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This paper aims to detail the qualification of alternative substrate materials and reliability aspects for quad flat no lead (QFN) packages for highly stressed electronic devices, e.g. for use in automotive applications.

Detailed information is given on the advanced climatic and mechanical requirements that electronic devices have to withstand during life cycle testing to qualify for the automotive industry. Studies on the suitability of high‐temperature thermoplastics as substrate materials for printed circuit boards and the qualification of QFN packages for advanced requirements are described. In addition, information on cause‐effect relationships between thermal and vibration testing are given.

With respect to adhesion of metallization on high‐temperature thermoplastics and the long‐term stability of the solder joints, these substrate materials offer potential for use in electronic devices for advanced requirements. In addition, the long‐term stability of the solder joints of QFN packages depends on the design of the landings on the PCB and the separation process of the components during manufacturing.

The paper covers only a selection of possible high‐temperature thermoplastic materials that can be used in electronics production. Also, this paper has a focus on the new packaging type, QFN, in the context of qualification and automotive standards.

The paper details the requirements electronic devices have to meet to be qualified for the automotive industry. Therefore, this contribution has its value in giving information on possible substrate alternatives and the suitability for the usage of QFN components for highly stressed electronic devices.

THERE have been rapid developments in the evolution of engineering thermoplastics for use by the automobile industry. One of the most recent, which provides a wide spectrum of properties for the automotive industry, is the result of a technical breakthrough in thermoplastic polyethylene terephthalate (PETP) polyester resins for engineering applications.

The paper presents results of a pilot project on technological innovation of main flexible components for automotive suspension systems, that are coil springs and stabilizer bars. Current technology has been described and related problems have been outlined. In order to fulfil features such as compactness, lightness and environmentally conscious design, solutions based on new forms, materials and manufacturing processes have been proposed. Improvements in weights, dimensions, noiselessness, corrosion and fatigue strength, environmental effects, have been all assessed, keeping a quite low project cost (around $3 million).

The excellent specific stiffness and strength of carbon fibre reinforced composites make them especially interesting for applications in rotating machines. Unfortunately, these materials have the disadvantage that their manufacturing process is labour‐intensive, and thus slow and expensive. This drawback is overcome by the highly automated thermoplastic fibre placement process, in which impregnated thermoplastic tape is heated and then consolidated in situ under pressure. ABB has implemented the process in the laboratory with a six‐axis robotic system and is using it to develop new components for turbomachinery. The process is also of interest for applications in the aircraft and automotive industries.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Application of the engineering design optimization methods and tools to the design of automotive body‐in‐white (BIW) structural components made of polymer metal hybrid (PMH) materials is considered. Specifically, the use of topology optimization in identifying the optimal initial designs and the use of size and shape optimization techniques in defining the final designs is discussed. The optimization analyses employed were required to account for the fact that the BIW structural PMH component in question may be subjected to different in‐service loads be designed for stiffness, strength or buckling resistance and that it must be manufacturable using conventional injection over‐molding. The paper demonstrates the use of various engineering tools, i.e. a CAD program to create the solid model of the PMH component, a meshing program to ensure mesh matching across the polymer/metal interfaces, a linear‐static analysis based topology optimization tool to generate an initial design, a nonlinear statics‐based size and shape optimization program to obtained the final design and a mold‐filling simulation tool to validate manufacturability of the PMH component.

The printed circuit industry is on the verge of witnessing a change in structure, brought about by the advent of Moulded Thermoplastic PCBs and accompanying electroless plating technology. Currently all fabricators use essentially similar technology and pressed laminates, except a few innovative companies who are exploring the new technology for moulded thermoplastic printed circuit boards. The new moulded PCBs (MPCBs) have many claimed advantages over traditional boards, such as: lower production costs through faster moulding fabrication; more precise drilled holes and board dimensions; custom designed hole shape and board shape; integral moulding of board and device enclosure; higher thermal stability and dimensional stability; better dielectric properties for reduced cross‐talk; and adaptable integration of circuit design and components. Certainly the industry will not change overnight, but, as changes take place, the traditional materials will be replaced by new polymers, chemicals and equipment, as MPCBs are introduced into relevant fields of application. Some firms believe that MPCBs are only a small specialised market, while others feel that they will eventually replace many of the traditional PCB constructions of today. Chem Systems has analysed these views and prepared a study which will help to discover the real impact of MPCBs on designers, fabricators and suppliers on a worldwide basis.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.