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FutureSteelVehicle's (FSV) objective is to develop detailed design concepts for a radically different steel body structure for a compact Battery Electric Vehicle (BEV). It also will identify structure changes to accommodate larger Plug-In Hybrid (PHEV) and Fuel Cell (FCEV) vehicle variants. The presentation will demonstrate seven optimized structural sub-systems that contribute to the program's 35 percent mass reduction goals and meet its safety and life cycle emissions targets. It will explain the advanced design optimization process used and the resulting aggressive steel concepts. Presenter Jody R. Shaw, US Steel

The conventional forming limit curve (FLC) has been widely and successfully used as a failure criterion to detect localized necking in stamping. However, in stamping advanced high strength steels (AHSS), under certain circumstances such as stretching-bending over a small die radius, the sheet metal fails much earlier than predicted by the FLC. This type of failure on the die radius is commonly called “shear fracture.” In this paper, the laboratory Stretch-Forming Simulator (SFS) and the Bending under Tension (BUT) tester are used to study shear fracture occurring during both early and later stages of stamping. Results demonstrate that the occurrence of shear fracture depends on the combination of the radius-to-thickness (R/T) ratio and the tension/stretch level applied to the sheet during stretching or drawing. Based on numerous experimental results, an empirical shear fracture limit curve or criterion is obtained.

One of the issues in stamping of advanced high strength steels (AHSS) is the stretch bending fracture on a sharp radius (commonly referred to as shear fracture). Shear fracture typically occurs at a strain level below the conventional forming limit curve (FLC). Therefore it is difficult to predict in computer simulations using the FLC as the failure criterion. A modified Mohr-Coulomb (M-C) fracture criterion has been developed to predict shear fracture. The model parameters for several AHSS have been calibrated using various tests including the butter-fly shaped shear test. In this paper, validation simulations are conducted using the modified (M-C) fracture criterion for a dual phase (DP) 780 steel to predict fracture in the stretch forming simulator (SFS) test and the bending under tension (BUT) test. Various deformation fracture modes are analyzed, and the range of usability of the criterion is identified.

Gas Metal Arc Welding (GMAW) is widely employed for joining relatively thick sheet steels in automotive body-in-white structures and frames. The GMAW process is very flexible for various joint geometries and has relatively high welding speed. However, fatigue failures can occur at welded joints subjected to various types of loads. Thus, vehicle design engineers need to understand the fatigue characteristics of welded joints produced by GMAW. Currently, automotive structures employ various advanced high strength steels (AHSS) such as dual-phase (DP) and transformation-induced plasticity (TRIP) steels to produce lighter vehicle structures with improved safety performance and fuel economy, and reduced harmful emissions. Relatively thick gages of AHSS are commonly joined to conventional high strength steels and/or mild steels using GMAW in current body-in-white structures and frames.

Development of reliable magnesium (Mg) to steel joining methods is one of the critical issues in broader applications of Mg in automotive body construction. Ultrasonic spot welding (USW) has been demonstrated successfully to join Mg to steel and to achieve strong joints. In this study, corrosion test of ultrasonic spot welds between 1.6 mm thick Mg AZ31B-H24 and 0.8 mm thick galvanized mild steel, without and with adhesive, was conducted. Adhesive used was a one-component, heat-cured epoxy material, and was applied between overlapped sheets before USW. Corrosion test was conducted with an automotive cyclic corrosion test, which includes cyclic exposures of dipping in the 0.5% sodium chloride (NaCl) bath, a constant humidity environment, and a drying period. Lap shear strength of the joints decreased with the cycles of corrosion exposure. Good joint strengths were retained at the end of 30-cycle test.

Recreational marine engine operation effects water quality as well as air quality. Significant quantities of hydrocarbons are discharged into the rivers, lakes, and estuaries used as recreational boating waters. In order to investigate the impact of recreational marine engine operation on water quality, a MerCruiser 3.0LX four-cylinder four-stroke inboard engine and a Mercury 650 two-cylinder two-stroke outboard engine were tested using EPA required certification procedures. Both engines were tested with exhaust gas/cooling water mixing (scrubbing) in the exhaust stream using both freshwater and saltwater. Additionally, the inboard engine was tested without exhaust scrubbing. Gaseous emissions (HC, NOX, CO, and CO2) from the engines were continuously measured using a constant volume sampling system. Both exhaust gas and cooling water samples were collected and speciated for hydrocarbon species present.

A brief overview of the history and scope of the SAE Oil Labeling Assessment Program is presented. Then, the results of analyses on 893 samples of engine oil purchased in the retail market over the first three years of the program, are discussed. All samples were labeled with the API SF or SG Service Category, separately, or in combination with an API “C” category designation. Additionally, 43 engine oil samples found to be questionably labeled, were repurchased and analyzed; these results are included.

The project objective was to investigate the ultrafine solid particle emissions of the prevalent traffic, by performing field measurements at an urban traffic artery in Zurich/Switzerland. Subsequently, various scenarios were postulated to assess the potential of the diesel particle filters (DPF) to improve curbside air quality. Soot aerosols are known to be carcinogenic [1]. If all heavy-duty diesel vehicles were equipped with DPFs, then the number of particles emitted from the entire vehicle fleet could be reduced by 75 to 80%. For PM10, the curtailment scope is considerably lower, around 20%, because more than half of those emissions are not from the exhaust and therefore would not be filtered.

Edge cracking is one of the major formability concerns in advanced high strength steel (AHSS) stamping. Although finite element analysis (FEA) together with the Forming Limit Diagram has been widely used, it has not effectively predicted edge cracking. Primary problems in developing a methodology to insure that parts are safe from edge cracking are the lack of an effective failure criterion and a simple and accurate measurement method that is not only usable in both die tryout and production but also can be verified by finite element analysis. The intent of this study is to develop a methodology to ensure that parts with internal cutouts, such as a body side panel can be produced without edge cracking. During tryout and production, edge cracking has traditionally been detected by visual examination, but this approach is not adequate for ensuring freedom from edge cracking.

Adding oxygenates to diesel fuel has shown the potential for reducing particulate (PM) emissions in the exhaust. The objective of this study was to select the most promising oxygenate compounds as blending components in diesel fuel for advanced engine testing. A fuel matrix was designed to consider the effect of molecular structure and boiling point on the ability of oxygenates to reduce engine-out exhaust emissions from a modern diesel engine. Nine test fuels including a low-sulfur (∼1 ppm), low-aromatic hydrocracked base fuel and 8 oxygenate-base fuel blends were utilized. All oxygenated fuels were formulated to contain 7% wt. of oxygen. A DaimlerChrysler OM611 CIDI engine for light-duty vehicles was controlled with a SwRI Rapid Prototyping Electronic Control System. The base fuel was evaluated in four speed-load modes and oxygenated blends only in one mode. Each operating mode and fuel combination was run in triplicate.

The overall program objectives were three fold: assess the benefits and limitations of oxygenated diesel fuels on engine performance and emissions identify oxygenates most suitable for potential use in future diesel formulations based on physico-chemical properties (e.g. flash point), toxicity, biodegradability and estimated cost of production perform limited emissions and performance testing of the oxygenated diesel blends select at least two oxygenated compounds for advanced engine testing In Part 1 of this program which is described in this paper, an extensive literature review was conducted to identify potential oxygenates for blending into diesel fuels. As many as 71 oxygenates were identified for the initial screening process. Based on a set of physical and chemical properties, a screening methodology was developed to select the 8 oxygenates that will be eligible for engine testing.

Modern approaches to durability assurance in ground vehicle design are reviewed in the context of recent developments in computer-based analytical and experimental tools for use by designers and development engineers. Examples, using an automotive wheel assembly, are presented to illustrate the application of fatigue analysis in product development. Major challenges associated with the linking of various design tools into integrated networks appropriately configured for industrial problem solving are discussed along with an assessment of the potential benefits to be gained from such integration.

A review of many years of published work has shown that hydrogen embrittlement can occur under rolling contact conditions. Breakdown of lubrication and contamination with water have been cited as the probable sources of atomic hydrogen. In this paper, a unique fracture morphology is identified and the mechanism of the fracture progression from initiation to final catastrophic failure is proposed. Development of beneficial residual compressive stress near the contacting surfaces is one approach used to avoid this type of failure. Several alternative methods capable of developing a more desirable stress distribution will be discussed.

An oxidation catalyst was fitted on a DI diesel engine for an experimental study involving an oxidation catalyst and the use of superheated steam for fumigating the intake air. Results are compared with that of the influence of low level of fumigation of the intake air with superheated diesel fuel. Exhaust emissions of NOx, CO, UHC, TPM, SOF and Carbon were measured and quantified on upstream and downstream of a low light off temperature (250 °C) oxidation catalyst. The technique used an electric vaporizer for producing superheated steam and prevaporised superheated diesel fumes at 350 °C, respectively. A low emissions version of Perkins 4-236 engine with squish lip piston was run both with and without fumigation at two speeds 1200 rpm and 2200 rpm. Roughly covering both city and highway running conditions.

Results showed the influence of the oxidation catalyst on exhaust emissions from a DI diesel engine due to the partial premixing, fumigation of the intake air with diesel fuel. Exhaust emissions of NOx, CO, UHC, TPM, SOF and Carbon were measured and quantified on upstream and downstream of a low light off temperature (250 °C) oxidation catalyst. Two methods of diesel fumigation of the intake air with fuel were used. The difference between these two methods was the degree of premixing of diesel fuel with the intake air. The first technique used a high-pressure fine diesel spray onto a glow plug and the second technique used an electric vaporizer for prevaporised superheated diesel fumes at 350 °C. A low emissions version of Perkins 4-236 engine with squish lip piston was run both with and without fumigation at two speeds 1200 rpm and 2200 rpm. Roughly covering both city and highway running conditions.

Remote sensing nitric oxide (NO) measurements are difficult to analyze because load varies among on-road vehicles measured by remote sensing and NO emissions are dependent on load. Remote sensing NO measurements were made on passenger cars in 1997, 1998, and 1999 in Chicago, IL at a site where few vehicles had loads greater than those encountered in the FTP. Passenger car NO emissions could be modeled by an equation with an age term and a load term for measurements made under moderate load. Onset of decreasing NO emissions with increasing load was observed to occur at lower load for older technology vehicles. Light duty vehicles were measured by remote sensing at two sites on the same ramp in Phoenix, AZ. A large proportion of the vehicles at one of the sites was under loads far in excess of those experienced in the FTP. NO could not be characterized by a single valued function of age and load for both Phoenix sites even though the fleet at the two sites was very similar.

Both physical experiments and detailed chemical kinetics studies establish that Sonex micro-chambers imbedded in the walls of the piston bowl of an I.C. engine generate highly reactive intermediate chemical species and radicals- which, when allowed to mix with the fresh charge of the next cycle in the main chamber, substantially alter the chemical kinetics of main chamber combustion. A much more stable overall combustion process is observed, requiring substantially leaner air-fuel ratios than normal, and with much lower ignition temperatures. The net result, without any efficiency penalty, is an engine with an “ultra-clean” exhaust and with a greater tolerance to a wider range of fuels. Crucial to this process is the quenching of the flame in the passages connecting the micro-chambers to the piston bowl. It is flame quenching which enables the incomplete combustion of the charge trapped in the micro-chamber cavities.

This numerical study examines the chemical-kinetics mechanism responsible for EGR NOx reduction in standard engines. Also, it investigates the feasibility of using EGR alone in hydrogen-air and methanol-air combustion to help generate and retain the same radicals previously found to be responsible for the inducement of the autoignition (in such mixtures) in IC engines with the SONEX Combustion System (SCS) piston micro-chamber. The analysis is based on a detailed chemical kinetics mechanism (for each fuel) that includes NOx production. The mechanism for H-air-NOx combustion makes use of 19 species and 58 reactions while the methanol-air-NOx mechanism is based on the use of 49 species and 227 reactions. It was earlier postulated that the combination of thermal control and charge dilution provided by the EGR produces an alteration in the combustion mechanisms (for both the hydrogen and methanol cases) that lowers peak cycle temperatures-thus greatly reducing the production of NOx.

The Auto/Steel Partnership Corrosion Project Team has completed a perforation corrosion test program consisting of on-vehicle field exposures and various accelerated tests. Steel sheet products with eight combinations of metallic and organic coatings were tested, utilizing a simple crevice coupon design. On-vehicle exposures were conducted in St. John's and Detroit for up to seven years to establish a real-world performance standard. Identical test specimens were exposed to the various accelerated tests, and the results were compared to the real-world standard. This report documents the results of these tests, and compares the accelerated test results (including SAE J2334, GM9540P, Ford APGE, CCT-I, ASTM B117, South Florida Modified Volvo, and Kure Beach (25-meter) exposures) to the on-vehicle tests. The results are compared in terms of five criteria: extent of corrosion, rank order of material performance, degree of correlation, acceleration factor, and control of test environment.

The results of analyses on 300 samples of engine oil purchased in the retail market in 1990 are discussed. All samples were labeled with the API SF or SG Service Category, separately, or in combination with an API C category designation. Also, 17 oils previously found to be questionably labeled, from the 1989 set, were repurchased and analyzed. These results are included.