X-ray Diffraction Studies of Forward and Reverse Plastic Flow in Nanoscale Layers during Thermal Cycling

Journal Article · Tue Jan 01 00:00:00 EST 2013 · Materials Research Letters

DOI:https://doi.org/10.1080/21663831.2013.843602· OSTI ID:1095644

Gram, Michael D ^[1]; Carpenter, John S ^[2]; Payzant, E Andrew ^[3]; Misra, Amit ^[2]; Anderson, Peter M ^[1]

---

1. Ohio State University, Columbus
2. Los Alamos National Laboratory (LANL)
3. ORNL

The biaxial stress-strain response of layers within Cu/Ni nanolaminates is determined from in-plane x-ray diffraction spectra during heating/cooling. Thinner (11 nm) Cu and Ni layers with coherent, cube-on-cube interfaces reach ~1.8 GPa (Cu) and ~2.9 GPa (Ni) without yielding. Thicker (21 nm) layers with semi-coherent interfaces exhibit unusual plastic phenomena, including extraordinary plastic work hardening rates, and forward vs. reverse plastic flow with small (~10%) changes in stress, and evidence that threshold plastic stress in Ni layers is altered by preceding plastic flow in Cu layers. Line energy, pinning strength, net interfacial dislocation density and hardness are provided.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1095644
• Journal Information: Materials Research Letters, Vol. 1, Issue 4; ISSN 2166--3831
• Country of Publication: United States
• Language: English