Limits...
Wrinkle motifs in thin films.

Budrikis Z, Sellerio AL, Bertalan Z, Zapperi S - Sci Rep (2015)

Bottom Line: Although these patterns are part of everyday experience and are important in industry, they are not completely understood.Here, we report simulation studies of a previously-overlooked phenomenon in which pairs of wrinkles form avoiding pairs, focusing on the case of graphene over patterned substrates.Our simulations uncover the generic behaviour of avoiding wrinkle pairs that should be valid at all scales.

View Article: PubMed Central - PubMed

Affiliation: ISI Foundation, Via Alassio 11/c, 10126 Torino, Italy.

ABSTRACT
On length scales from nanometres to metres, partial adhesion of thin films with substrates generates a fascinating variety of patterns, such as 'telephone cord' buckles, wrinkles, and labyrinth domains. Although these patterns are part of everyday experience and are important in industry, they are not completely understood. Here, we report simulation studies of a previously-overlooked phenomenon in which pairs of wrinkles form avoiding pairs, focusing on the case of graphene over patterned substrates. By nucleating and growing wrinkles in a controlled way, we characterize how their morphology is determined by stress fields in the sheet and friction with the substrate. Our simulations uncover the generic behaviour of avoiding wrinkle pairs that should be valid at all scales.

No MeSH data available.


Related in: MedlinePlus

Wrinkle interaction tests on multilayers illustrate how avoiding pairs evolve with sheet thickness.Shown here are height maps for (a) 2-, (b) 5-, and (c) 10-layer graphene sheets. Panels (d–f) show the corresponding trace of the stress tensor outside the wrinkles. To make the shapes of wrinkles clearer, their interiors (defined by a height threshold of 2 Å) are left white. The nucleus separations are X = Y = 160 nm. All images have the same scale; the scale bar in panel (c) represents 100 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4355740&req=5

f6: Wrinkle interaction tests on multilayers illustrate how avoiding pairs evolve with sheet thickness.Shown here are height maps for (a) 2-, (b) 5-, and (c) 10-layer graphene sheets. Panels (d–f) show the corresponding trace of the stress tensor outside the wrinkles. To make the shapes of wrinkles clearer, their interiors (defined by a height threshold of 2 Å) are left white. The nucleus separations are X = Y = 160 nm. All images have the same scale; the scale bar in panel (c) represents 100 nm.

Mentions: Importantly, our linearized simulations exhibit avoiding pairs of wrinkles, an example of which is highlighted in Fig. 1(d,e). The pairs are stable and their appearance is robust against changes of simulation details such as substrate interactions. In addition, like Yamamoto et al., we find increasing the thickness of the graphene sheet hinders its conformation to the substrate (compare our Fig. 1 with Fig. 6 of Ref. 17). This is especially apparent in regions where close-spaced particles are positioned on the vertices of a polygon, as in the region indicated in Fig. 1(a,b). As highlighted in Fig. 1(f,g), the sheet in this region “pops up” when its thickness (and hence ratio of bending to stretching costs) increases. In the rest of this paper, we study these two characteristic behaviours in greater detail.


Wrinkle motifs in thin films.

Budrikis Z, Sellerio AL, Bertalan Z, Zapperi S - Sci Rep (2015)

Wrinkle interaction tests on multilayers illustrate how avoiding pairs evolve with sheet thickness.Shown here are height maps for (a) 2-, (b) 5-, and (c) 10-layer graphene sheets. Panels (d–f) show the corresponding trace of the stress tensor outside the wrinkles. To make the shapes of wrinkles clearer, their interiors (defined by a height threshold of 2 Å) are left white. The nucleus separations are X = Y = 160 nm. All images have the same scale; the scale bar in panel (c) represents 100 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4355740&req=5

f6: Wrinkle interaction tests on multilayers illustrate how avoiding pairs evolve with sheet thickness.Shown here are height maps for (a) 2-, (b) 5-, and (c) 10-layer graphene sheets. Panels (d–f) show the corresponding trace of the stress tensor outside the wrinkles. To make the shapes of wrinkles clearer, their interiors (defined by a height threshold of 2 Å) are left white. The nucleus separations are X = Y = 160 nm. All images have the same scale; the scale bar in panel (c) represents 100 nm.
Mentions: Importantly, our linearized simulations exhibit avoiding pairs of wrinkles, an example of which is highlighted in Fig. 1(d,e). The pairs are stable and their appearance is robust against changes of simulation details such as substrate interactions. In addition, like Yamamoto et al., we find increasing the thickness of the graphene sheet hinders its conformation to the substrate (compare our Fig. 1 with Fig. 6 of Ref. 17). This is especially apparent in regions where close-spaced particles are positioned on the vertices of a polygon, as in the region indicated in Fig. 1(a,b). As highlighted in Fig. 1(f,g), the sheet in this region “pops up” when its thickness (and hence ratio of bending to stretching costs) increases. In the rest of this paper, we study these two characteristic behaviours in greater detail.

Bottom Line: Although these patterns are part of everyday experience and are important in industry, they are not completely understood.Here, we report simulation studies of a previously-overlooked phenomenon in which pairs of wrinkles form avoiding pairs, focusing on the case of graphene over patterned substrates.Our simulations uncover the generic behaviour of avoiding wrinkle pairs that should be valid at all scales.

View Article: PubMed Central - PubMed

Affiliation: ISI Foundation, Via Alassio 11/c, 10126 Torino, Italy.

ABSTRACT
On length scales from nanometres to metres, partial adhesion of thin films with substrates generates a fascinating variety of patterns, such as 'telephone cord' buckles, wrinkles, and labyrinth domains. Although these patterns are part of everyday experience and are important in industry, they are not completely understood. Here, we report simulation studies of a previously-overlooked phenomenon in which pairs of wrinkles form avoiding pairs, focusing on the case of graphene over patterned substrates. By nucleating and growing wrinkles in a controlled way, we characterize how their morphology is determined by stress fields in the sheet and friction with the substrate. Our simulations uncover the generic behaviour of avoiding wrinkle pairs that should be valid at all scales.

No MeSH data available.


Related in: MedlinePlus