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This paper investigates the application of thick film hybrid circuit technology on ceramic substrate in comparison to the main stream substrate FR-4 (Flame Retardant 4) for PCB implementation. The study is based on computer models for these very substrates in order to simulate the propagation of heat through convection and conduction within the material boundaries. In order to simulate electronic components surface mounted, different heat sources are randomly arranged on physical contact to the surface of the material under investigation. The results emphasize and discern the usage of both substrates and its most suitable environment verifying the application towards vehicular integration. Future study may include experimental analysis for simulated data verification and validation of thick film hybrid circuit technology for the automotive industry.

The utilization of Laser welding process has increased during last years in several areas of industry, due to many benefits that can be achieved with this technology, such as: flexibility, productivity and quality. Thus, the optimization of Laser welding processes has been considered as a “green field” to be explored by Laser manufacturers, automation companies and process/project engineers. Nowadays there are few researches that provide a roadmap for Laser welding processes improvement that approaches both the aspects and characteristics applied to evaluate the Laser weld application performance. Therefore, this paper has per its main purpose through an exploratory study to provide parameters toward continuous improvement of Laser welding process considering both types of Lasers: Laser spot weld and Laser seam weld of stainless steel joints, thus this work may be considered as theoretical and practical reference to be applied by people involved with Laser welding applications.

One of the most evident trends in automotive sector is miniaturization. It is related to considerable benefits due to the potential of mass reduction, cost reduction and efficiency improvement. It involves many different automobile components and most of them are facing challenges to achieve the targets defined by car makers and final consumers. Specifically for wiring harness, it seems to be many manufacturing and process challenges to be surpassed in order to fully perceive the benefits expected with miniaturization, internally and externally. So this article aims to present an overview of literature as well as reporting of experts on this issue mentioning some of the challenges that global automotive wiring harness manufacturers are facing. Subjects as assembly automation, terminal connection and small gauge cables are discussed in the article and also a general overview of how those problems are being addressed in order to meet customer requirements.

The fundamental relationship between semi-solid processing and microstructure and their effect on the flow characteristics of semi-solid metals have been studied for several years. However, how the process related microstructure influences fatigue properties has not been given the same attention. This study examines the influence of process-related microstructure on the fatigue properties of semi-solid formed A357 alloys. High-solid-fraction (62% solid) and low-solid-fraction (31% and 36% solid) semi-solid formed A357 was tested in axial fatigue with a stress ratio (R) equal to -1. The high solid fraction (HSF) material had better fatigue properties than the low solid fraction (LSF) material. This is attributed to the fatigue crack initiation mechanisms, as related to the fatigue crack initiation features and the strengths of the materials.

There are an increasing number of applications for resonant micromachines. Accelerometers, angular rate sensors, voltage controlled oscillators, pressure and chemical sensors have been demonstrated using this technology. Several of these devices are employed in vehicles. Vibrating devices have been made from silicon, quartz, GaAs, nickel and aluminum. Resonant microsystems are in constant motion and so present new challenges in the area of reliability for vehicular applications. The impact of temperature extremes, cyclic fatigue, stiction, thermal and mechanical shock on resonant device performance is covered.

This paper presents a simplified thermal model for round catalytic converters in steady state operation. Using this model, the analytic solution for the temperature distribution in the monolithic substrate is obtained. This analytic solution in the substrate is, then, combined with those in the intumescent mat [1] and the metal shell to obtain the temperature profile in the radial direction of the converter except for three unknown temperatures at the three material interfaces, which can be solved using an Excel application program. This analytical temperature solution facilitates the studies of the effects of various design parameters such as the exhaust gas temperature, exhaust gas flow rate, substrate cell geometry, converter dimensions, and ambient temperature and flow, etc.

The increasing features and complexity of today's automotive architectures are becoming increasingly difficult to manage. Each new innovation typically requires additional mechanical actuators and associated electrical controllers. The sheer number of black boxes and wiring are being limited not by features or cost but by the inability to physically assemble them into a vehicle. A new architecture is required which will support the ability to add new features but also enable the Vehicle Assembly Plants to easily assemble and test each subsystem. One such architecture is a distributed multiplex arrangement that reduces the number of wires while enabling flexibility and expandability. Previous versions have had to deal with issues such as noise immunity at high switching currents. The LIN Bus with its low cost and rail-to-rail capability may be the key enabling technology to make the multiplexed architecture a reality.

The lateral runout of disc brake corner components can lead to the generation of brake system pulsation. Emphasis on reducing component flatness and lateral runout tolerances are a typical response to address this phenomenon. This paper presents the results of an analytical study that examined the effect that the attachment of the wheel to the brake corner assembly could have on the lateral distortion of the rotor. An analysis procedure was developed to utilize the finite element method and simulate the mechanics of the assembly process. Calculated rotor distortions were compared to laboratory measurements. A statistical approach was utilized, in conjunction with the finite element method, to study a number of wheel and brake corner parameters and identify the characteristics of a robust design.

Desiring to push thermoplastic poly-olefin (TPO) technology to its fullest limits and to confirm our position as the leader in the manufacturing of environmentally friendly TPO instrument panels, we have designed a process to manufacture 100% recycled instrument panel skins. This closed-loop process begins with extruding 100% recycled TPO flake into sheet stock to be painted and vacuum formed. The painted sheet is vacuum formed and the offal is ground into regrind flake, ready to be extruded again, thus completing the closed-loop process. This paper will describe a 100% closed loop recycling process for TPO instrument panels, discuss the intense validation process for recycled material and prove the robustness and durability of this interior solution.

Although the Six Sigma [1] concept has become very popular in industrial sectors, very little is said about how to start a successful implementation in a Corporation, or when it should be initiated, and the most important, who should be addressed to lead this task. Its methodologies are widely observed by different sectors of the automotive market, typically focusing in projects with a potential financial impact, following the DMAIC sequence. More than just financial return, this sophisticated tool, has a direct impact on Quality in different levels for both non-productive process and manufacturing process, that eventually would also affect some organizational structures that ultimately can be understood as reengineering.

Legal requirements and responsibility for the environment require improved recyclability of car components. This can be achieved by a reduction in the variety of materials used, which can be separated after use. This is being demonstrated for wiring harnesses using a new hook and loop based fastening system. Easier assembly and disassembly, elimination of fixation holes in the car body, and improved serviceability can lead to considerable cost reductions. Field experience on test cars will be available at a later date.

Performance of two types of NOx adsorber catalysts, one based on Ba and the other based on Ba with alkali metals, was compared fresh and after thermal aging. Incorporation of sodium(Na), potassium(K) and cesium(Cs) into NOx adsorber washcoat containing barium significantly increases the NOx conversions in the temperature range of 350-600°C over that of the alkali metal free NOx adsorber catalysts. NOx performance benefit and HC performance penalty were observed on both engine dynamometer and vehicle tests for the “Ba+alkali metals” NOx adsorber catalysts. “Ba+alkali metals” NOx adsorber catalysts also demonstrate superior sulfur resistance with better NOx performance after repeated sulfur poisonings and desulfations over the “Ba based” NOx adsorber catalysts.

The development of an analytical model for multilayer stack subjected to temperature change is demonstrated here. Thin continuous layers of materials bonded together deform as a plate due to their differing coefficients of thermal expansion upon subjecting the bonded materials to the change in temperature. Applications of such structures can be found in the electronics industry (the study of warpage issues in printed circuit boards) or in the aerospace industry as (the study of laminated thin sheets used as skin structures for load bearing members such as wings and fuselage). In automotive electronics, critical high-power packages (IGBT, Power FETs) include several layers of widely differing materials (aluminum, solder, copper, ceramics) subjected to wide temperature cyclic ranges. Modeling of such structures by using three-dimensional finite element methods is usually time consuming and may not exactly predict the inter-laminar strains.

Delphi's Zero Resistance Technology (ZRT) is a revolutionary new product/process that enables the reduction of mass and volume from a traditional wiring assembly. ZRT is defined as a minimal (zero) resistance change over time. The ZRT product is an electrical/electronic connection system which provides a viable solution for high density and limited space wiring applications. The ZRT process is a semi-automated wiring harness manufacturing system with flexibility to produce harnesses to the customer demand.

Miniaturization is an important trend in many technology segments, once it can enable innovative applications generating new markets. This trend was begun in electronics industry after World War II and has spawned changes into automotive sector also. For Automotive Wiring Harness, miniaturization is clearly presented in most of the components, mainly because of its benefits like the potential of mass reduction, cost reduction and efficiency improvement. Furthermore the main voice of customer points to cable gauge reduction that represents a considerable challenge for connection manufacturing process due to quality control limitations presented by conventional crimp process for 0,35 [mm₂] cables and smaller. According to that, the scope of this article is to present, in details, a manufacturing process optimization for an alternative and more robust technology of joining copper stranded cables to tin brass terminals used on automotive wiring harness, Resistance Welding.

Several heater cores failed due to erosion by cavitation. After analysis, most of failures were explained by the presence of impurities in the heater core. It was then decided with the customer to use CFD simulation in order to prove that the cavitation was not caused by design concept of the tank. In this paper, we present the results of heater core simulations done in 2D and in 3D with Fluent. The objective is to simulate the pressure and velocity distribution within the heater core and to verify if the zones of low pressure are below the saturation vapour pressure of the fluid causing cavitation. In these areas, the deterioration of the tubes might occur due to erosion by cavitation.

A recent trend within the automotive industry has been an emphasis on the development of modular assemblies for future vehicle applications. This trend has created a need for the development of methods to predict the performance of modules within the vehicle environment. In particular, the development of system models that account for the interactions between components within a modular assembly is necessary to insure that a module is properly designed. This paper describes a finite element system model of a damper module as installed in a McPherson strut front suspension. The modeling techniques used to construct the components within the modular assembly are discussed. The results of a study of the structural behavior of a damper module model subjected to quasi-static loading conditions are presented. Additionally, the effects of changes in individual component specifications on the overall system response are considered and the results are displayed.

It is well known that hydrocarbon reduction during a cold start is a major issue in achieving ultra low emissions standards. This paper describes one of the possible approaches for reducing the cold-start hydrocarbon emissions by using a fast “light-off” planar oxygen sensor. The goal of this study was to verify the operation characteristics of Delphi's fast “light-off” planar oxygen sensor's (INTELLEK OSP) operating characteristics and the closed-loop performance for achieving improved hydrocarbon control for stringent emission standards. Tests were conducted in open-loop and closed-loop mode under steady and transient conditions using a 1996 model year 2.4-liter DOHC in-line 4-cylinder engine with a close-coupled catalytic converter. Overall performance of the OSP showed relatively quick reaction time to reach the operating temperature.

Optimization of the mechanical aspects of a heated conical oxygen sensor for desired performances, such as low heater power, good poison resistance, fast light-off, and broad temperature range, etc. was achieved with computer modeling. CFD analysis was used to model the flow field in and around a sensor in an exhaust pipe to predict the convection coefficients, poisoning, and switching time. Heat transfer analysis coupled with electrical heating was applied to predict temperature and light-off time. Results of the optimization are illustrated, with good agreements between modeling and testing.

This paper summarizes the results of an investigation of high risk, high potential technologies for hybrid vehicle drive applications and investigate potential solutions for the technical risk items associated with these technologies. The study consisted of the design, build, and test of different types of electric machines to understand their performance, efficiency, and manufacturability to develop hybrid vehicles with cost and performance similar to the present day IC engine based vehicles, but with lower emissions and better fuel economy. Machine technologies examined include synchronous reluctance, permanent magnet, and switched reluctance. Test data for various machine technologies is presented along with a discussion of the technical risk associated with each technology.