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Technical Paper

"Nickel electroformed" tools development through stereolithography (SLA) for sheet metal forming~An evaluation study

2000-06-12
2000-05-0272
Currently, advancements in Rapid Prototyping (RP) technologies have led to considerable amount of research activities and has been playing a major role in the area of tooling development for which Rapid Tooling (RT) term was coined. While rapid prototyping techniques are employed to make prototype tools, the basic idea of the rapid tooling is to produce prototype and zero series parts by using prototype tools so the parts truly represent the future production. This paper will present an evaluation of a RP and RT technique in developing tools (punch and dies) for sheet metal forming, which had been manufactured and tested. Both punch and die have been manufactured by combining Stereolithography (SL), RP technique, with nickel electroforming process. The stereolithography technique that had been utilized in developing models for the tools had been built with modeling pattern called Accurate Clear Epoxy Solid (ACES).
Technical Paper

<PP/SEBS> Compounds: Sealing an Easier Future for Automotive Designers and Specifiers

2002-07-09
2002-01-1997
There is a definite trend toward the increasing use of “Glass Encapsulation Technology” in the automotive industry. In this technology a glass object such as a window is placed within a mould and an elastomer is injected around the window giving a tight sealing system. A wide variety of materials are currently used as the sealing materials in either static or semi-static encapsulated glazing systems, including a wide range of “elastomers”. New thermoplastic elastomer compounds are being developed that are characterized by their consistent properties; including high melt-fluidity, very good surface appearance, sealing properties, and resistance to weathering. Compound performance is highly dependent on formulation variables as well as the chemistries of the base materials. KRATON® SEBS polymers1 are block copolymers of styrene and ethylene/butylene.
Technical Paper

(Particle) Emissions of Small 2-& 4-Stroke Scooters with (Hydrous) Ethanol Blends

2010-04-12
2010-01-0794
The objectives of the present work are to investigate the regulated and unregulated (particle) emissions of a classical and modern 2-stroke and a typical 4-stroke scooter with different ethanol blend fuels. There is also comparison of two different ethanol fuels: pure ethanol (E) *) and hydrous ethanol (EH) which contains 3.9% water and is denatured with 1.5% gasoline. Special attention is paid in this research to the hydrous ethanol, since the production costs of hydrous ethanol are much less than those for (dry) ethanol. The vehicles are with carburettor and without catalyst, which represents the most frequent technology in Eastern Asia and offers the information of engine-out emissions. Exhaust emissions measurements have been performed with fuels containing ethanol (E), or hydrous ethanol (EH) in the portion of 5, 10, 15 and 20% by volume. During the test systematical analysis of particle mass (PM) and nano-particles counts (NP) were carried out.
Journal Article

0W-16 Fuel Economy Gasoline Engine Oil Compatible with Low Speed Pre-Ignition Performance

2017-10-08
2017-01-2346
It has been long established fact that fuel economy is a key driving force of low viscosity gasoline engine oil research and development considered by the original equipment manufacturers (OEMs) and lubricant companies. The development of low viscosity gasoline engine oils should not only focus on fuel economy improvement, but also on the low speed pre-ignition (LSPI) prevention property. In previous LSPI prevention literatures, the necessity of applying Ca/Mg-based detergents system in the engine oil formulations was proposed. In this paper, we adopted a specific Group III base oil containing Ca-salicylate detergent, borated dispersant, Mo-DTC in the formulation and investigated the various effects of Mg-salicylate and Mg-sulfonate on the performance of engine oil. It was found that Mg-sulfonate showed a significant detrimental impact on silicone rubber compatibility while the influence from Mg-salicylate remains acceptable.
Technical Paper

1.8L Sierra-Mondeo Turbo-Diesel Valvetrain Friction Reduction Using a Solid Film Lubricant

1994-10-01
941986
A 1.8L turbocharged diesel engine valvetrain friction was investigated, and the effectiveness of using a solid film lubricant (SFL) coating in reducing friction was determined throughout the operable speed range. This valvetrain design features direct acting mechanical bucket valve lifters. Camshaft journal bearing surfaces and all camshaft rubbing surfaces except lobe tips were coated. The direct acting bucket shims were etched with a cross hatch pattern to a depth sufficient to sustain a SFL film coating on the shim rubbing surfaces subjected to high surface loads. The SFL coated valvetrain torque was evaluated and compared with uncoated baseline torque. Coating the cam bearing journal surfaces alone with II-25D SFL reduced valvetrain friction losses 8 to 17% for 250 to 2000 rpm cam speed range (i.e. 500 - 4000 rpm engine speed). When bucket tappet and shims were also coated with the SFL, further significant reductions in coated valvetrain friction were observed.
Technical Paper

100% Post-Consumer Recycled Nylon 6: Repolymerized Resin Provides Full Mechanical, Physical, & Aesthetic Properties

2000-03-06
2000-01-1394
The increased use of recycled resins can create a dilemma for automotive designers. On the one hand, there is a growing initiative to increase recycled materials content on vehicles, globally. On the other hand, traditional methods of recycling polymeric materials -both thermoplastics and thermosets - can lead to degradation of engineering, mechanical, processing, and / or aesthetic properties of the resin. In an era where quality rules, this situation forces designers to accept a much lower percentage of recyclate than they might otherwise wish to use or risk unacceptable property loss in molded parts - something no automaker can “afford ” for long. Hence, a valuable feedstream of materials (polymers) often ends up destined for a landfill once many consumer products are broken down and more easily reusable or recyclable materials are salvaged. As a case in point, each passenger car built globally contains an average of 15 - 20 kg of nylon polymers.
Technical Paper

100,000 Miles of Fueling 5.9L Cummins Engines with 100% Biodiesel

1996-10-01
962233
Two Cummins B5.9L engines were fueled with 100% biodiesel in excess of 48 months by the Agricultural Engineering Department at the University of Missouri-Columbia. The engines used to power Dodge pickups. The engine lubricating oil was sampled at 1000 mile intervals for analysis. Statistical analysis of the engine lubricating oil indicated that the wear metal levels in the lubricating oil were normal. A reduction in power was noted when the engines were tested using a chassis dynamometer. The 1991 pickup has been driven 110,451 km and the 1992 pickup has been driven approximately 177,022 km. The pickups averaged 6.9 km/L. Engine fuel efficiency and material compatibility issues are addressed in the paper.
Technical Paper

100,000-Mile Evaluation of Transit Buses Operated on Biodiesel Blends (B20)

2006-10-16
2006-01-3253
Nine identical 40-ft. transit buses were operated on B20 and diesel for a period of two years - five of the buses operated exclusively on B20 (20% biodiesel blend) and the other four on petroleum diesel. The buses were model year 2000 Orion V equipped with Cummins ISM engines, and all operated on the same bus route. Each bus accumulated about 100,000 miles over the course of the study. B20 buses were compared to the petroleum diesel buses in terms of fuel economy, vehicle maintenance cost, road calls, and emissions. There was no difference between the on-road average fuel economy of the two groups (4.41 mpg) based on the in-use data, however laboratory testing revealed a nearly 2% reduction in fuel economy for the B20 vehicles. Engine and fuel system related maintenance costs were nearly identical for the two groups until the final month of the study.
Technical Paper

11 Rules of Design for Manufacturing when Producing Pre-Impregnated Carbon Fiber-Reinforced Plastic Components - an Application at SAAB Aerostructures

2016-09-27
2016-01-2124
Carbon fiber-reinforced plastic (CFRP) is one of the most commonly used materials in the aerospace industry today. CFRP in pre-impregnated form is an anisotropic material whose properties can be controlled to a high level by the designer. Sometimes, these properties make the material hard to predict with regards to how the geometry affects manufacturing aspects. This paper describes eleven design rules originating from different guidelines that describe geometrical design choices and deals with manufacturability problems that are connected to them, why they are connected and how they can be minimized or avoided. Examples of design choices dealt with in the rules include double curvature shapes, assembly of uncured CFRP components and access for non-destructive testing (NDT). To verify the technical content and ensure practicability, the rules were developed by, inter alia, studying literature and performing case studies at SAAB Aerostructures.
Technical Paper

175°C-Capable Thermoplastic Elastomers for Automotive Air Management and Sealing Applications

2007-11-28
2007-01-2576
Flexibility, oil resistance, and the need for heat resistance to 150°C-plus temperatures have traditionally limited automotive design engineers to two options - thermoset rubber or heat-shielding conventional thermoplastic elastomers (TPE). Both of these options present limitations in part design, the ability to consolidate the number of components in a part of assembly, and on total cost. This paper presents a class of high-performance, flexible thermoplastic elastomers based on dynamically vulcanized polyacrylate (ACM) elastomer dispersed in a continuous matrix of polyamide (PA) thermoplastic. These materials are capable of sustained heat resistance to 150°C and short-term heat resistance to 175°C, without requiring heat shielding. Recent advancements in blow molding and functional testing of the PA//ACM TPEs for automotive air management (ducts) and underhood sealing applications will be shown.
Technical Paper

1962 passenger-car engineering trends

1962-01-01
620066
The phenomenal success of the small car is leading to many engineering changes in the automobile industry. It has brought increased emphasis on weight reduction on both small and full-size cars. Improving reliability and designing to eliminate grease fittings have also become important objectives.
Technical Paper

1979 Firebird - An Advanced (Part 581) Soft Bumper System

1979-02-01
790335
Weight and performance characteristics of the 1979 Pontiac Firebird soft bumper system are compared to those for a typical new (1979) metal/hydraulic design to evaluate the effects of the new standard. This study demonstrates the changing competitive environment in the automotive bumper market due to the introduction of the Part 581 Standard. The deep soft bumper concept is also discussed including its potential for achieving weight reductions in future elastomeric bumper systems.
Technical Paper

2-Ply Windshields: Laboratory Impactor Tests of the Polyurethane Construction

1995-02-01
950048
A test program was conducted to characterize the impact response of an experimental 2-ply windshield construction with a polyurethane (PUR) plastic inner layer. Windshield impact tests were conducted using a linear impactor test facility. Principle among the findings was that the impact response of prototype PUR 2-ply windshields does not differ that significantly from that of baseline 3-ply HPR (High Penetration Resistance) windshields for the subcompact vehicle geometry tested. However, the impact responses of both PUR 2-ply and 3-ply HPR subcompact vehicle windshields were found to be highly variable. Average performance of either construction could thus be enhanced if ways could be found (and then implemented) to reduce this variability.
Technical Paper

2-Ply Windshields: Laboratory Impactor Tests of the Polyvinyl Butyral/Polyester Construction

1995-02-01
950047
A test program was conducted to characterize the impact response of an experimental 2-ply windshield construction with a polyvinyl butyral / polyester (PVB/PET) inner plastic laminate. Windshield impact tests were conducted using a linear impactor test facility. Principal among the findings was that the measured impact response of prototype PVB/PET 2-ply windshields was highly variable. Average performance of this construction could thus be improved if ways could be found (and then implemented) to reduce this variability.
Technical Paper

2004 Nissan 3.5L Cam Cover Material Study: Aluminum, Magnesium and Composite

2005-04-11
2005-01-0727
The present study compares the NVH performance of three different materials used on cam covers in automobiles, Aluminum (Al), Magnesium (Mg) and Thermoplastic (TP). The cam cover design used for this comparison was the 2004 Nissan Maxima 3.5L production cam cover which is made of a thermoplastic (TP). The Al and Mg covers for this study were created by sandcast, due to time constraints, via laser scanning techniques using the 2004 Nissan Maxima 3.5L production thermoplastic cover design. Note that sand-cast covers generally provide a less quiet sound field than the standard casting method. The Nissan production cover comes with a production baffle made of a similar material as the cover. Testing was conducted with and without the production baffle for all covers. The study was conducted for the production boundary condition of a non-isolated cover and a Freudenberg-NOK (FNGP) partially isolated cover. Isolated bolt assemblies using elastomeric grommets were used to isolate the cover.
Technical Paper

2013 SRT Viper Carbon Fiber X-Brace

2013-04-08
2013-01-1775
The 2013 SRT Viper Carbon Fiber X-Brace, styled by Chrysler's Product Design Office (PDO), is as much of a work of art as it is an engineered structural component. Presented in this paper is the design evolution, development and performance refinement of the composite X-Brace (shown in Figure 1). The single-piece, all Carbon Fiber Reinforced Plastic (CFRP) X-Brace, an important structural component of the body system, was developed from lightweight carbon fiber material to maximize weight reduction and meet performance targets. The development process was driven extensively by virtual engineering, which applied CAE analysis and results to drive the design and improve the design efficiency. Topology optimization and section optimization were used to generate the initial design's shape, form and profile, while respecting the package requirements of the engine compartment.
Technical Paper

26 Development of “BF-Coat” for Snowmobile Piston

2002-10-29
2002-32-1795
The pistons in a snowmobile engine are subjected to severe temperature conditions not only because snowmobiles are operated in extremely cold temperatures but also because the engine has a high output per unit volume of approximately 150kW/liter. The temperature of the piston top may go from -40°C (when a cold engine is started) to 400°C or higher (when the engine is running at full load). When the piston and cylinder inner wall are cold, the performance of the lubricating oil drops; when they are hot, scuffing may be produced by problems such as tearing of the oil film between the piston and cylinder. When the engine is run at full load for a long time, moreover, the piston is subjected to prolonged high-temperature use, which is conducive to the production of piston boss hole abrasion and ring groove adhesive wear.
Standard

265°F Vacuum Cure, Epoxy Prepregs

2017-11-08
WIP
AMS6566
The purpose of this specification is to allow procurement of a defined material corresponding to statistically derived material properties published in CMH-17. This material is intended for use in laminate applications with a service temperature up to 180 °F. They are typically used in structural applications requiring high strength and stiffness. This is the base specification and it will have one slash/detail specs.
Standard

265°F Vacuum Cure, Epoxy Prepregs Type 42, Class 2, Grade 193, Style 12K-193-SFP-OSI

2017-11-10
WIP
AMS6566/1
The purpose of this specification is to allow procurement of a defined material corresponding to statistically derived material properties published in CMH-17. This material is intended for use in laminate applications with a service temperature up to 180 °F. They are typically used in structural applications requiring high strength and stiffness. This is the base specification and it will have one slash/detail specs.
Standard

265°F, Autoclave Vacuum Bag Cure, Epoxy Prepreg, Type 33, Class 1, Grade 148, Intermediate Modulus Carbon Fiber

2017-11-10
WIP
AMS6568/1
The purpose of this specification is to allow procurement of a defined material corresponding to statistically derived material properties published in CMH-17. This material is intended for use in laminate applications with a service temperature up to 180 °F. They are typically used in structural applications requiring high strength and stiffness. This is the base specification and it will have three slash/detail specs.
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