094/89438