Pressurized Blister Test Research Articles

Experimental and theoretical characterization of the interfacial adhesion of 2D heterogeneous materials: A review

Two-dimensional (2D) materials have been developed intensively over the last decade, and combining different 2D materials to form heterogeneous 2D materials is anticipated to be more attractive with broader applications. The precise evaluation and prediction of interfacial properties of 2D heterostructures are critical for designing more robust heterostructures and developing advanced, engineered molecular devices. Here, we present a brief review on experimental (namely, atomic force microscopy (AFM), in situ peel test, double cantilever beam, pressurized blister test and sheet-on-bead method) and theoretical techniques (namely, molecular dynamics and density functional theory) for probing the adhesion/interaction energy of the interface of 2D heterogeneous materials and paving the way for future applications.

Alternative methods for fracture energy acquisition in the qualification of composite repair system

Composite repair systems for metallic pipelines presenting a through-wall defect must be qualified in accordance with either ISO 24817 or ASME PCC-2 standards. This qualification method requires a number of hydrostatic tests to obtain the failure pressure. In the oil and gas industry, the failure pressure estimation is often performed using a linear fracture mechanics analysis described in both ISO and ASME standards. These standards require the determination of a constant fracture energy, also called the energy release rate. In the case of monotonically increasing loading histories, in the framework of linear fracture mechanics, brutal interfacial debonding occurs when the fracture energy reaches a critical value. This study is an attempt to show that a simpler test, such as, shaft-loaded and pressurized blister test can be employed as an alternative to hydrostatic tests in the qualification of repair systems. The goal is to obtain experimentally the critical fracture energy using blister tests. Results show a reasonable similarity between the critical energy values found using both pressurized and shaft-loaded blister test with the ones obtained with the standard required hydrostatic tests.

A Refined Theory for Characterizing Adhesion of Elastic Coatings on Rigid Substrates Based on Pressurized Blister Test Methods: Closed-Form Solution and Energy Release Rate.

Adhesion between coatings and substrates is an important parameter determining the integrity and reliability of film/substrate systems. In this paper, a new and more refined theory for characterizing adhesion between elastic coatings and rigid substrates is developed based on a previously proposed pressurized blister method. A compressed air driven by liquid potential energy is applied to the suspended circular coating film through a circular hole in the substrate, forcing the suspended film to bulge, and then to debond slowly from the edge of the hole as the air pressure intensifies, and finally to form a blister with a certain circular delamination area. The problem from the initially flat coating to the stable blistering film under a prescribed pressure is simplified as a problem of axisymmetric deformation of peripherally fixed and transversely uniformly loaded circular membranes. The adhesion strength depends on the delamination area and is quantified in terms of the energy released on per unit delamination area, the so-called energy release rate. In the present work, the problem of axisymmetric deformation is reformulated with out-of-plane and in-plane equilibrium equations and geometric equations, simultaneously improved, and a new closed-form solution is presented, resulting in the new and more refined adhesion characterization theory.

Mechanical Properties of 2D Materials Studied by In Situ Microscopy Techniques

AbstractTwo‐dimensional (2D) materials have been demonstrated as promising building blocks in future electronic and their mechanical properties are quite important for various applications. Due to their atomic thickness and planar nature, the investigation of the mechanical properties and related atomic mechanism are quite challenging. This review focuses on the recently developed in situ techniques based on scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM) in characterization of the mechanical properties of 2D materials. In situ methods used for studying their elastic properties, fracture behavior, and surface/interface energy are introduced in detail. Specifically, the AFM indentation test and microelectromechanical systems (MEMS) device are generally used to investigate the elastic properties; the manipulator based methods show their flexibility in studying the fracture, adhesion, cleavage, and friction properties; atomic level fracture mechanism can be revealed with in situ high resolution TEM (HRTEM); the pressurized blister test and the buckle/wrinkle based methods are widely used to measure the surface/interface properties. Moreover, the influence of sample preparation process, defects and layer numbers to their mechanical properties are also discussed. Finally, the extensions of above methods to investigate the strain‐modulated physical properties of 2D materials are introduced.

Structural deformation of nanomembranes in pressurized blister test

In order to study gas selective membrane, the applied mechanical strain is one of intuitive ways to engineer the properties of nanomembranes. During the gas passing through the membrane, this creates pressure difference across the membrane resulting in the membrane bulged. Basically, pressurized blister can be used to control strain of nanomembranes. This problem is similar to the deformation of the membrane described by Hencky’s solution. The structural deformations of nanomembranes in pressurized blister test in graphene and porous graphene are investigated. This solution provides the membrane profile and the relationship between the pressure and the blister height that can directly estimate strain in the membrane and adhesion energy of the membrane with the substrate for physical measurement.

Theoretical study of adhesion energy measurement for film/substrate interface using pressurized blister test: Energy release rate

In this paper, a new loading method able to subtly control the crack driving force for pressurized blister test was proposed. A theoretical study of the adhesion energy measurement for film/substrate interface using this loading method was presented. Problems considered include solving the exact volume under a circular blister and the elastic strain energy stored in a thin blistering film, determining the work done by the poured colored liquid as external force to the system and the elastic strain energy stored in the compressed air. A new formula of energy release rate was finally presented. A comparison between the work presented here and the existing work was made.

Selective molecular sieving through porous graphene

Membranes act as selective barriers and play an important role in processes such as cellular compartmentalization and industrial-scale chemical and gas purification. The ideal membrane should be as thin as possible to maximize flux, mechanically robust to prevent fracture, and have well-defined pore sizes to increase selectivity. Graphene is an excellent starting point for developing size-selective membranes because of its atomic thickness, high mechanical strength, relative inertness and impermeability to all standard gases. However, pores that can exclude larger molecules but allow smaller molecules to pass through would have to be introduced into the material. Here, we show that ultraviolet-induced oxidative etching can create pores in micrometre-sized graphene membranes, and the resulting membranes can be used as molecular sieves. A pressurized blister test and mechanical resonance are used to measure the transport of a range of gases (H(2), CO(2), Ar, N(2), CH(4) and SF(6)) through the pores. The experimentally measured leak rate, separation factors and Raman spectrum agree well with models based on effusion through a small number of ångstrom-sized pores.

Ultrathin Oxide Films by Atomic Layer Deposition on Graphene

In this paper, a method is presented to create and characterize mechanically robust, free-standing, ultrathin, oxide films with controlled, nanometer-scale thickness using atomic layer deposition (ALD) on graphene. Aluminum oxide films were deposited onto suspended graphene membranes using ALD. Subsequent etching of the graphene left pure aluminum oxide films only a few atoms in thickness. A pressurized blister test was used to determine that these ultrathin films have a Young's modulus of 154 ± 13 GPa. This Young's modulus is comparable to much thicker alumina ALD films. This behavior indicates that these ultrathin two-dimensional films have excellent mechanical integrity. The films are also impermeable to standard gases suggesting they are pinhole-free. These continuous ultrathin films are expected to enable new applications in fields such as thin film coatings, membranes, and flexible electronics.

Ultrastrong adhesion of graphene membranes

As mechanical structures enter the nanoscale regime, the influence of van der Waals forces increases. Graphene is attractive for nanomechanical systems because its Young's modulus and strength are both intrinsically high, but the mechanical behaviour of graphene is also strongly influenced by the van der Waals force. For example, this force clamps graphene samples to substrates, and also holds together the individual graphene sheets in multilayer samples. Here we use a pressurized blister test to directly measure the adhesion energy of graphene sheets with a silicon oxide substrate. We find an adhesion energy of 0.45±0.02 J m(-2) for monolayer graphene and 0.31±0.03 J m(-2) for samples containing two to five graphene sheets. These values are larger than the adhesion energies measured in typical micromechanical structures and are comparable to solid-liquid adhesion energies. We attribute this to the extreme flexibility of graphene, which allows it to conform to the topography of even the smoothest substrates, thus making its interaction with the substrate more liquid-like than solid-like.

Development of a Pressurized Blister Test for Interface Characterization of Aggregate Highly Polymerized Bituminous Materials

Bituminous crack sealants are commonly used for pavement maintenance. While cracks in pavement are inevitable, sealing the cracks helps maintain the integrity of the pavement by preventing water and debris from entering the structure. Sealing cracks increases pavement service life up to 5 years, and this can lead to significant cost savings for the U.S. highway system. Crack sealing is a cost-effective maintenance approach, provided that the right sealant is selected and properly installed. However, sealant selection is difficult because of the lack of a rheology-based standard test that correlates with field performance. To address this drawback, performance-based guidelines for the selection of hot-poured crack sealants have been developed by a research team, including the writers. To complement these guidelines, this paper describes a recently developed adhesion test procedure that predicts interface bonding based on a fundamental property of the interface, interfacial fracture energy (IFE). This recently developed pressurized blister test is a fracture test. The principle of the test is to break the interface bonding by pressurizing the interface between the adhesive and adherend. The amount of pressure and the deformation of the adhesive before and during the debonding period are used to calculate the IFE. The test variation is acceptable because its average coefficient of variation is 8.7%. This paper describes the test apparatus and procedure and discusses the adhesion of several hot-poured bituminous sealants to aluminum, limestone, quartzite, and granite.

Characterization of the interface adhesion of elastic–plastic thin film/rigid substrate systems using a pressurized blister test numerical model

The quality of interface adhesion of an elastic–plastic thin film/rigid substrate system can be characterized by its interface adhesion energy. To estimate the interface adhesion energy, a numerical model for the pressurized blister test has been proposed, which includes three steps: dimensional, forward and reverse analyses. The dimensional analysis is applied to derive a preliminary nondimensional relationship of the interface adhesion energy, and then the forward and reverse analyses are carried out to establish its explicit form and to extract the interface adhesion energy, respectively. The results are in good agreement with experimental measurements, which confirms the effectiveness of the model.

Surgical Adhesive/Soft Tissue Adhesion Measured by Pressurized Blister Test

AbstractThe practical adhesion of equine pericardium membranes bonded with surgical glue has been measured by the bulge-and-blister technique under injection of pressurized distilled water. The value of the interfacial crack propagation energy can be estimated from the critical debonding pressure. The measured practical adhesion energies are weak with regards to those of engineering structural adhesives, but they are reliable enough to allow a comparison between different surgical glues and a study of the influence of the bonding experimental conditions.

A pressurized blister test model for the interface adhesion of dissimilar elastic–plastic materials

A concept of the interface adhesion energy, Γ 0, has been proposed to characterize the quality of interface adhesion of the elastic–plastic materials system. A geometrically nonlinear finite element analysis of a blister test of an elastic–plastic film bonded to an elastic–plastic substrate has been conducted. The fracture process ahead of the crack tip at the interface between the thin film and the substrate is represented in terms of a built-in cohesive model, for which interface adhesion energy and the peak stress required for separation are basic parameters. Effects on the critical pressure of various influencing parameters are studied. The plastic work in the substrate contributes significantly to the critical pressure. Agreement between modeling prediction and measurement evidences the validity of the proposed concept and the method of extracting the interface adhesion energy.

Height-Regulating Scanning Kelvin Probe for Simultaneous Measurement of Surface Topology and Electrode Potentials at Buried Polymer/Metal Interfaces

A height-regulated scanning Kelvin probe (HR-SKP) that is capable of measuring the sample/needle distance and the interfacial electrode potential at the same time was constructed for the study of rough or curved surfaces in humid environments. Moreover, the height regulation led to an improvement of the spatial resolution because the distance between the vibrating needle (i.e., the reference electrode) and the substrate surface was kept to a minimum. The height regulation was performed by a double modulation of the external voltage at different frequencies. The mechanical part of the height regulation is comprised of a piezoelectric translator and a stepping motor in combination, so that both a fine adjustment of the height and a large height range of several millimeters was possible. The z-resolution of the system was about 200 nm, while the lateral spatial resolution was about 15 μm. The HR-SKP was applied to different forms of corrosion including filiform corrosion on organically coated aluminum samples. Moreover, a combination of a pressurized blister test and the HR-SKP was applied for the study of adhesives under both corrosive and mechanical stress. © 2005 The Electrochemical Society. All rights reserved.

A parametric study of a pressurized blister test for an elastic–plastic film-rigid substrate system

Abstract A finite element simulation of a blister test of an elastic–plastic film, bonded to a substrate and subject to plane strain conditions, is performed. A traction-separation law models the fracture process ahead of the crack tip at the interface between the thin film and the substrate. Only two parameters are significant in describing the traction-separation law: adhesion energy, Γ 0 and interface strength, σ ˆ . The dependences of the pressure, P , and the product of the pressure with the central deflection, PH , on the adhesion properties ( Γ 0 and σ ˆ ), the geometry and material properties of the film are studied. The latter quantity ( PH ) has the same unit as the adhesion energy, Γ 0 , and is “conceptually” appropriate for the analysis. We suggest a method to extract the adhesion energy, Γ 0 and the interface strength, σ ˆ , independently from the total energy dissipated.

Derivation of the strain energy release rate G from first principles for the pressurized blister test

The strain energy release rate, G, is derived from first principles and is shown to be consistent with the exact numerical solution by Cotterell and Chen (Int. J. Fract. 86 (1997) 191). Comparison with the classical Rayleigh–Ritz energy method and other published methods shows that the gradual change in blister profile over the entire loading process must be considered for the correct G to be calculated.

The bending to stretching transition of a pressurized blister test

The mechanical behavior of a thin blistering film under a uniform pressure changes from a bending to a stretching membrane as the thickness and flexural rigidity decrease. An analytical solution is found for the elastic response and the strain energy release rate based on an average membrane stress approximation.