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Technical Paper

New Materials and Experiences for the Industrialization of Pu Structural Rim Technology

1996-04-01
91A122
Processes involving use of reactive polymers received recently considerable attention also for producing components suitable for automotive structural applications. In particular polyurethane structural RIM technology seems to be the route of choice in terms of productivity, reliability and physico- mechanical performances in order to fit the automotive industry needs in the production of parts requiring superior load bearing properties. In this frame the development of long pot life snap-cure resins, fast and effective reinforcement preforming techniques as well as the development of computerized provisional processing methodologies are of paramount importance in view of industrialization of the technology. In this paper a description of the work carried out by Enichem Montedipe and Montedison is given. In particular a new family of PU systems, based on special isocyanate variants, is reported.
Technical Paper

Integration and Validation of Sheet Metal Forming Simulation Computer Programs Into the Design Process

1996-04-01
91A121
In order to improve the design of drawn parts and to reduce the number of trial and error tests, Renault has undertaken the development and the validation of various finite element procedures and codes. This paper describes the function of each software and its level of integration into the design process. One of them is already an operational tool used be planners whilst the others are still in the validation phase. Selected examples show typical applications of the computer programs on automotive parts.
Technical Paper

Particulate Reinforced Aluminum Matrix Composites Obtained By Indirect Squeeze-Casting

1996-04-01
91A115
Indirect squeeze casting technology is one of the most attractive fabrication techniques of near net shape components constituted by aluminum matrix composite (AMC) materials. AMCs reinforced with both continuous and discontinuous ceramic elements have been mainly produced by infiltration of porous preforms. Nevertheless, a further promising production route offered by this technique is given by the possibility to employ ingots of pre-reinforced aluminum alloys containing ceramic particles (silicon carbide or alumina); ingots are remelted and, under suitable operative conditions, high quality composite castings of simple and complex shape are produced by squeeze casting. The present paper describes the results of an extensive experimental work carried out by Alures-Centro Tecnico Porcessi on a pilot plant scale employing a vertical squeeze casting machine with a clamping force of 315 tons.
Technical Paper

Crash Performance of Rtm Composites for Automotive Applications

1996-04-01
91A120
This paper describes the experimental activity carried out at Aerospace Engineering Department of Politecnico di Milano about energy absorption capability of glass-epoxy RTM specimens, representative of automotive crash front structure sub-components. After the analysis of some automotive crashworthiness aspects, especially relevant to the structural adoption of composite materials, the specimen used and the technological route to produce them are described. Then experimental arrangements, test procedure and measurement technique, relevant to static and crash test are presented. Finally test results, reported in the form of numerical values, diagrams and high-velocity films are shown and critically commented.
Technical Paper

Glass Reinforced Thermoplastic Composites: Effects of Ribs and Different Types of Reinforcement on the Characteristics of the Molded Part

1996-04-01
91A119
Compression molding of thermoplastic sheets, consolidated or non- consolidated, reinforced with glass fibers (GMT, GRT) is applied as an economic production process in the automotive industry. The aim of this work is to evaluate how the physical and mechanical strength characteristics depend on the presence or absence of ribs and how component performance may be changed by modifying the molding parameters, altering the content and orientation of the reinforcement fibers in the ribbed areas. For this purpose, two statistical designs will be considered, the first carried out on a box type component without ribs, the second on the same component with a set of internal ribs. Two different materials with a PP matrix will be tested, a GMT reinforced with continuous random glass fibers and a 12 mm random glass fibers composite.
Technical Paper

Thermomechanical Behavior and Wear Resistance of Whisker Or Particle Reinforced Ceramics

1996-04-01
91A107
Ceramic composite materials have been intensively studied during the last years. Particles and whisker reinforcement have shown the simultaneous advantage to allow the preparation of composite materials by conventional processing and to lead, when under optimum conditions, to dramatic toughening and strengthening. Since wear resistance of brittle material have been shown to be related to both hardness and toughness, composite materials with improved were resistance have been developed for cutting tools or bearing applications. However the mechanism responsible for toughening is of major important for wear resistance effectiveness. We have therefore reviewed the main mechanisms before presenting some examples of composites materials for wear resistance applications.
Technical Paper

Toothed Couplings for Diesel Engines: An Example of Steel Substitution With Fiber Reinforced Plastics

1996-04-01
91A100
The replacement with plastic of an important component, formerly in steel, in the timing drive of a heavily duty diesel engine has been studied and realized. The substituted part is the toothed coupling connecting the injection pump to the timing drive. Torque that stresses the coupling has been measured with laboratory tests. The tooth stresses have been calculated with FEM analysis. Finally, fatigue tests have been carried out directly on the engine at different loadings. The test results are consistent with the predicted behavior of this component.
Technical Paper

Actuation and Fastening With Shape Memory Alloys in the Automotive Industry

1996-04-01
91A103
As a result of a phase transformation, shape memory alloys can change their shape when the temperature changes. This unusual effect can be utilized in actuation and fastening components for automotive applications. Springs made from Ni-Ti shape memory alloys change their rate in a predetermined temperature range due to a significant change in the elastic modules of the material. They can be used as sensor-actuators in pressures control valves or oil cooler by-pass valves in automatic transmissions or to compensate for oil viscosity changes in shock absorbers or thermal expansion of dissimilar materials in gear boxes. If the recovery is constrained, i.e., shape memory element is physically prevented from returning into its original shape, a potentially high stress is generated. This effect is used in fastener rings. Fasteners made from Ni-Ti alloys provide high reliability and easy installation for braid terminations, locating of shaft mounted components, connectors and hose clamps.
Technical Paper

Ceramic Coating for Aluminum Engine and Components

1996-04-01
91A105
The trend toward lighter vehicles for improved performance has recently introduced the use of aluminum and plastic materials for vehicle bodies and drive trains. In particular, the aluminum alloy block foar engine application is certain to reappear. The soft aluminum cylinder liner will require additional treatment before acceptance. Three possible approaches appear to solve the aluminum cylinder liner dilemma. These approaches are: 1) use of high silicon aluminum such as the 390 aluminum; 2) insert or cast steel liners into the aluminum engine block; and 3) ceramic coat the low cost standard aluminum engine block. Each has known advantages and disadvantages. It is the purpose of this paper to present the merits of option 3, the ceramic coated aluminum cylinder bore, from the standpoint of low weight, cost, and tribological effectiveness. The advantages of approaches 1) and 2) are obvious. High temperature after treatment of the ceramic engine components is not required.
Technical Paper

Engineering Plastics for Novel Automotive Applications

1996-04-01
91A093
Not only have engineering thermoplastics secured an accepted place in automotive manufacture, but also their penetration of areas traditionally the sole domain of metals, is growing. One group of materials in particular is driving this trend; that of advanced thermoplastic composites. Used primarily in non-appearance, semi-structural parts, thermoplastic composites are opening the way for engineering polymers to be used in large components such as tailgates, technical fascia's or front end modules, side doors and bonnets, amongst many other novel applications whose engineering criteria could previously be met only by steel. This paper will look at both the new opportunities for engineering plastics in automotive applications and at the materials capable of economically satisfying their demands
Technical Paper

A Fatigue Data-Bank Developed as a Design Support for Structures in Composite Materials

1996-04-01
91A092
A data bank developed to give a concrete help to the designer concerned with fatigue-prone structures made of composite materials is described. The data bank not only collects the available results of fatigue tests on these materials, but also makes easy their statistical analysis and comparison for design purposes. It is then believed to constitute also an useful research instrument for the development of design rules for well defined classes of composite materials.
Technical Paper

Fe Model Adjustment of a Composite Material Car-Body By Means of Experimental Modal Analysis on the Prototype

1996-04-01
91A095
A procedure adopted to verify and update the finite elements model of an electric powered car-body manufactured from composite materials is described. Experimental results, obtained from modal testing of the prototype, are used in order to identify and correct discrepancies in the FE model. The availability of a highly reliable FE model allows to simulate structural modifications by computer, optimizing the use of composites and reducing in the same time at minimum prototypes construction. The approach followed suggests a possible remarkable reduction in product development costs and duration. The work has been performed within a larger program for the development of thermoplastic composite materials, with particular attention to transportation market.
Technical Paper

Future Trends in Applications of Structural Composite for Automotive

1996-04-01
91A097
The paper outlines the future trends for structural applications of composite in automotive. RTM, SMC and S-RIM seem to be the most promising technologies in this field. Parts made with epoxy resins in resin transfer molding technology have very good mechanical properties that allow them to be suitable for chassis applications coupled with steel parts. The SMC compounded with Derakane resin shows very good qualities in terms of temperature resistance and a reasonable high volume of production. The last technology rising is the S- RIM that seems to be very promising because of its short cycle time coupled with mechanical properties. Several examples of applications of these different technologies are showed in the paper; some of those are already in production some others are in an advanced phase of development.
Technical Paper

Pultrusion Technology for the Transportation Industry

1996-04-01
91A099
The utilization of the pultrusion process for the manufacturing of components and structures for the transportation industry is discussed. Both the characteristics and capabilities of the process and the properties of pultruded composites are reviewed. The most important characteristics of this process is its capability of producing cost effective composite products which exhibit all the features of other composites. The benefits of this technology are demonstrated by a variety of applications for different industries together with the more recent developments for the transportation industry.
Technical Paper

Practical Applications of Composite Exotic Hybrids and Their Structural Use in Vehicles

1996-04-01
91A098
An overview of high strength thermoset and thermoplastic composites will provide a basis of comparison with exotic hybrid composites. A specific theoretical application for a very high strength unibody application will be presented and test results evaluated. A critical overview of immediate applications will be presented and evaluated. In conclusion, it will be suggested that a uniform standard of performance be established for the practical application's requirements for these materials
Technical Paper

The Prediction of Shrinkage and Warpage in Plastics Injection Molded Auto Parts

1996-04-01
91A088
The article emphasizes the effect of flow on dimensional stability, mechanical properties and surface finish, and the close coupling of dimensional stability and mechanical properties. Warpage is the result of the balance between the structural stiffness of the part and the stress pattern resulting in variation in shrinkage due to area shrinkage, orientation, and thermal effects. The practical solution to warpage depends on the use of software to isolate the basic causes of warping which then leads to a logical solution procedure.
Technical Paper

Australian Initiatives in Traffic Management and Energy - Vehicle Parameters and Interactions

1988-03-01
871158
This paper reviews the interactions between vehicle and road designers, particularly in the area of fuel consumption related to traffic management. The need for increased interaction between vehicle and road designers is illustrated in the cases of truck traffic performance, truck technology, information technology in cars, car performance, speed control and road information. Fuel consumption models developed at the Australian Road Research Board are described for the purposes of traffic management analysis for intersections, road links and broad urban studies. These models are a major step towards appropriate choice of traffic control systems, but need accurate estimates of vehicle performance characteristics in real traffic.
Technical Paper

Correlation of Bending Strength and Errors of Helical Gear

1988-03-01
871223
CORRELATION OF BENDING STRENGTH AND ERRORS OF HELICAL GEAR has not been clarified sufficiently even now. As the investigation by using only experimental method is not sufficient and so the analytical method of obtaining gear bending strength has been developed by one of the authors. Hence, the correlation of bending strength and errors, especially in the aspect of the direction of pressure angle error and tooth trace error, is clarified by this analytical method which was verified by some experiments. And by further investigations, it is confirmed that the helical gear is tougher against the negative pressure angle error, and the fine module gear is sensitive against the errors.
Technical Paper

Development of STORM Series Diesel Engine (D1146, D1146T, D2366, D2366T)

1988-03-01
871218
For the purpose of satisfying today's market demands, new 8 and 11 liter diesel engines, named "STORM" series, have been developed and moved into production in 1986. Based on the predecessors which have been produced since 1975, the development of the STORM series aimed high performance, low emission, long life-time and low operating costs. In order to consult customers' convenience, exchangeability of engine parts and commonality of vehicle installations with the former engines had to be maintained. This paper describes the development work of STORM engines, and the design aspects and performance characteristics of these engines.
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