Channeling cracks in low-k dielectrics have been observed to be a key reliability issue for advanced interconnects. The constraint effect of surrounding materials including stacked buffer layers has been studied. This paper analyzes the effect of interfacial delamination on the fracture condition of brittle thin films on elastic substrates. It is found that stable delamination along with the gr...

Drilling is the most frequently employed operation of secondary machining for fiber-reinforced materials owing to the need for structure joining. Delamination is one of the serious concerns during drilling. Practical experience shows that an eccentric twist drill or an eccentric candle stick drill can degrade the quality of the fiber reinforced material. Comprehensive delamination models for th...

in this work, homogeneous thermochemical co-precipitation method was used to fabricate w-25wt%cu nanocomposite. synthesized nanocomposite powder was calcined and reduced. a hydrogen atmosphere sintering at 1200oc for 105 consolidated the product up to a density close to 98% theoretical density. wear experiment were carried out using a pin-ondisc set up at three normal loads of 5, 10 and 15 n an...

Finite element analysis of the delamination crack propagation in laminated composites is presented. Fracture mechanics based Virtual Crack Closure Technique (VCCT), and the cohesive element technique, have been used to simulate the delamination initiation and propagation under Mode-I type loading. Detailed description of the parameter selection process for these two techniques with ABAQUS®/Stan...

The inconsistencies accompanied with material properties tipically cause the rise of delamination risk in composites made of different types of glass and crabon fibers. In this study, the delamination of a composite beam reinforced with a carbon layer under bending load is investigated. To this end, a small piece of a wind turbine blade root in the form of a heterogeneous laminated plate is sim...

Delamination is a critical form of failure in composite laminates which is partitioned into a combination of three pure modes namely; opening, shearing and tearing (modes I, II and III respectively). Each fracture mode contributes to the total energy required for delamination growth, due to a combination of the different damage mechanisms that occur under each mode 1-2 . To formulate reliable m...

Drilling carbon/epoxy laminates is a common operation in manufacturing and assembly. However, it is necessary to adapt the drilling operations to the drilling tools correctly to avoid the high risk of delamination. Delamination can severely affect the mechanical properties of the parts produced. Production of high quality holes with minimal damage is a key challenge. In this paper, delamination...

The FOSDT (the First Order Shear Deformation Theory) is taking into consideration to study the static behavior of a bimorph beam, with a delamination zone between the upper and the lower layer. The effect of limit conditions and lengths of the delamination zone are presented in this paper, with a PVDF piezoelectric material application. A FEM “Finite Element Method” is used to discretize the be...

Results are presented from a numerical investigation of the effect of the shape of the delamination front on energy release rate distribution in a laminated carbon fibre reinforced epoxy end-notched flexure test specimen. The deformation behaviour of the specimen has been computed by threedimensional nonlinear finite element analyses using a recently developed layered 3D-shell element. The dist...

Delamination is considered for thin elastic 'lms that are bonded to cylindrical substrates and subject to an equi-biaxial compressive pre-stress. Results for both positive and negative curvatures are obtained. The 'lm buckles or de2ects (depending on the sign of the curvature) away from the substrate inducing mixed mode stress intensities at the edge of the delamination. The energy release rate...