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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.

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.

Hydraulic fluids of the HFC category are aqueous polymer solutions with a fire resistance enhancing water content of 35 to approx. 50 %. The use of HFC fluids, above all in mobile and stationary drives in mining and in casting is subject to restrictions resulting from a number of features of a fluid. Field practice has shown that while axial-piston pumps may be successfully operated using HFC fluids, rolling bearing failures reduce their operational lifetimes. The bearing failures essentially result from material fatigue. This can be remedied by new quality steel for roller bearings. The combination of high fatigue life and corrosion resistance assures a wide application range for nitrogen-treated steel qualities.

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.

This paper presents an overview of the Driver Performance Data Book under preparation by the National Highway Traffic Safety Administration (NHTSA). It includes a brief discussion of the purpose of the Data Book, the restrictions placed on the development effort, and how it is expected that it will be used by Agency personnel and others. Sample pages from the document are reproduced to illustrate the basic format, and the Table of Contents of each section is presented to identify the major topics covered and indicate the number of pages devoted to each.

Die cast AZ91D and AM60 magnesium alloy components are finding increasing usage in automotive applications. Both hot and cold chamber die cast components of these alloys generally exhibit several common microstructural features, including “skin”, porosity banding, and porosity distributed about the component centerline. Methods for quantitatively characterizing these microstructural features are described and representative values for skin thicknesses, porosity band dimensions and porosity band locations from selected die castings will be presented. The expected influence of these common microstrucutral features on mechanical properties and acceptability of die cast magnesium components for given applications are discussed.

The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer test variability during performance testing. In addition, dynamometer test results have been compared and correlated to vehicle testing. Even though there is already a vast amount of anecdotal evidence confirming the fact that different procedures generate different friction coefficients on the same brake corner, the availability of supporting data to the industry has been elusive up to this point. To overcome this issue, this paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory friction evaluation tests.

In this paper, we propose an IC engine fuel system diagnostic algorithm based on a discrete-event nonlinear observer using the production oxygen sensor. A mean value engine model is used to describe the engine dynamics. A procedure for designing the discrete event based observer is presented and applied to estimate important engine variables using the measured binary oxygen sensor output. The estimated variables are then used to perform diagnostics of the fuel system of the IC engine. Experimental results on a multi-cylinder production engine are presented to demonstrate the effectiveness of the proposed method.

Current vehicle climate control systems are dramatically overpowered because they are designed to condition the cabin air mass in a specified period of time. A more effective and energy efficient objective is to directly achieve thermal comfort of the passengers. NREL is developing numerical and experimental tools to predict human thermal comfort in non-uniform transient thermal environments. These tools include a finite element model of human thermal physiology, a psychological model that predicts both local and global thermal comfort, and a high spatial resolution sweating thermal manikin for testing in actual vehicles.

The purpose of this paper is to survey the adverse environmental impacts resulting from motor vehicles, to review technologies developed to address these problems, and to summarize the current status of pollution control programs around the world.

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.

This paper provides a review of the fatigue properties reported in the open literature for die cast magnesium-based alloys. Recently developed fatigue data, in the form of stress versus number of cycles to failure for bending fatigue (R=-1), are presented for die cast AM60B and AZ91D alloy specimens with thicknesses between 1 and 10 mm. The effects of specimen thickness and macrostructural features, such as porosity distributions and surface features (parting line and ejection pin marks), on the fatigue data are discussed.

Many discrete tonal type noise and vibration problems in automotive systems and other physical structures require passive multi-layer visco-elastic damping treatments in mid to high frequency regimes. To address such issues, experimental modal analysis and dynamic finite element methods are suggested as suitable tools. Results are presented in terms of several test structures (four thin elastic beams, a thick elastic plate and an automotive brake pad) with free-free boundary conditions. Composite modal loss factors are measured and predicted for two different damping insulators consisting of adhesive, steel and coating combinations. Special attention is paid to the elastic deformation modes of test structures and spectral scaling of material properties for the finite element models.

The motivation of this paper is inverse estimation of the material properties for sheet metals subjected to cyclic loading. Cyclic three-point bending tests are performed. Bending moments are computed from the measured data, namely, punch stroke, punch load, bending strain and bending angle. Bending moments are also calculated based on the selected material model in which normal anisotropy and combined hardening are considered. Material parameters are identified by minimizing the difference between these two bending moments. Modified Levenberg-Marquardt method is used in the optimization procedure. Stress-strain curves are generated with the optimized material parameters.

In sheet metal forming, drawbeads are often used to control uneven material flow which may cause defects such as wrinkles, fractures, surface distortion and springback. Appropriate setting and adjusting the drawbead force is one of the most important parameters in sheet forming process control. However, drawbead design and drawbead force adjustment still rely on trial-and-error procedures. This paper summarizes the guidelines in drawbead design, evaluates a number of mathematical models in estimating drawbead forces, and investigates the effects of sheet thickness, material properties, drawbead geometry and penetration on the drawbead force.

Reported tensile and fatigue properties of die cast AZ91D and AM60B magnesium alloys indicate that those values depend on the size and shape of the test samples and their global porosities. This paper reviews the mechanical properties reported in the open literature for these die cast alloys and indicates that section thickness and global porosity are inadequate for predicting the tensile and fatigue properties of die cast AZ91D and AM60B magnesium alloys.

The aerodynamics of the STOL aircraft can experience significant changes in proximity to the ground. A review of the existing data base and methodologies has been made and the results of that review are presented in this paper. The existing data show that in ground proximity the STOL aircraft will generally experience a reduction in the lift component regardless of the lifting configuration. Those configurations with integrated power and lift systems will have an additional effect of ground induced aerodynamic changes. This paper will discuss the existing data base and the deficiencies of that data base.

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.

There is an ongoing interest in biodegradable hydraulic fluids. Biodegradable fluids are often considered to include only vegetable oils, polyol esters and diester base stocks. However, other fluid base stocks including highly refined mineral oils, poly(alpha olefins) and fire-resistant fluids such as water-glycol hydraulic fluids are also biodegradable fluid alternatives. This paper will provide an overview of the international literature on biodegradable fluids, various international testing protocol, fluid base stocks, effect of oxidative stability, material compatibility and pump performance.

A newly developed process allows the near-net shape fabrication of alumina/aluminum composite bodies via the immersion of a sacrificial oxide preform into a molten aluminum alloy bath. The resulting composite possesses an attractive range of properties for application in several automotive components. These properties include: high strength and stiffness, appreciable thermal and electrical conductivity, high strength at elevated temperatures, coefficient of thermal expansion of 10 X 10-6 C-1 and relative ease of machinability. Low cost fabrication renders this material/process ideal for components such as brake rotors and calipers, cylinder bore liners, piston components.