A mechanical system for tensile testing of supported films at the nanoscale

Abstract

Standard tensile tests of materials are usually performed on freestanding specimens. However, such requirement is difficult to implement when the materials of interest are of nanoscopic dimensions due to problems related to their handling and manipulation. In the present paper, a new device is presented for tensile testing of thin nanomaterials, which allows tests to be carried out on specimens initially deposited onto a macroscopic pre-notched substrate. On loading, however, no substrate effects are introduced, allowing the films to be freely stretched. The results obtained from a variety of thin metal or polymeric films are very promising for the further development of this technique as a standard method for nanomaterial mechanical testing.

Load Sensor Instability and Optimization of MEMS-based Tensile Testing Devices

“…As a matter of fact, it is rare to find in the literature experimental stress-strain curves of nanoscale materials showing a steep softening branch. One example can be found in Pantano et al (2018), where the stress-strain curve of a poly(methyl methacrylate) (PMMA) film with about 100 nm thickness shows a final softening region with negative slope of ∼-736 N/m. This value approaches (yet is still below) the limit of the load sensor stability region, whose upper bound corresponds to the load sensor stiffness (831 N/m in this case).…”

Gas-Flow-Assisted Wrinkle-Free Transfer of a Centimeter-Scale Ultrathin Alumina Membrane onto Arbitrary Substrates

“…The ultimate tensile strength was measured using a modified method. 46 A 30 nm thick layer of titanium was deposited onto a curved glass by PVD to increase the conductivity for SEM characterization. The surface roughness of the substrates was measured by an atomic force microscope (Dimension 3100, Veeco).…”

“…The air speed was measured by an InFlux flow meter. The ultimate tensile strength was measured using a modified method . A 30 nm thick layer of titanium was deposited onto a curved glass by PVD to increase the conductivity for SEM characterization.…”

Investigation of charges-driven interactions between graphene and different SiO2 surfaces

“…displays [15]. In many cases a strong interaction with the substrate is required, at least at specific locations, as to securely clamp the edge of a freestanding nanoscale resonator [16] or the boundary of a membrane for mechanical tests [17], [18], [19], [20], [21] or to induce strain through a flexible substrate in order to investigate strain engineering properties [22]; whereas in many others the interaction should be as low as possible, as in electro-mechanical switches, or of medium intensity, in order to have well-adhered but sliding graphene flakes able to fold in nanoribbons [23].…”