The delamination process in notched composite plates under flexural loading has been investigated using finite element analysis. Cohesive elements implemented in the commercial finite element package ABAQUS have been used in the region around the drilled-hole, and positioned between layers where delamination was observed during experiments presented in an accompanying paper. The delamination in...

Drilling of glass fibre reinforced plastic (GFRP) composite is different from metallic materials due to its mechanical properties. The drilling of this material may generate delamination of drilled holes on workpiece. The purpose of this paper is to investigate the influence of the cutting parameters, such as cutting speed and feed rate, point angle of drill and material thickness on delaminati...

Drilling of carbon fibre/epoxy laminates is usually carried out using standard drills. However, it is necessary to adapt the processes and/or tooling as the risk of delamination, or other damages, is high. These problems can affect mechanical properties of produced parts, therefore, lower reliability. Production of higher quality holes is a challenge to everyone related with composites industry...

Fibre reinforced plastics are increasing their importance as one of the most interesting groups of material on account of their low weight, high strength and stiffness. To obtain good quality holes, it is important to identify the type of material, ply stacking sequence and fibre orientation. In this paper, the drilling of quasi-isotropic hybrid carbon+glass/epoxy plates is analyzed. Two commer...

Due to the miniaturization of integrated circuits, their thermo-mechanical reliability tends to become a truly critical design criterion. Especially the introduction of copper and low-k dielectric materials cause some reliability problems. Numerical simulation tools can assist developers to meet this challenge. This paper considers the first bond integrity during wire bond qualification testing...

The instability of structures due to compression is one the most critical issues related aircraft components. Especially in composite materials, which have poor out-of-plane mechanical properties, buckling load must be assessed ensure that are within safe limits compared operating loads. In presence delamination, becomes catastrophic, as propagation delamination can dramatically reduce stiffnes...

A recent variational mechanics analysis of microcracking damage in cross-ply laminates of the form [(S)/90n]s, where (S) is any orthotropic sublaminate much stiffer than [90n], has been extended to account for the presence of delaminations emanating from the tips of microcracks in the [902n]T sublaminate. The new two-dimensional stress analysis is used to calculate the total strain energy, effe...

Effect of elastic anisotropy on indentation-induced thin film interfacial delamination, especially, at the initiation and early growth stage, is examined. The indentation load is modeled as a constant pressure over an expanding semi-spherical cavity. The delamination process is approached by a cohesive zone model. The rest of the problem is formulated within the general anisotropic elasticity t...

Abstract— Due to the superior physical and mechanical properties Glass fiber-reinforced (GFRP) composite materials are very attractive for applications like aerospace and air craft structural components. This results a large number of research papers on machining of these composite laminates. Out of all the machining operations, most commonly used operation is drilling. However, drilling operat...

Three-dimensional transient deformations of a laminate comprised of several unidirectional fiber reinforced layers perfectly bonded to each other and subjected to a blast load are analyzed by the finite element method with an in-house developed, verified and fully validated code with rate-dependent damage evolution equations for anisotropic bodies. The continuum damage mechanics approach employ...