Existing Production Lines Research Articles

Phase‐Modulated Hierarchical Surface Structures by Interfering Laser Beams

AbstractA high‐energy laser interference direct modulation technique is proposed to develop surfaces for energy‐efficient performance based on microstructure and physical parameter control. By producing the surface features or particles at the nano to micron scale in an orderly and/or parallel manner with a lateral long‐range order, the surfaces can be configured for highly improved surface response for a host of properties, including wear and friction. Laser interference direct modulation can lead to an optimized composite of metallurgical (localized alloyed or composite regions) and topographic textures. The technique is rapid prototyping, low cost and one‐step method that can be well‐integrated into existing production lines without the need for any special atmosphere. It is usable for complex geometries of the components and the surface can be modulated for nano‐micro scale features on large areas. The present paper describes the principle behind the laser interference technique configured for surface modulation and provides the definitions of surface structures (features) evolved. Some examples of laser‐based surface modulation of materials systems are presented.

New approach to micro-joining by hot gas stream

The design and the realization of a novel approach in joining micro-parts of dimensions up to 300 μm in functional units (Hybrid MOEMS) using hot air stream is presented in this paper. A single-mode optical fiber used exemplary as a micro-part in first phase of experiments, has been positioned in mechanically made V-grooves and firmly joined to them by softening adhesives’ preforms in the solid state (polyurethane adhesive foil and hot-melt glue), with a hot air stream. Finite element analyses using the ANSYS program were performed in order to evaluate the temperature distribution along the heating tube and the nozzle, as well as within the air stream and the substrate on which the fiber was fixed. The advantages of this new approach are numerous: small size of system, low capital costs, applicability to many material combinations, easy integration in existing production lines, etc.

New concept for series manufacturing: Aluminium foam in industrial production

After a boom in research into the unique properties of aluminium foam, its implementation in series production and its integration into existing production lines, such as car body production, are now the focus of research and development activities. With its APM technology, Fraunhofer IFAM in Bremen presents a new process alternative that allows for simple, flexible and cost-effective part production. Many examples demonstrate the application potential of metal foam, many aspects of which have already been implemented.

Improvement of weldability of TRIP steels by use of in‐situ pre‐ and post‐heat treatments

Low alloy TRIP‐aided steels are very interesting for the automotive industry as they combine both a high strength and an excellent formability. Though the actually developed TRIP steels can be considered as low alloyed when compared to the first generations of steels exhibiting TRIP effect, due to their chemical composition, they still exhibit a quite high carbon equivalent. This is particularly detrimental for the weldability of those materials. After solidification, welds are very hard and can show a brittle behaviour. The hardness of the heat affected zone of the welds can even exceed 500HV and cold cracking phenomena is prone to occur.In the automotive industry, spot welding is the main joining process. During spot welding of TRIP steels, the interface between the plates can act like a notch and promote fracture of the weld. This is particularly dangerous when brittle welds are submitted to peel stresses. The aim of the paper is to demonstrate that a careful choice of the process parameters can significantly improve the resistance of the welds. The selection of the welding cycle parameters is far from being an easy task as many different parameters are involved. Therefore, a design of experiment methodology (DOE) was chosen to optimise the welding cycle for a cold‐rolled TRIP steel with a tensile strength above 700 MPa. Mechanical properties of the welds were significantly improved by use of pre‐ and post‐heat treatments. Those improved welding cycles were realised without excessive extension of the total weld cycle on a conventional spot welding machine. This means that the optimised welds can be obtained in the existing production lines without any additional investment or significant decrease in productivity.

Ceramic wall materials using glass waste

The effect of glass waste on the properties of ceramic wall materials is investigated, the optimum batch composition is developed, and an experimental lot of bricks is produced on existing production lines without significant modifications of the technological conditions. The fundamental possibility of utilization of household waste glass is demonstrated.

406 クラスター分析による生産ラインの再設計の支援に関する研究

Much emphasis has been given to minimize the time not only for design and manufacturing of products but also for development of production lines, in order to deliver products to market as soon as possible. However, planning, design and evaluation processes of production lines are very complicated, and individual engineers carry out the production lines' design based on their own experiences. It is now eagerly required to establish systematic methods and support tools, in order to support all the engineering processes for the planning, design, evaluation and redesign of the production lines. The objective of the research is to establish systematic methods and computerized support systems based on cluster analysis, in order to deal with the redesign of the existing production lines.

Toxic Hepatitis from Dimethylacetamide.

Two cases of toxic hepatitis from dimethylacetamide (DMAC) occurred among 25 employees on a new acrylic-fiber production line at a western U.S. manufacturing plant. Interesting features of these cases include: 1) inadequate personal protective equipment (PPE) for dermal exposures, resulting in skin penetration during maintenance and repair procedures; 2) the subjects of these case reports are female; all workers at the manufacturer's European plant were male, and DMAC-related liver dysfunction had not been encountered at that site; 3) the new American production line required more frequent maintenance and repair work than existing production lines at the European parent company, resulting in greater opportunities for DMAC exposure. Hepatotoxicity due to dermal absorption of DMAC and other amide-type solvents deserves special consideration in industrial settings.

Collective fabrication of microsystems compatible with CMOS through the CMP service

One of the main obstacles to starting microsystems is the fact that particular and hence costly processes are needed. In order to reach affordable prices and a high flexibility, microsystems should whenever possible be conceived such that they can be realized on existing production lines for microelectronics, with additional post-processing for micro-system-specific 2D and 3D structures, e.g. through Multi-Project-Wafer services as proposed by the CMP service. Furthermore, this approach allows to integrate the microelectronics, needed in most microsystems, on the same chip. This paper describes the main micromachining methods, including design theory, implementation and recommendations. It presents the results obtained of microelectronics compatible fabrication methods (CMOS bulk and surface micromachining) and microelectromechanical systems that have been fabricated using these technologies. It also details the CAD tools support.

The resource recovery industry

Views of the resource recovery industry's present and future roles are summarized. Most industries have entered the resource recovery business to expand existing production lines, to promote concomitant services, and to broaden raw materials or energy-supply bases. Most firms will provide technology to solve the waste problem only if it can make a profit. Thirty-to-forty-thousand-tons-per-day facilities are expected by 1982. Prime industrial concerns are legal conflicts, financing, and government policy.