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(Paint) film as an alternative to spray applied paint has received growing attention in recent years. The potential for economic and environmental advantage and quality enhancement with this technology has been reported in several technical papers (Ref. 1, 3 and 4). The actual practice of film finishing, however, has received only limited notice. Film finishes have been applied to aluminum, stainless steel, PVC, and ABS. Starting in 1982, part applications include: wheel covers, door edge guards, window surrounds, roof drip moldings, lower windshield moldings, rocker panels, body side moldings, B pillars, and A pillars. Industry awareness and acceptance of film finishing as a viable alternative to spray applied paint is increasing. The two technologies are similar in many ways, yet distinctly different in other ways. They share a common goal: To yield a durable finish, economically and with superior visual impact. This paper reviews the unique aspects of film finishing.

To reduce the Body in White (BIW) mass, it is necessary to expand the application of Advanced High-Strength Steels (AHSS) to complex shaped parts. In order to apply AHSS to complex shaped parts with thinner gauge, high formability steel is required. However, higher strength steels tend to display lower elongations, compared with low/medium strength steels. Current AHSS are applied to limited parts for this reason. The new 1.2GPa material, with high formability, was developed to solve this issue. The mechanical property targets for the high elongation 1.2GPa material were achieved by precise metallurgical optimization. Many material aspects were studied, such as formability, weldabilty, impact strength, and delayed fracture. As the result of this development, 1.2GPa AHSS has been applied to a new vehicle launched in 2013.The application of this material was the 1st in the world, and achieved a 11kg mass reduction.

The demand for improved fuel economy in both cars and trucks has emphasized the need for lighter weight components. The application of high strength steel to wheels, both rim and disc, represents a significant opportunity for the automotive industry. This paper discusses the Ranger HSLA wheel program that achieved a 9.7 lbs. per vehicle weight savings relative to a plain carbon steel wheel of the same design. It describes the Ranger wheel specifications, the material selection, the metallurgical considerations of applying HSLA to wheels, and HSLA arc and flash butt welding. The Ranger wheel design and the development of the manufacturing process is discussed, including design modifications to accommodate the lighter gage. The results demonstrate that wheels can be successfully manufactured from low sulfur 60XK HSLA steel in a conventional high volume process (stamped disc and rolled rim) to meet all wheel performance requirements and achieve a significant weight reduction.

This paper describes the Electronic Air Suspension (EAS) System developed by Ford Motor Company. Design trade-offs between load-carrying capacity necessary with conventional steel spring suspension systems and riding comfort are avoided when today's microcomputer technology is combined with a leveling air spring suspension. An electric air compressor with regenerative air dryer, three electronic “Hall Effect” height sensors, four air springs with integral solenoids, and a control module with a single chip microcomputer are the key EAS System components discussed.

A theoretical model is presented for predicting springback of wide sheet metal subjected to 2D-stretch-bending operation. The material is assumed to be normal anisotropic with n-th power hardening law, σ = Fεn. Two types of stretch-bending experiment, bending with simultaneous stretching and stretch-bending followed by consecutive re-stretching, is conducted using AK sheet steel and sheet aluminum alloy A5182-O. The measured values of springback are in good agreement with analytical ones for a wide range of bending radii, stretching forces, and loading conditions. Furthermore, a calculation method for predicting springback configurations of 2D sheet metal parts with arbitrary cross-sections which include both stretch-bending and stretch-bending-unbending deformation is proposed.

Structure enhancement based on data monitored in a traditional side impact evaluation is primarily a trial and error exercise resulting in a large number of computer runs. This is because how the structure gets loaded and the degree of contribution of local structural components to resist the impact while absorbing energy during a side collision is not completely known. Developing real time complete load profiles on a body side during the time span of an impact is not an easy task and these loads cannot be calculated from that calculated at the barrier mounting plate. This paper highlights the load distribution, calculated by a procedure using computer aided engineering (CAE) tools, on a typical 2-door vehicle body side when struck by moving deformable barriers used in the insurance institute for highway safety (IIHS), EuroNCAP and LINCAP side impact evaluations.

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.

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.

This paper describes the engineering, manufacturing and integration necessary to produce the Corvette's first ever all-aluminum spaceframe (see Figure 1). The engineering and manufacturing of the spaceframe was a joint venture between General Motors and suppliers ALCOA (Aluminum Company of America) and Dana Corporation. ALCOA led the initial design of the spaceframe; Dana Corp led the manufacturing; General Motors' Engineering and Manufacturing groups led the integration of the assembly. The aluminum spaceframe design is modeled after the baseline steel structure of the Corvette coupe. The aluminum spaceframe reduces 140 lbs from the steel baseline and enters the plant at 285 lbs. This frame allows the 2006 Corvette Z06 to enter the market at a 3100 lbs curb weight. Aluminum casting, extruding, stamping, hydroforming, laser welding, Metal Inert Gas (MIG) welding, Self Pierce Riveting (SPR), and full spaceframe machining make up the main technologies used to produce this spaceframe.

Aircraft potable (drinking) water systems haven’t changed significantly in the last half-century. These systems consist of cylindrical water tanks pressurized by bleed air from the jet engines, with insulated stainless steel distribution lines. What has changed recently is the increase in the possibility of aircraft picking up contaminated drinking water at foreign and domestic stops. Customer awareness of these problems has also changed - to the point where having reliable drinking water is now a competitive issue among airlines. Old style potable water systems that are used on modern aircraft are high maintenance and exacerbate the growth of microbes because the water is static much of the time. The integrity of some pressurized water tanks are also a concern after years of use. Cost-effective mechanical and biological solutions exist that can significantly reduce the amount of chemicals added and provide good potable water.

The dynamics of vehicle front end crash are studied using the ADAMS dynamic simulation code. The analysis is carried out in three dimensions and can capture the behavior associated with an asymmetrical structure or impact mode. Subroutines which allow the modeling of structural crush and plastic hinge formation, contact forces and friction forces are discussed. The method is relatively inexpensive, but does require a good understanding of the problem on the part of the analyst. A discussion of the techniques that are used to model the structural system is given. The results of the analysis are compared with experimental data and the correlation is very encouraging.

A 3-D video sensor designed for in-vehicle operation is presented in this paper. This sensor enables improved occupant protection according to the Federal Motor Vehicle Safety Standard (FMVSS) 208 and beyond. Interior sensors integrated in current occupant protection systems are especially designed for Occupant Classification (OC). However, these interior sensors do not measure the distance between the head and the air bag module. As a result, the air bags deploy independently from the occupants' Out-Of-Position (OOP) status in crash situations. On the contrary, the sensor presented in this paper overcomes this shortcoming by providing dynamic Out-Of-Position Sensing (OOPS) capabilities in addition to occupant classification. The requirements of dynamic OOPS are discussed and an appropriate test device and test procedure are described. Furthermore, the paper presents the sensor principle, the hardware architecture and algorithms for image data processing.

Sudden tire deflation, or blow-out, is sometimes cited as the cause of a crash. Safety researchers have previously attempted to study the loss of vehicle control resulting from a blow-out with some success using computer simulation. However, the simplified models used in these studies did little to expose the true transient nature of the handling problem created by a blown tire. New developments in vehicle simulation technology have made possible the detailed analysis of transient vehicle behavior during and after a blow-out. This paper presents the results of an experimental blow-out study with a comparison to computer simulations. In the experiments, a vehicle was driven under steady state conditions and a blow-out was induced at the right rear tire. Various driver steering and braking inputs were attempted, and the vehicle response was recorded. These events were then simulated using EDVSM. A comparison between experimental and simulated results is presented.

According to accident analysis, submarining is responsible for most of the frontal car crash AIS 3+ abdominal injuries sustained by restrained occupants. Submarining is characterized by an initial position of the lap belt on the iliac spine. During the crash, the pelvis slips under the lap belt which loads the abdomen. The order of magnitude of the abdominal deflection rate was reported by Uriot to be approximately 4 m/s. In addition, the use of active restraint devices such as pretensioners in recent cars lead to the need for the investigation of Out-Of-Position injuries. OOP is defined by an initial position of the lap belt on the abdomen instead of the pelvis resulting in a direct loading of the abdomen during pretensioning and the crash. In that case, the penetration speed of the belt into the abdomen was reported by Trosseille to be approximately 8 to 12 m/s. The aim of this study was to characterize the response of the human abdomen in submarining and OOP.

Developing lightweight, stiff and crash-resistant vehicle body structures requires a balance between part geometry and material properties. High strength materials suitable for crash resistance impose geometry limitations on depth of draw, radii and wall angles that reduce geometric efficiency. The introduction of 3rd generation Advanced High Strength Steels (AHSS) can potentially change the relationship between strength and geometry and enable simultaneous improvements in both. This paper will demonstrate applicability of 3rd generation AHSS with higher strength and ductility to replace the 780 MPa Dual Phase steel in a sill reinforcement on the current Jeep Cherokee. The focus will be on formability, beginning with virtual simulation and continuing through a demonstration run on the current production stamping tools and press.

Crankshafts of motorcycles require high strength, high reliability and low manufacturing cost. Recently, a reduction of Pb content in the free-cutting steel, which is harmful substance, is required. In order to satisfy such requirements, we started the development of Pb-free free-cutting steel which simultaneously enabled the omission of the normalizing process. For the omission of normalizing process, we adjusted the content of Carbon, Manganese and Nitrogen of the steel. This developed steel can obtain adequate hardness and fine microstructure by air-cooling after forging. Pb-free free-cutting steel was developed based on Calcium-sulfur free-cutting steel. Pb free-cutting steel is excellent in cutting chips frangibility in lathe process. We thought that it was necessary that cutting chips frangibility of developed steel was equal to Pb free-cutting steel. It was found that cutting chips frangibility depend on a non-metallic inclusion's composition, shape and dispersion.

This paper will provide an overview of the work progress of the advanced offset frontal crash protection group of IHRA. It resumes, including tables, the strategy of the group to cope with the assigned task. This is the commitment to achieve an harmonized frontal crash protection procedure taking into account the different world wide views in this field.

This paper describes the risk of injury to the rider in a crash using a statistical model based on real-world accident data. We analyzed the road traffic accidents data in Los Angeles and Hanover. Logistic regression modeling technique was used to clarify the relationship among probabilities of minor, serious, fatal injury risk to the rider, and the influence of risk factors in accidents involving opposing vehicle contact point, motorcycle contact point, opposing vehicle speed, motorcycle speed, relative heading angle of impact, and helmet use. The odds ratio, which was adjusted for risk factors simultaneously, was estimated by using the developed technique, and was compared with the effects of risk factors individually. The results showed that there was a statistically significant relationship between minor and serious injuries and opposing vehicle speed, motorcycle speed and opposing vehicle contact point.

Previous applications of 980 XK steels in the automotive industry have been limited. However, to meet increased structural requirements of MVSS-301, AMC has incorporated 980 XK steel in the 1977 Gremlin and Hornet underbody rear sill subassemblies. This paper emphasizes how formability and spot weldability characteristics were optimized in order to meet the vehicular crashworthiness required in this structural application. Traditional mild steel design, forming, and spot welding procedures were successfully modified to utilize 980 XK. These modifications are practical and have been successfully incorporated in production operations.

Today’s automotive world has moved towards an age where safety of a vehicle is given the topmost priority. Many stringent crash norms and testing methodology has been defined in order to evaluate the safety of a vehicle prior to its launch in a particular market. If the vehicle fails to meet any of these criteria then it is debarred from that particular market. With such stringent norms and regulations in place it becomes quite important on the engineer’s part to define the structural requirements and protect the space to meet the same. If the concept level platform definition is done properly it becomes very easy to achieve the crash targets with less cost and weight impact.