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A pressure contact connector design was evaluated based on contact load and tested under temperature cycling. The damage induced on gold contact surfaces in a pressure contact connector was examined using visual inspection methods. The connector was subjected to mating and unmating operations, as well as repeated thermal excursions to determine environmental factors which would accelerate damage. Pressure indentations and wear tracks were found on the contact bumps and fingers resulting from the temperature cycling. This wear of the contact finish could make the connector susceptible to corrosion by exposing the base metal after repeated thermal cycling. Wear was assumed to be induced due to insufficient contact pressure between the electrical contacts. An alternative design was examined using finite element analysis which appears to provide a high contact load which should result in a lower contact resistance and less wear.

Multichip modules using lamination techniques to make the substrate (MCM‐Ls) are a natural extension of printed circuit technology to meet the ever increasing demands of system integration and density. As with other forms of MCM, the interconnection density is so high that many circuits need only two signal layers. The substrate can also incorporate layers to control thermal expansion and extract heat. MCM‐L substrates are extraordinarily versatile; they can accommodate packaged ICs (e.g., fine pitch SMT), unpackaged ICs, other MCMs and odd‐form components. There is a large and growing number of MCM‐L suppliers offering solutions for a wide range of sizes, complexities, performance and market sectors at competitive prices.

Analyses were performed during the conceptual design stage of a 20in. threaded connector for deep water J‐pipe lay, as part of a research project developed by Tecnomare and partly funded by the EEC. The joint consists of two parts, namely a pin and a box, provided with cylindrical threads. It was essential for the joint design to be fully leak‐proof for both internal and external pressure and this requirement had to be satisfied also under the maximum bending moment allowable for the sealine. Sealing was accomplished on a cone surface by screwing the pin into the box until yield was reached. The FEM analysis was carried out primarily to check that the pin and box remain pressed to one another over the sealing surface in every design condition with adequate pressure to prevent leakage. For this purpose, the analysis was a powerful design technique, as it gave an easy understanding of the structural behaviour and provided proper stiffness by making the joint either larger or thinner wherever required. The main characteristic of this work is that FEM analysis has been utilized as a design method rather than as a check. The analysis was performed by means of ADINA (Automatic Dynamic Incremental Non‐linear Analysis) program. Contact pressure between sealing surfaces, as achieved during the joint screwing phase, was modelled through thermal elongation. Pressure loads and external forces were superimposed through a step‐by‐step procedure, by accounting for the elastoplastic behaviour all around the sealing surface. In order to verify the behaviour of the mechanical joint, six prototypes have been fabricated and tested under the design loads of the lay phase and the operative life. The results of the tests confirmed the correct design and the results of non‐linear finite element analysis. The most important performances of the joint can be summarized as follows: (1) the make‐up phase is rapid and easy: no problems of frictional pick‐up took place; (2) no leakage happened during the internal pressure tests: the pressure of 300atm (1.5 times the design internal pressure) was maintained for 12h; (3) the load conditions of the second series of tests were: 200atm of internal pressure and the maximum allowable bending moment relevant to the pipe: after 2h no leakage happened. This paper describes the model used for the analysis, discusses its implications and the most important results achieved in comparison with the tests of the experimental phase.

A contact featured flexible circuit connector was designed to meet the high speed signal performance needs of the VAX 9000 Multi Chip Unit. With contact densities of 200 I/O over approximately 2 square inches, this connector has the highest contact density of any high performance signal connector in any DEC system. This paper discusses the use of a specially designed tester to characterise and measure connector performance against its design goals.

The purpose of this paper is to propose a computational approach in order to help establish the effect of various self-piercing rivet (SPR) process and material parameters on the quality and the mechanical performance of the resulting SPR joints.

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the SPR process; (b) determination of the mechanical properties of the resulting SPR joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the SPR joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified SPR connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all SPR joints is associated with a prohibitive computational cost.

It is found that the approach developed in the present work can be used, within an engineering optimization procedure, to adjust the SPR process and material parameters (design variables) in order to obtain a desired combination of the SPR-joint mechanical properties (objective function).

To the authors’ knowledge, the present work is the first public-domain report of the comprehensive modeling and simulations including: self-piercing process; virtual mechanical testing of the SPR joints; and derivation of the constitutive relations for the SPR connector elements.

The reliability of an electronic connector is more important now than at any time in the past. Not only has system complexity grown but operating environmental conditions are more severe and system speed has made circuits less tolerant of any interference. With “fly by wire” aircraft, and fully computer controlled communications systems, even more demanding performance is required. However system reliability is calculated, whether by MIL‐HDBK‐217B, or latest S.A.E. data, or the more traditional MTBF calculations, it is clear that connections form a key part of the total statistics. As a greater number of components have become interconnected, either by rack, module, panel, backplane, or PCB, pin counts on connectors have slowly increased. A connector which only a few years ago would have 160 ways now has 220 or 330 ways. Finally, as component sizes shrink and on‐chip integration grows there is very significant pressure to reduce the size of connectors whilst at the same time further improving reliability.

This paper aims to reproduce the electrical connector intermittent fault behaviours with step-up vibration stress while maintaining the integrity of the product.

A dynamic model of an electrical connector under vibration is established for contact resistance analysis. Next, the dynamic characteristics of contact resistance are analysed, and cumulative damage theory is used to calculate the damage under different stresses during the intermittent fault reproduction test. To reduce damage and improve efficiency, the step-up stress is used for the reproduction test.

The proposed method can reproduce the intermittent fault behaviour, and the step-up stress test is more efficient than the constant stress test.

Step-up stress is used for intermittent fault reproduction, and the quantitative relationships between intermittent fault and product damage can be further studied.

It is expected that the proposed methodology can help engineers to reproduce the intermittent fault behaviours to facilitate the detection and diagnosis of intermittent fault and to improve equipment safety.

The mechanism of electrical connector reproduction is analysed and the step-up stress test is used for intermittent fault reproduction.

Pin-loaded hubs with fitted bush are used in industrial connector-type elements. They are subjected to varying radial forces leading to variable stress distribution. The literature provides various pressure distribution expressions adapted essentially for symmetric geometries and fixed load condition (circular hubs, half-infinite geometries, axial load, tangential load, etc.). This study aims to take into account the geometrical conditions of industrial connector-type elements and presents a model for pressure distribution based only on geometric parameters, maximal pressure and contact angle value for the case of fit pin-loaded hub.

The finite element computation for the contact problem shows that the pressure distribution of the pin-loaded hub under various inclined forces (from 0° to 180°) is a parabolic distribution. This distribution can be defined by three parameters which are θ_A, θ_B and P_max. The study assumes that the distribution is symmetric and that P_max can be modeled using force F, hub radius R, hub thickness b and the half contact angle are θ_A.

The new proposal pressure distribution parameters are easy to identify. Even for the non-symmetric pressure distribution, the study denotes that the errors on evaluating θ_A and θ_B keep the analytical model still in good agreement with finite element computations.

Only the neat fit case was studied.

Pin-loaded joints are connector-type elements used in mechanical assemblies to connect any structural components and linkage mechanisms such as connecting rod ends of automotive or shear joints for aircraft structure.

The good correlation between finite element computations and model results shows the validity of the assumptions adopted here. Analytical fatigue models, based on this stress distribution, could be derived in view of a fatigue lifetime calculation on connecting hub. Friction, pin deformation and local plastic effects under pin-loading are the main phenomena to take into account to further enrich this model.

The purpose of this paper is to propose a computational approach to establish the effect of various flow drilling screw (FS) process and material parameters on the quality and the mechanical performance of the resulting FS joints.

Toward that end, a sequence of three distinct computational analyses is developed. These analyses include: (a) finite-element modeling and simulations of the FS process; (b) determination of the mechanical properties of the resulting FS joints through the use of three-dimensional, continuum finite-element-based numerical simulations of various mechanical tests performed on the FS joints; and (c) determination, parameterization and validation of the constitutive relations for the simplified FS connectors, using the results obtained in (b) and the available experimental results. The availability of such connectors is mandatory in large-scale computational analyses of whole-vehicle crash or even in simulations of vehicle component manufacturing, e.g. car-body electro-coat paint-baking process. In such simulations, explicit three-dimensional representation of all FS joints is associated with a prohibitive computational cost.

Virtual testing of the shell components fastened using the joint connectors validated the ability of these line elements to realistically account for the strength, ductility and toughness of the three-dimensional FS joints.

The approach developed in the present work can be used, within an engineering-optimization procedure, to adjust the FS process and material parameters (design variables) in order to obtain a desired combination of the FS-joint mechanical properties (objective function).