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One of the more useful metrics to characterize the high frequency performance of an isolator is insertion loss. Insertion loss is defined as the difference in transmitted vibration in decibels between the non-isolated and isolated cases. Insertion loss takes into account the compliance on the source and receiver sides. Accordingly, it has some advantages over transmissibility especially at higher frequencies. In the current work, the transfer matrix of a spring isolator is determined using finite element simulation. A static analysis is performed first to preload the isolator so that stress stiffening is accounted for. This is followed by modal and forced response analyses to identify the transfer matrix of the isolator. In this paper, the insertion loss of spring isolators is examined as a function of several geometric parameters including the spring diameter, wire diameter, and number of active coils.

Many tire construction parameters influence rolling resistance and cornering force properties. This paper concentrates on the influence of the stabilizer ply geometry of radial passenger car tires. Using a designed experiment, the construction parameters studied were: the width of the stabilizer plies relative to the tread arc width, the crown angle of the stabilizer plies and the amount of rubber gauge above and below the stabilizer ply edges. Results indicate a strong relationship exists between these construction parameters and rolling resistance and cornering force properties.

External components of an automotive body are manufactured from a stamping of sheet metal plane resulting in a final product with variable thickness due to different levels of stretch and a heterogeneous distribution of residual plastic strain. Generally, these informations are not considered in numerical simulations of the product and may cause considerable errors in the analysis of stamped parts involving nonlinearities. This work aimed to simulate an event called palm-printing in an automobile fender, with and without the consideration of the final data of the numerical simulation of the stamping process (final thickness and residual plastic strain) and the results compared with those obtained experimentally. Results showed that the consideration of thickness and hardening from the stamping process can improve the correlation of final results in quasi-static nonlinear analysis.

A new set of standard conditions for the road coastdown procedure was established from the literature. The change in road load predicted from the road and dynamometer coastdown procedures was evaluated using this new set of conditions and the current set of conditions for a twenty four vehicle sample. These changes in road load were related to changes in fuel economy using relationships published by the Environmental Protection Agency. No significant change in fuel economy was predicted when using the new conditions. A sensitivity analysis was performed on the new set of conditions with respect to road load.

Numerous studies have validated EDSMAC4 as an effective method of reconstructing automobile collisions; however, little has been done to investigate the effect of varying stiffness coefficients on the results of accident reconstruction and simulation analyses. When comparing simulations to staged collisions, the stiffness coefficients are frequently well defined; however, this is not always the case in real world accidents. Six vehicle-to-vehicle test impacts were modeled using EDSMAC4. Stiffness coefficients for the vehicles were obtained from test data of exemplar vehicles. After modeling the impacts with the base stiffness level, the stiffness coefficients were modified for both vehicles either plus (+) or minus (−) 25%. The impacts were re-run and the predicted vehicle damage (maximum crush and pattern), impact severity (Delta-V), peak acceleration, impact duration, post impact trajectory, and impact force was compared.

A number of emerging automotive applications of die cast Mg-Al alloys involve components such as seats, steering wheels and instrument panel supports. These components may be subjected to strain rates as high as 200 s-1 during an automobile collision. Deformation and fracture behavior during high rates of loading are, therefore, of considerable interest. However, little work has been done to measure the effect of elevated strain rates or temperature on the energy absorption properties of the Mg-Al alloys. Thus, in an effort to provide additional information, the present work reports that the mean yield strength and strain hardening rates for die cast AM60B appear to be a strong function of strain rate from 10-3 s-1 to 103 s-1 and temperature from -196 to 25 °C. Both the total energy absorption and total deflection of AM60B Charpy impact bars increased with increasing temperature in the range from -196 to 300 °C.

High strain rate sheet tensile tests (up to 300s-1) and Ohio State University (OSU) formability tests (up to an estimated strain rate of 10s-1) were performed to examine the effect of strain rate on the mechanical properties and formability of five ferritic stainless steels: HIGH PERFORMANCE-10™ 409 (HP-10 409), ULTRA FORM® 409 (UF 409), HIGH PERFORMANCE-10™ 439 (HP-10 439), two thicknesses of 18 Cr-Cb™ stainless steel, all supplied by AK Steel, and Duracorr®, a ferrite-tempered martensite dual-phase stainless steel supplied by Bethlehem Steel Corporation. Tensile results show that increasing strain rate resulted in increases in yield stress, flow stress, and stress at instability for all alloys tested. In addition, increases in uniform and total elongation were also found for each of the five alloys.

The bright surface finish of exterior automotive moldings made from stainless steel can become hazed and reflections distorted as a result of forming done during the manufacturing processes. Bright moldings are frequently used to give styling differentiation accents to vehicle exteriors. Stainless steel provides cost effective differentiation with a material that is durable and relatively easy to form to shapes desired by the stylist. Because of the desirable attributes of stainless steel, an understanding of the threshold of unacceptable surface appearance is necessary to maximize showroom appeal and avoid customer complaints that result in warranty claims. This paper quantifies the effect that manufacturing strain and strain rate have on the surface finish of 436M2 stainless steel. Controlled experiments were conducted on production grade stainless steel strips subjected to a variety of strain and strain rates typical of manufacturing processes.

Erosion damage to automotive car bodies caused by stones and small sand particles and road debris significantly affects the appearance of paint. Painted engineering plastics as well as precoated sheet steel are affected by erosion phenomenon. Erosion of painted plastic substrates results in cosmetic concerns while that on metal substrates results in cosmetic to perforation corrosion. This work describes a laboratory simulation of erosion of painted plastic substrates by small particles on various paint and substrate types. Gloss loss was used to quantitatively evaluate erosion of painted surfaces. Wear behavior of painted plastic substrates to slag sand impact was evaluated as a function of several variables including paint type (one-component melamine crosslinked (1K) vs. two-component isocyanate crosslinked (2K)), thermal history, and coating modulus. The effect of slag sand type (particle size and chemical composition) was studied.

This paper reviews research done by the Systems Research Group at The Ohio State University on the information-seeking behavior of automobile drivers. The effect of sleep deprivation, long-term driving, and low levels of alcohol intoxication on driver eye-movement patterns is discussed. The adaptive behavior which results from loss of peripheral information processing capability under stress is manifested through wider dispersion and less preview by the tired drivers and tunnel vision by the intoxicated drivers. The loss of this information can be expected to result in unsafe performance.

The internal stress of electroless nickel (EN) deposits is shown to be the sum of two components, intrinsic and thermal. A method of measuring the stress components is discussed. The stress is shown to be dependent on the chemistry of the plating bath as well as the phosphorus content of the EN deposit. The corrosion behavior of EN deposits is shown to be dependent on stress and the near-surface phosphorus content. The effect of EN deposits on fatigue strength of steel is also discussed.

This study relates the structural stiffness and kinetic energy of impact to the dynamic response of a belted vehicle occupant. Acceleration time histories of impact for structures with different stiffnesses were obtained by performing a finite element analysis using the LS-DYNA3D finite element program and a model representing a structural member made of AISI 4340 steel. For the human body dynamics analysis, the Articulated Total Body (ATB) computer program was used to perform six simulations of a 50 percentile male restrained by a 3-point seatbelt system for a co-linear -Gx impact.

On a 1.5L TGDI gasoline engine bench(without GPF), 4 lubricant oils A/B/C/D with different sulfated ash content (1.1wt.%/0.8wt.%/0.7wt.%/0.5wt.%) were used to test the impact on the emission of PN and PM under WLTC condition. In the test results, the PN and PM values of Oil A are the largest, 7.12E+12 p/km and 2.60mg/km respectively, the PN and PM values of Oil B and C are the equivalent, 5.58E+12 p/km&5.72E+12 p/km,1.81 mg/km & 2.03 mg/km respectively, and the PN and PM values of Oil D are 5.38E+12 p/km and 1.65mg/km respectively. The test results indicate that the sulfated ash content of engine oil affects the particulate emission level of the engine. Oil with high sulfated ash content(1.1 wt.%) has high emission values(PN&PM); Oils with low sulfated ash content (0.8wt.%) have lower emission values (PN&PM). When the sulfated ash content of the oil is below 0.8wt.%, there is almost no significant difference in emission values (PN&PM).

Following concern about the association between adverse health effects and ambient particulate concentrations, there are now an increasing number of heavy-duty Diesel engines fitted with catalysed particulate filters. These filters virtually eliminate carbon particle emissions but there is some evidence suggesting a potential to form a cloud of secondary nucleation particles post trap. This event occurs at high temperature operating conditions and is produced mainly from the increased sulphate production over the catalyst. This paper investigates the measurement of particle emissions from a heavy-duty engine operating over the European legislated cycle, both with and without a filter fitted and investigates how emissions are affected by the use of a sulphur-free Diesel fuel. The work also demonstrates a contribution to the measured nucleation particles from material desorbed not only from the trap, but also from the exhaust system.

The surface condition of sheet steel has been noted in the past to affect the occurrence of interfacial nugget failures of spot welds during qualification testing. A microalloyed 60 ksi minimum yield strength cold-rolled steel was observed to have an unusually high incidence of interfacial nugget tears when welded in the as-received condition, but virtually no interfacial tears when wiped before welding. Samples of welds from both the as-received and wiped materials were examined to determine the surface characteristic causing the interfacial failures. Using Auger surface analysis techniques, the presence of a high concentration of carbon relative to iron was observed on the surface. This carbonacious surface was found to be detrimental to the formation of successful spot welds.

Aluminum sheet is commercially available in three surface finishes, mill finish (MF), electric discharge texture (EDT), and dull finish (DF). This surface finish impacts the friction behavior during sheet metal forming. A study was done to compare ten commercially available sheet samples from several suppliers. The friction behavior was characterized in the longitudinal and transverse directions using a Draw Bead Simulator (DBS) test, resulting in a coefficient of friction (COF) value for each material. Characterization of the friction behavior in each direction provides useful data for formability analysis. To quantitatively characterize the surface finish, three-dimensional MicroTexture measurements were done with a WYKO NT8000 instrument. In general, the MF samples have the smoothest surface, with Sa values of 0.20-0.30 μm and the lowest COF values. The EDT samples have the roughest surface, with Sa values of 0.60-1.00 μm, and the highest COF values.

Experience in stamping plants has suggested that there are considerable differences in the ability of different chromium-plated dies to form sheet metal. Earlier laboratory work indicated that differences in friction resulting from different surface finishes among chromium-plated dies might be an important factor in the observed behavior. The effect of surface roughness was studied by measuring the friction of sheet metal drawn through chromium-plated drawbeads in a drawbead simulator. Surface roughness was varied by polishing the as-plated surface to smoother finishes, step-by-step, and measuring the friction at each step. It was found that rough finishes exhibited the highest friction. As the finish became smoother, friction was reduced. However, friction reached a minimum and began to rise as the finish became still finer. This suggests that in production tools there is an optimum surface roughness which will give the best forming for sheet metal stamping.

In this work hemp fibers were chemically treated in order to improve the fiber/matrix interaction in hemp fiber/unsaturated polyester composites prepared by a Resin Transfer Molding (RTM) process. Chemicals used for paper sizing (AKD, ASA, Rosin Acid and SMA) as well as a silane compound and sodium hydroxide were used to modify the fibers' surface. The tensile, flexural and impact properties of the resulting materials were measured. A slight improvement in mechanical properties was observed for the SMA, silane and alkali treated specimens. However close analysis of these tests and of the fracture surface of the samples showed that there was no amelioration of the fiber/matrix adhesion. It was found that predicted tensile strengths using the rule of mixture were very close to the experimental values obtained in this work. Finally the properties of an hybrid glass fiber/hemp fiber composite were found to be very promising

A monolithic type aluminum (Al) cylinder made of hypereutectic Aluminum-Silicon alloy has been widely used for motorcycle applications. It has a lightweight structure and a superior cooling ability owing to its material property and surface finishing. Usually the cylinder bore surface of the monolithic type Al cylinder is finished by an etching process or a honing process in order to expose silicon (Si) particles from aluminum (Al) matrix for the improvement of the tribological properties. The morphology of the cylinder bore surface including the exposure of Si particles is supposed to make an important effect on its tribological properties, especially on the anti-scuffing property. In this research, the anti-scuffing property of three kinds of cylinder bore finishing, an etched surface, a Si exposure honed surface and a conventional plateau honed surface is evaluated with using a reciprocated type wear tester. The experimental results are analyzed by using Weibull analysis.

As a new vehicle is based on common vehicle platform, the durability problems of chassis components in development stage are decreasing. However a vehicle body structure is changed by exterior design and a chassis and a suspension are tuned by vehicle performance targets. The main issue on developing a new vehicle is to satisfy the durability target of a body structure and tuned suspension components. The accuracy of durability Computer Aided Engineering analysis is mainly depending on the accuracy of input loads and boundary conditions on suspension system. The input loads should be estimated accurately. These could be changed by vehicle specifications such as vehicle weight, wheel base and so on. It is also affected by the change of suspension types and tuning parameters. This paper presents the experimental parametric study results using road load data analysis techniques.