Size effect and strain rate sensitivity in benzocyclobutene film

Abstract

The mechanical properties of benzocyclobutene film are investigated at the nanoscale by nano-indentation using atomic force microscopy (AFM). The force versus indentation depth data were collected with two different AFM tips of radii ϳ20 and ϳ380 nm. A strong size effect of the plastic flow stress was observed as the radius of the indenter tip was reduced. More important, the material exhibited pronounced strain rate sensitivity when probed at the nanoscale, while it was rate insensitive at larger scales. These two size effects were quantified by analytic and finite element modeling.

Self-similarity and finite-size effects in nano-indentation of highly cross-linked polymers

“…The glass transition temperature of the cross-linked polymer is T g ∼ 165 • C as determined by means of differential mechanical analysis on thin film test samples with a broad transition region extending over ±10 • C above and below T g . 1 The indentation experiments reported here were performed with an atomic force microscope (AFM) cantilever comprising a capacitive platform for exerting a loading force by electrostatic means and a resistive heater for controlling the tip temperature [13,14]. The indenter tip has a conical shape, with an aperture angle of 65 • and an apex radius of ∼15 nm as shown in the electron micrograph in figure 1(a).…”

“…The desire to determine thermal and mechanical material properties of thin films by nano-indentation has grown substantially in the past decade [1][2][3][4]. This demand stems from the increased technological importance of thin films in general and of polymer films in particular, with a clear emphasis on lithographical applications such as nano-imprint techniques [5][6][7] and data storage [8].…”

Mechanical properties of porous methyl silsesquioxane and nanoclustering silica films using atomic force microscope

“…The samples were indented with maximum applied loads in the range of 5-60 lN. A very slow loading rate dZ=dt ¼ 10 nm=s was employed to avoid the signature of material strain rate sensitivity (if any) in the data [16]. Each indent was made in a single load-unload sequence.…”

“…In addition to the conventional nanoindenters, the use of atomic force microscope (AFM) for nanoindentation has experienced an increasing popularity [10][11][12][13][14][15][16]. In AFM nanoindentation, the usual imaging tip is replaced by a very sharp diamond tip which is used for both indentation and the subsequent imaging of the residual impressions.…”

Novel Molecular Precursor of Lanthanide Complexes with LongChain Mono Cis-Butene Dicarboxylate to the Controlled Synthesis of Y2O3:Eu3+ Phosphors

“…At local scale, material properties such as, hardness and elastic modulus often differ from those acquired by conventional measurements. [1][2][3][4] Still, precise knowledge of those parameters is frequently required both to reliably assess the material properties and to design new applications. Nanonindentation testing, also known as depth sensing indentation (DSI), 5 is a popular technique to address similar issues.…”