Objectives This study sought to compare enamel cracks after orthodontic bracket debonding in the surfaces prepared with erbium, chromium: yttrium-scandium-galliumgarnet (Er,Cr:YSGG) laser and the conventional acid-etching technique. Materials and Methods This in-vitro experimental study was conducted on 60 sound human premolars extracted for orthodontic purposes. The teeth were randomly divid...

Full recovery of interfacial bond strength after complete fiber/matrix debonding is achieved with a microencapsulated solvent-based healing chemistry. The surface of a glass fiber is functionalized with microcapsules containing varying concentrations of reactive epoxy resin and ethyl phenylacetate (EPA) solvent. Microbond specimens consisting of a single fiber and a microdroplet of epoxy are te...

The effects of grain-boundary chemistry on the mechanical properties of a high-purity silicon nitride ceramics were investigated, with specific emphasis on the role of oxygen. Variations in the grain-boundary oxygen content, through control of oxidizing heat treatments and sintering additives, was found to result in a transition in fracture mechanism from transgranular to intergranular fracture...

This paper presents an experimental and numerical study of unidirectional carbon fiber composites with a silicone matrix, loaded transversally to the fibers. The experiments show nonlinear behavior with significant strain softening under cyclic loading. The numerical study uses a plane-strain finite element continuum model of the composite material in which the fiber distribution is based on ex...

Damage constitutive models based on micromechanical formulation and a combination of micromechanical and macromechanical effects were developed by the authors to predict progressive damage in aligned and randomly oriented carbon fiber polymer composites. The models are extended in order to account for the microcrack effect on the mechanical behavior of the composites. Progressive interfacial fi...

Wang Liang, Bai Rui-xiang*, Yan Cheng State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology, Dalian 116024, P.R. China * Corresponding author: [email protected] Abstract: This paper studies interfacial debonding behavior of composite beams bonded with piezoelectric material. The focus is put on crack initiation and growth of the piezoelectric adhes...

Introduction: Aseptic loosening of the femoral component continues to be a major long-term complication across a wide range of designs in total hip arthroplasty (THA). Early debonding at the stem/cement interface is emerging as an alarming problem [1] with the roughened surface finishes currently popular in clinical practice. The onset of stem/cement interface radiolucency is commonly regarded ...

This paper presents an extrinsic Fabry-Perot interferometer-based optical fiber sensor (EFPI) for measuring three-dimensional (3D) displacements, including interfacial sliding and debonding during delamination. The idea employs three spatially arranged EFPIs as the sensing elements. In our sensor, the three EFPIs are formed by three endfaces of three optical fibers and their corresponding incli...

In a novel design of lithium-ion batteries, hollow electrode particles coated with stiff shells are used to mitigate mechanical and chemical degradation. In particular, silicon anodes of such coreeshell nanostructures have been cycled thousands of times with little capacity fading. To reduce weight and to facilitate lithium diffusion, the shell should be thin. However, to avert fracture and deb...

Background and objectives: The aim of the study was to evaluate the shear bond strength of brackets bonded with three bonding systems under laboratory conditions and to compare resin tag penetration after debonding. Materials and methods: The study was done on 60 extracted human premolar teeth, divided into three groups of 20 teeth each. Each group was bonded with three different types of bondi...