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Experimental procedures and results of a benchmark test for springback are reported and a complete suite of obtained data is provided for the validation of forming and springback simulation software. The test is usually referred as the Slit-Ring test where a cylindrical cup is first formed by deep drawing and then a ring is cut from the mid-section of the cup. The opening of the ring upon slitting releases the residual stresses in the formed cup and provides a valuable set of easy-to-measure, easy-to-characterize springback data. The test represents a realistic deep draw stamping operation with stretching and bending deformation, and is highly repeatable in a laboratory environment. In this study, six different automotive materials are evaluated.

Not only well-functioning, but also the way operating everyday items "feel", gauges costumer perception of an automobile robustness. To prevent costumer dissatisfaction with door trim panel movement when operating power windows, deflections must be kept small. Deflections of inner panel are seen through trim panel and are responsible for giving a flimsy idea of the door. In this paper, inner panel movement for a fully stamped door in full glass stall up position is analyzed. Through CAE analyses, inner panel behavior was compared, considering different types of reinforcement for belt region.

The oil distribution system of an automotive light duty engine typically has an oil pump mechanically driven through the front-endancillaries-drive or directly off the crankshaft. Delivery pressure is regulated by a relief valve to provide an oil gallery pressure of typically 3 to 4 bar absolute at fully-warm engine running conditions. Electrification of the oil pump drive is one way to decouple pump delivery from engine speed, but this does not alter the flow distribution between parts of the engine requiring lubrication. Here, the behaviour and benefits of a system with an electrically driven, fixed displacement pump and a distributor providing control over flow to crankshaft main bearings and big end bearings is examined. The aim has been to demonstrate that by controlling flow to these bearings, without changing flow to other parts of the engine, significant reductions in engine friction can be achieved.

The forming effects along with strain rate, actual material properties and weld effects have been found to be very critical for accurate prediction of crash responses especially the prediction of local deformation. As a result, crash safety engineers started to consider these factors in crash models to improve the accuracy of CAE prediction and reduce prototype testing. The techniques needed to incorporate forming simulation results, including thickness change, residual stresses and strains, in crash models have been studied extensively and are well known in automotive CAE community. However, a challenge constantly faced by crash safety engineers is the availability of forming simulation results, which are usually supplied by groups conducting forming simulations. The forming simulation results can be obtained by either using incremental codes with actual stamping processes or one-step codes with final product information as a simplified approach.

We describe an optimization model developed by Ford Motor Company to reallocate stamped parts between facilities when business conditions change. How can the business meet new targets when demand starts to exceed existing capacity? Likewise, how can it respond when demand is lower than expected? Sometimes the business can reduce costs by transferring production to a different location or by outsourcing parts. We describe in this paper how mathematical optimization can identify solutions that balance both logistical and outsourcing costs. We explain the algorithm and demonstrate with a small example how it recommends sourcing plans that minimize cost.

In recent years, the slip lock-up mechanism has been adopted widely, because of its fuel efficiency and its ability to improve NVH. This necessitates that the automatic transmission fluid (ATF) used in automatic transmissions with slip lock-up clutches requires anti-shudder performance characteristics. The test methods used to evaluate the anti-shudder performance of an ATF can be classified roughly into two types. One is specified to measure whether a μ-V slope of the ATF is positive or negative, the other is the evaluation of the shudder occurrence in the practical vehicle. The former are μ-V property tests from MERCON® V, ATF+4®, and JASO M349-98, the latter is the vehicle test from DEXRON®-III. Additionally, in the evaluation of the μ-V property, there are two tests using the modified SAE No.2 friction machine and the modified low velocity friction apparatus (LVFA).

Oil formulation has been varied to modify oil viscosity characteristics; the effect on the rubbing friction losses of a 2.4litre diesel engine has been investigated for a range of temperatures from -20 to around 60°C. The aims of the study were first, to examine the extent to which viscosity alone determined the effect of formulation changes, and second, to define an effective viscosity to relate changes in viscosity due to formulation and temperature to changes in engine friction. This effective viscosity is based on cold cranking simulator measurements at -30°C, high temperature high shear viscosity at 150°C and kinematic viscosity measurements at three intermediate temperatures to define the variation with temperature. The effective viscosity has been described using a modified Vogel equation, which is presented.

Usually in Computer Aided Engineering (CAE) analyses, Computer Aided Design (CAD) data is meshed and analyzed with regard to displacements and stresses. So far, it is not common to account for residual stresses due to the manufacturing process in these analyses. This work proposes a methodology based on simplified abaqus Standard/Explicit models to evaluate residual stresses due to stamping and bending manufacturing process in truck rails and suggests a methodology to use this residual stress data in truck frame CAE durability analysis making it possible to compare how different a predicted fatigue life can be when residual stresses are considered.

The risk of skid lines for Class A panels has to be assessed before releasing the die development for hard tooling. Criteria are needed to predict skid lines in the formability evaluation stage to avoid expensive changes to tooling and process for resolving skid line issue in production. In this study, criteria using three different measured parameters were developed and validated. A draw-stretch-draw (DSD) test procedure was developed to generate skid lines on lab samples for the physical evaluation. This was done using tooling with various die entry radii and different draw beads. The skid line severity of lab samples was rated by specialists in the inspection of automotive outer panel surface quality. The skid line rating was correlated with geometric measurements of the lab samples after the DSD test. The sensitivity of the appearance of skid lines to tooling and process parameter variations was identified.

In order to detect degradation of engine oil lubricant, bench testing along with a number of diesel-powered Ford trucks were instruments and tested. The purpose of the bench testing was primarily to determine performance aspects such as repeatability, hysteresis effects and so on. Vehicle testing was conducted by designing and installing a separate oil reservoir along with a circulation system which was mounted in the vicinity of the oil pan. An innovative oil sensor was directly installed on the reservoir which can measure five (5) independent oil parameters (viscosity, density, permittivity, conductance, temperature). In addition, the concept is capable of detecting the oil level continuously during normal engine operation. The sensing system consists of an ultrasonic transducer for the oil level detection as well as a Tuning Fork mechanical resonator for the oil condition measurement.

Forming Limit Diagrams (FLD) have been widely and successfully used in sheet metal stamping as a failure criterion to detect localized necking, which is the most common failure mechanism for conventional steels during forming. However, recent experience from stamping Dual-Phase steels found that, under certain circumstances such as stretching-bend over a small die radius, the sheet metal fails earlier than that predicted by the FLD based on the initiation of a localized neck. It appears that a different failure mechanism and mode are in effect, commonly referred to as “shear fracture” in the sheet metal stamping community. In this paper, experimental and numerical analysis is used to investigate the shear fracture mechanism. Numerical models are established for a stretch-bend test on DP780 steel with a wide range of bend radii for various failure modes. The occurrences of shear fracture are identified by correlating numerical simulation results with test data.

Die wear is a significant issue in sheet metal forming particularly for stamping Advanced High-Strength Steels (AHSS) because of their higher strength and microstructure composition. Reliable predictions of the magnitude and distribution of die wear are essential if cost-effective wear-protection strategies are desired in the early stages of tooling development. A die Wear Severity Index (WSI) is introduced in this paper to quantify the magnitude of die wear, which in essence characterizes the frictional energy dissipation per unit area on the die surface throughout the entire forming cycle. It can be readily obtained as part of any finite element simulation of stamping process utilizing incremental solution techniques.

High concentrations of diesel fuel can accumulate in the engine oil, especially in vehicles equipped with diesel particle filters. Fuel dilution can decrease the viscosity of engine oil, reducing its film thickness. Higher concentrations of fuel are believed to accumulate in oil with biodiesel than with diesel fuel because biodiesel has a higher boiling temperature range, allowing it to persist in the sump. Numerous countries are taking actions to promote the use of biodiesel. The growing interest for biodiesel has been driven by a desire for energy independence (domestically produced), the increasing cost of petroleum-derived fuels, and an interest in reducing greenhouse gas emissions. Biodiesel can affect engine lubrication (through fuel dilution), as its physical and chemical properties are significantly different from those of petrodiesel. Many risks associated with excessive biodiesel dilution have been identified, yet its actual impact has not been well quantified.

The recirculation of gases from the crankcase and valvetrain can potentially lead to the entrainment of lubricant in the form of aerosols or mists. As boost pressures increase, the blow-by flow through both the crankcase and the valve cover increases. The resulting lubricant can then become part of the intake charge, potentially leading to fouling of intake components such as the intercooler and the turbocharger. The entrained aerosol which can contain the lubricant and soot may or may not have the same composition as the bulk lubricant. The complex aerodynamic processes that lead to entrainment can strip out heavy components or volatilize light components. Similarly, the physical size and numbers of aerosol particles can be dependent upon the lubricant formulation and engine speed and load. For instance, high rpm and load may increase not only the flow of gases but the amount of lubricant aerosol.

The effects of lubricant on lap shear strength of Spot Friction Welded (SFW) joints made of 6111-T4 alloys were studied. Taguchi L8 design of experiment methodology was used to determine the lubricant effects. The results showed that the lap shear strength increased by 9.9% when the lubricant was present at the top surface compared to that of the baseline (no lubricant) whereas the lap shear strength reduced by 10.2% and 10.9% when the lubricant was present in the middle and at the bottom surfaces compared to that of the baseline (no lubricant), respectively. The microstructure analysis showed a zigzag interface at the joint between the upper and the lower sheet metal for the baseline specimen, the specimens with the lubricant at the top and at the bottom. However, a straight line interface is exhibited at the joint between the upper and the lower sheet for the specimen with the lubricant in the middle. The weld nugget sizes of the lap shear tested specimens were measured.

The application of polyalkylene glycol (PAG) as a base stock for engine oil formulation has been explored for substantial fuel economy gain over traditional formulations with mineral oils. Various PAG chemistries were explored depending on feed stock material used for manufacturing. All formulations except one have the same additive package. The friction performance of these oils was evaluated in a motored single cylinder engine with current production engine hardware in the temperature range 40°C-120°C and in the speed range of 500 RPM-2500 RPM. PAG formulations showed up to 50% friction reduction over GF-5 SAE 5W-20 oil depending on temperature, speed, and oil chemistry. Friction evaluation in a motored I-4 engine showed up to 11% friction reduction in the temperature range 40°C-100°C over GF-5 oil. The paper will share results on ASTM Sequence VID fuel economy, Sequence IVA wear, and Sequence VG sludge and varnish tests. Chassis roll fuel economy data will also be shared.

This paper describes the basic principles of extensional rheometry, and the successful application to a variety of automotive fluids, including gear lubricants, paints, and forming lubricants. These fluids are used under very complex flow fields containing strong extensional (elongational) components. While exact derivation of extensional viscosities involves sophisticated theories, the measurement of liquid filament break-up time can provide fruitful information. Gear lubes showed different break-up time according to the kinematic viscosities. Addition of viscosity modifier (acrylic copolymer) significantly increased the breakup time, whereas surfactants had little effect. Clearcoat paint sample increased the breakup time, perhaps due to the deterioration. The waxy stamping lubricant showed remarkable change in the extensional properties as the temperature is raised.

During the assembly process of planetary gears, the pinion shaft is initially pressed in to the planetary carrier and then staking is performed to fix the pinion shaft to the carrier. The main purpose of the staking process is to prevent the movement of the pinion shaft during transmission operation. During assembly there should be minimal distortion of the assembly. The press-in process, pinion shaft and carrier are subjected to extremely high frictional loading due to the interference fit. The staking process permanently deforms the pinion shaft top and bottom ends, forming a protrusion that holds the shaft in position. The pinion shaft needs to sustain operational loads exerted by helical planetary gears, which tend to push the carrier flange out of position during operation. Staking length, staking force and interference between shaft and carrier hole are the critical parameters, which determine the maximum axial force that the pinion shaft can withstand.

In an effort to improve fuel economy for light duty trucks, an initiative was undertaken to reduce frictional losses in rear axle through use of low friction lubricants and novel surface finish on gears while maintaining durability. This paper describes the effect of rear axle lubricants on fuel economy. A laboratory rig was set up using a full size pick-up truck rear axle to measure axle efficiency and lubricant temperature with various SAE 75W-90 and SAE 75W-140 viscosity grade lubricants. Traction coefficients of lubricants were also measured at various temperatures using a laboratory ball and disk contact geometry. An improvement in axle efficiency up to 4.3% was observed over current Ford factory fill SAE 75W-140 lubricant depending on speed, torque and the type of lubricant used. The temperature of the lubricants was also lower than that with the current factory fill. This is important for maintaining bearing life and overall durability of the rear axle.

Automotive manufacturers around the world are pushing towards the goal of better safety from their vehicles without compromising on the fuel economy. One of the very successful efforts in this direction is the hot forming technique that has been around for 30 years since Saab used it for the first time in 1986. Finite element simulations for this technique are of paramount importance to identify and optimize the process; as the steels used in hot stamping are sensitive to certain variables when heated that would otherwise cause very few disturbances in a normal cold forming process. The major contributor to the high strength of the stamped part is the phase transformation that it undergoes during the hot forming process. This paper investigates and identifies critical parameters through Finite Element Analysis (FEA) simulations.