Recent trends in reliability and fatigue life analysis of electronic devices have involved developing structural integrity models for predicting the operating lifetime under vibratory and thermal environmental exposure. Solder joint reliability is the most critical issue for the structural integrity of surface mounted electronics. Extensive research has been done on thermal behavior of solder j...

Among the various techniques available, ultrasonic Lamb waves offer a convenient method of evaluating composite materials. Since the Lamb wave velocity depends on the elastic properties of a structure, an effective tool exists to monitor damage in composites by measuring the velocity of these waves. Lamb wave measurements can propagate over long distances and are sensitive to the desired in-pla...

On the Norwegian coastline, sea temperatures are low throughout the year, and the personnel operating Sea King rescue helicopters are required to wear survival suits during over-sea flights. Paradoxically, this may lead to a situation where the pilots are subject to heat stress during flight (1). Thermal stress may result in fatigue and impaired pilot performance, which may raise the risk of pi...

In this paper we present the main features of the ITER Divertor final dlesign from an engineering point of view and describe the present choices regarding layout, geometry and material selection. The assessment of the detailed design shows that the divertor is able to withstand the thermal and electromagnetic loading conditions foreseen for ITER, and that the estimated lifetime of the Plasma Fa...

The gas turbine exhaust uptakes in the HALIFAX class frigates of the Canadian Navy have experienced thermally-induced fatigue cracking since soon after the commissioning of these ships. The uptake structure is heavily stiffened in order to meet shock resistance requirements. Unfortunately, the result has been that thermal expansion of the uptake shell is constrained, thus every flash-up and shu...

An efficient reliability assessment approach is used to estimate the reliability of a return expansion joint. This component is part of a large power generation system. In order to perform the reliability assessment task, Computational Fluid Dynamics (CFD), Finite Element Method (FEM), Fatigue analysis, and Monte Carlo Simulation (MCS) tools are integrated. The process starts with CFD simulatio...

In recent years, ultrasonic methods have been developed that can measure the mechanical stiffness of composites. The Lamb wave velocity is directly related to the material parameters, so an effective method exists to ascertain the stiffness of composites by measuring the velocity of these waves. In this study, a Lamb wave measurement system was used to measure the bending and out-of-plane stiff...

The thermo mechanical reliability of copper plated through holes (PTH) in printed circuit boards is normally determined by different tests e.g. thermo cycle test (TCT), interconnect stress test (IST) or highly accelerated thermal shock (HATS). During these tests the plated copper is exposed to stresses and strains which are below the tensile strength and the fracture strain, respectively, which...

During the long-term operation, mallets of the forging hammers are exposed to thermal fatigue due to the cyclic temperature changes and impact loads. Taking into account very high price, and a risk of buying frequently the new parts, the necessity of their reparation becomes obvious. The forging hammer mallet (Figure 1), is primarily exposed to the impact compressive loads, and partially also t...