skip to main content

SciTech ConnectSciTech Connect

Title: Effect of temperature on the nano/microstructure and mechanical behavior of nanotwinned Ag films

In situ and ex situ annealed nanotwinned (NT) Ag thin films have been investigated by TEM and tensile testing to reveal the thermal stability of the twin boundaries, grain boundaries, dislocation densities, and their respective influence of the macroscopic yield stress. The NT Ag films synthesized by magnetron sputtering form both coherent (CTB, Σ3{111}) and incoherent (ITB, Σ3{112}) twin boundaries that are thermally stable up to 473 K (200 Celsius), i.e., no obvious changes in grain size, twin spacing, and yield stress. In situ TEM observations show the dislocations become mobile at 453 K (180 Celsius) resulting in dislocation annihilation primarily at twin and grain boundaries. Rotation of grains with low-angle grain boundaries was observed during in situ heating, resulting in the growth of columnar grains above 453 K (180 Celsius). However, no noticeable changes in the spacings of CTBs were observed during the entire in situ and ex situ annealing [up to 873 K (600 Celsius)]. The increase in grain size and concomitant decrease in yield stress following annealing at various temperatures can be described by the Hall-Petch relationship, demonstrating that grain size rather than twin spacing is most sensitive to thermal annealing and plays a dominant role inmore » the deformation of NT Ag films.« less
 [1] ;  [1] ;  [1] ;  [1] ;  [1]
  1. Ames Lab., Ames, IA (United States)
Publication Date:
OSTI Identifier:
Report Number(s):
Journal ID: ISSN 1073-5623; PII: 3028
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science
Additional Journal Information:
Journal Volume: 46; Journal Issue: 9; Journal ID: ISSN 1073-5623
ASM International
Research Org:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org:
Country of Publication:
United States
36 MATERIALS SCIENCE columnar growth; thermostability; twin spacing; dislocation density; yield stress